dma: Automatically enable page touching on Caspian #5
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… avoid early OOMs This is the improved workaround to avoid early OOMs within cgroup v1 by throttling the memory reclaim given dirty/writeback pages under the GFP_NOFS allocations. Increment sleeping time exponentialy until a limit after half the number of maximum retries when writeback+dirty pages goes beyond a certain threshold before next retry occurs. This solution can not only help to prevent early OOMs on some extreme workload but also avoid unnecessary throttling on general cases. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207273 Suggested-by: Michal Hocko <[email protected]> Signed-off-by: Shaoying Xu <[email protected]>
(/sys/devices/system/memory/probe) can accept starting physical address of an entire memory block to be hot added into the kernel. This is in addition to the existing ACPI based interface. This just enables it with the required config CONFIG_ARCH_MEMORY_PROBE. Signed-off-by: Anshuman Khandual <[email protected]>
Issue: Offlining non-boot memory on arm64 via /sys/devices/system/memory/<mem_id>/state doesnt eliminate the struct page memory associated with the offlined memory. As memory is offlined, total and free memory reduce but the memory associated with struct page isnt given back and is reported as 'used' memory instead. This is because offlining via the sysfs 'state' probe doesnt remove the memmap associated with the memory to be offlined. Fix: Expose a sysfs probe that also removes memmap associated with the memory block after offlining it. Probe exposed accepts the physical address of a memory block to be removed. Signed-off-by: Rohit Wali <[email protected]>
Since commit e1c158e ("mm/memory_hotplug: remove nid parameter from remove_memory() and friends"), offline_and_remove_memory() no longer takes a node id arguments. Adapt. Signed-off-by: Frank van der Linden <[email protected]>
If it is possible to use MHP_MEMMAP_ON_MEMORY from the probe interface, which should normally be the case, do so. Signed-off-by: Frank van der Linden <[email protected]>
Add an interface to report offlined pages as free to the hypervisor. Define a new entry point for page reporting drivers, report_offline. If a driver sets it, it will be called after a range of memory has been offlined. This is done separately, and not with a memory notifier, since with memmap_on_memory, there are pages that are only freed outside of offline_pages, where the notifiers are called. Since this will be called asynchronously (e.g. not from the page reporting work queues), protect it with the page reporting mutex so that a driver can't be unloaded while calling the entry point. Signed-off-by: Frank van der Linden <[email protected]>
When reporting offlined pages through free page reporting, and memmap_on_memory is active, we don't want to touch the page structures anymore, since that will lead to a reference to the range we just offlined, as the page structures themselves reside in the range. So, we can't use sg_phys to set the dma address. Instead, if sg_page is set to NULL, assume that sg_dma_address is set already, and use it. Signed-off-by: Frank van der Linden <[email protected]>
A hack to report offlined memory ranges through virtio-balloon. Do this by registering a memory notifier callback for offlining, and then calling the normal free page reporting entry point to report the range that was just offlined. This is only active if the virtio_balloon.report_offline module parameter is set. Signed-off-by: Frank van der Linden <[email protected]>
Allows enabling page touching via a kernel command line parameter. When enabled, devices which don't have an IOMMU assigned to them will be assigned the page touching DMA map ops which ensures that any memory mapped for DMA by that devices will be accessed by the CPU to make it resident. Signed-off-by: James Gowans <[email protected]> Cc-Team: kaos-brimstone <[email protected]> Cc-Team: ec2-memo <[email protected]>
To force a page into residence, a read operation is performed on behalf of devices without an IOMMU. This functionality is required to facilitate memory overcommitted hosts. Commit 25d4ce2 ("Introduce page touching DMA ops binding") initially introduced this logic by invoking a '__raw_readl' function. This function can however read past the bounds of memory mapped for DMA. Instead, it is replaced with '__raw_readb'. This limits the length of memory read to a byte, and prevents reading past the range of mapped memory. Fixes: 25d4ce2 ("Introduce page touching DMA ops binding") Signed-off-by: Tighe Barris <[email protected]> Cc-Team: kaos-brimstone <[email protected]> Cc-Team: ec2-memo <[email protected]>
There's currently an issue with Xen and KASLR causing hibernation to break (and possibly kexec/kdump too). Until we have got to the bottom of this and fixed the root cause, let's disable KASLR at runtime when running on Xen instances so we can enable it for Nitro. This also adds a boot message to match ARM and help detect whether this test worked as expected. Signed-off-by: Benjamin Herrenschmidt <[email protected]>
Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
This provides a central place to maintain out-of-tree drivers. Renamed from VENDOR_AMAZON because the name was no longer appropriate. Signed-off-by: Munehisa Kamata <[email protected]> Reviewed-by: Cristian Gafton <[email protected]> Reviewed-by: Guru Anbalagane <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Reviewed-by: Anchal Agarwal <[email protected]> Signed-off-by: Vallish Vaidyeshwara <[email protected]>
Source: https://github.com/amzn/amzn-drivers/ Change Log: ## r2.8.1 release notes **New Features** * Add extended metrics mechanism support * Add conntrack customer metric to ethtool **Bug Fixes** * Fix compilation issues on SLES 15 SP4 * Fix compilation errors in RHEL 8.7, 9.0 * Configure TX rings mem policy in reset flow **Minor Changes** * Add napi_build_skb support * Add napi_consume_skb * Align ena_alloc_map_page signature * Move from strlcpy with unused retval to strscpy * Add status check for strscpy calls * Backport napi_alloc_skb usage
Source: https://github.com/amzn/amzn-drivers/ Change Log: ## r2.1.1 release notes * Fix dmabuf backport for some kernels
Squash the following 2 patches into 1 as they accomplish the same goal - setting which algorithims are availble for fips use in 6.1. not-for-upstream: testmgr config changes to enable FIPS boot The Federal Information Processing Standard (FIPS) Publication 140-2, is a computer security standard, developed by a U.S. Government and industry working group to validate the quality of cryptographic modules. Enabling FIPS mode involves the following steps: a. prelinking needs to be disabled. PRELINKING=no in /etc/sysconfig/prelink b. Install dracut-fips package # yum install dracut-fips. Installing dracut-fipes enables module signing by default and also enables scripts that do FIPS integrity verification, regardless of whether FIPS mode is on. If FIPS mode is on, and verification failure is detected, then syste will panic. c. Recreate initramfs # dracut -v -f d. Modify kernel command line to include the following option fips=1. For gaub2 based system add fips=1 to the end of the CMDLINE in /etc/default/grub and then run the following command # grub2-mkconfig -o /boot/grub2/grub.cfg e. Reboot the system. In FIPS mode, some self tests are run by dracut-fips package which is otherwise not the case for kernel not running in FIPS mode. The changes in the tests mentioned in this CR is only relevant for kernel running in FIPS mode. In this changeset, we enable/disable cryptographic algorithms in FIPS mode to make sure that we enable the tests that are supportedand disable the tests that are not supported in our kernel. Among the tests that are not supported are the SHA3 family of tests and their hmac versions. Also gcm(aesni) is disabled as the support is currently missing in the kernel. Also we should remember that, this change is not an effort to make the kernel FIPS compliant. FIPS compliance needs to be done by certified authority. This change is about adding support for FIPS mode. Running official FIPS compliance may necessiate support for additional cryptographic algorithms or remove fips_enabed flag in the tests for few algorithms as the need may arise. FIPS mode for a test is disabled by removing fips_enabled = 1 from the test description in testmgr.c. Adding support is more involved. The test needs to be implemented and pointed to in the structure used to describe the test. In FIPS mode, only the tests that are tagged with fips_enabled=1 are run and rest of the tests are ignored. So if you are not sure about an algorithm which needs to be enabled in FIPS mode, it needs to be disabled in testmgr.c. NU: because FIPS enablement is distro specific. Signed-off-by: Alakesh Haloi <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Reviewed-by: Anchal Agarwal <[email protected]> Reviewed-by: Cristian Gafton <[email protected]> Reviewed-by: Frederick Lefebvre <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Vallish Vaidyeshwara <[email protected]> enable rfc4106(gcm(aes)) for fips This alogrithim works with no additional changes required and has been requested by a customer, so enable it
To differentiate between Xen suspend, PM suspend and PM hibernation, keep track of the on-going suspend mode by mainly using a new PM notifier. Since Xen suspend doesn't have corresponding PM event, its main logic is modfied to acquire pm_mutex and set the current mode. Note that we may see deadlock if PM suspend/hibernation is interrupted by Xen suspend. PM suspend/hibernation depends on xenwatch thread to process xenbus state transactions, but the thread will sleep to wait pm_mutex which is already held by PM suspend/hibernation context in the scenario. Though, acquirng pm_mutex is still right thing to do, and we would need to modify Xen shutdown code to avoid the issue. This will be fixed by a separate patch. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Sebastian Biemueller <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> [6.1: Handle sleep flags for unlock_system_sleep()] Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Introduce simple functions which help to know the on-going suspend mode so that other Xen-related code can behave differently according to the current suspend mode. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Alakesh Haloi <[email protected]> Reviewed-by: Sebastian Biemueller <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Since commit b3e96c0 ("xen: use freeze/restore/thaw PM events for suspend/resume/chkpt"), xenbus uses PMSG_FREEZE, PMSG_THAW and PMSG_RESTORE events for Xen suspend. However, they're actually assigned to xenbus_dev_suspend(), xenbus_dev_cancel() and xenbus_dev_resume() respectively, and only suspend and resume callbacks are supported at driver level. To support PM suspend and PM hibernation, modify the bus level PM callbacks to invoke not only device driver's suspend/resume but also freeze/thaw/restore. Note that we'll use freeze/restore callbacks even for PM suspend whereas suspend/resume callbacks are normally used in the case, becausae the existing xenbus device drivers already have suspend/resume callbacks specifically designed for Xen suspend. So we can allow the device drivers to keep the existing callbacks wihtout modification. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Introduce a small function which re-uses shared page's PA allocated
during guest initialization time in reserve_shared_info() and not
allocate new page during resume flow.
It also does the mapping of shared_info_page by calling
xen_hvm_init_shared_info() to use the function.
Backport Notes:
We don't need this commit 8d5ce0dad4ab2a4c8c8a3c36f6fb8c46b695b053 ("x86/xen:
decouple shared_info mapping from xen_hvm_init_shared_info()") here since
xen_hvm_init_shared_info changed in 4.14 kernel just to do the mapping and
allocation of shared page is done in a separate function.
We don't need to decouple this kernel API anymore
Signed-off-by: Anchal Agarwal <[email protected]>
Reviewed-by: Sebastian Biemueller <[email protected]>
Reviewed-by: Munehisa Kamata <[email protected]>
Reviewed-by: Eduardo Valentin <[email protected]>
Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Add Xen PVHVM specific system core callbacks for PM suspend and hibernation support. The callbacks suspend and resume Xen primitives, like shared_info, pvclock and grant table. Note that Xen suspend can handle them in a different manner, but system core callbacks are called from the context. So if the callbacks are called from Xen suspend context, return immediately. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Add freeze and restore callbacks for PM suspend and hibernation support. The freeze handler stops a block-layer queue and disconnect the frontend from the backend while freeing ring_info and associated resources. The restore handler re-allocates ring_info and re-connect to the backedend, so the rest of the kernel can continue to use the block device transparently.Also, the handlers are used for both PM suspend and hibernation so that we can keep the existing suspend/resume callbacks for Xen suspend without modification. If a backend doesn't have commit 12ea729 ("xen/blkback: unmap all persistent grants when frontend gets disconnected"), the frontend may see massive amount of grant table warning when freeing resources. [ 36.852659] deferring g.e. 0xf9 (pfn 0xffffffffffffffff) [ 36.855089] xen:grant_table: WARNING: g.e. 0x112 still in use! In this case, persistent grants would need to be disabled. Ensure no reqs/rsps in rings before disconnecting. When disconnecting the frontend from the backend in blkfront_freeze(), there still may be unconsumed requests or responses in the rings, especially when the backend is backed by network-based device. If the frontend gets disconnected with such reqs/rsps remaining there, it can cause grant warnings and/or losing reqs/rsps by freeing pages afterward. This can lead resumed kernel into unrecoverable state like unexpected freeing of grant page and/or hung task due to the lost reqs or rsps. Therefore we have to ensure that there is no unconsumed requests or responses before disconnecting. Actually, the frontend just needs to wait for some amount of time so that the backend can process the requests, put responses and notify the frontend back. Timeout used here is based on some heuristic. If we somehow hit the timeout, it would mean something serious happens in the backend, the frontend will just return an error to PM core and PM suspend/hibernation will be aborted. This may be something should be fixed by the backend side, but a frontend side fix is probably still worth doing to work with broader backends. Backport Note: Unlike 4.9 kernel, blk-mq is default for 4.14 kernel and request-based mode cod eis not included in this frontend driver. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Add freeze and restore callbacks for PM suspend and hibernation support. The freeze handler simply disconnects the frotnend from the backend and frees resources associated with queues after disabling the net_device from the system. The restore handler just changes the frontend state and let the xenbus handler to re-allocate the resources and re-connect to the backend. This can be performed transparently to the rest of the system. The handlers are used for both PM suspend and hibernation so that we can keep the existing suspend/resume callbacks for Xen suspend without modification. Freezing netfront devices is normally expected to finish within a few hundred milliseconds, but it can rarely take more than 5 seconds and hit the hard coded timeout, it would depend on backend state which may be congested and/or have complex configuration. While it's rare case, longer default timeout seems a bit more reasonable here to avoid hitting the timeout. Also, make it configurable via module parameter so that we can cover broader setups than what we know currently. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Currently, steal time accounting code in scheduler expects steal clock callback to provide monotonically increasing value. If the accounting code receives a smaller value than previous one, it uses a negative value to calculate steal time and results in incorrectly updated idle and steal time accounting. This breaks userspace tools which read /proc/stat. top - 08:05:35 up 2:12, 3 users, load average: 0.00, 0.07, 0.23 Tasks: 80 total, 1 running, 79 sleeping, 0 stopped, 0 zombie Cpu(s): 0.0%us, 0.0%sy, 0.0%ni,30100.0%id, 0.0%wa, 0.0%hi, 0.0%si,-1253874204672.0%st This can actually happen when a Xen PVHVM guest gets restored from hibernation, because such a restored guest is just a fresh domain from Xen perspective and the time information in runstate info starts over from scratch. This patch introduces xen_save_steal_clock() which saves current values in runstate info into per-cpu variables. Its couterpart, xen_restore_steal_clock(), sets offset if it found the current values in runstate info are smaller than previous ones. xen_steal_clock() is also modified to use the offset to ensure that scheduler only sees monotonically increasing number. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Save steal clock values of all present CPUs in the system core ops suspend callbacks. Also, restore a boot CPU's steal clock in the system core resume callback. For non-boot CPUs, restore after they're brought up, because runstate info for non-boot CPUs are not active until then. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Add a simple helper function to "shutdown" active PIRQs, which actually closes event channels but keeps related IRQ structures intact. PM suspend/hibernation code will rely on this. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
Close event channels allocated for devices which are backed by PIRQ and still active when suspending the system core. Normally, the devices are emulated legacy devices, e.g. PS/2 keyboard, floppy controller and etc. Without this, in PM hibernation, information about the event channel remains in hibernation image, but there is no guarantee that the same event channel numbers are assigned to the devices when restoring the system. This may cause conflict like the following and prevent some devices from being restored correctly. [ 102.330821] ------------[ cut here ]------------ [ 102.333264] WARNING: CPU: 0 PID: 2324 at drivers/xen/events/events_base.c:878 bind_evtchn_to_irq+0x88/0xf0 ... [ 102.348057] Call Trace: [ 102.348057] [<ffffffff813001df>] dump_stack+0x63/0x84 [ 102.348057] [<ffffffff81071811>] __warn+0xd1/0xf0 [ 102.348057] [<ffffffff810718fd>] warn_slowpath_null+0x1d/0x20 [ 102.348057] [<ffffffff8139a1f8>] bind_evtchn_to_irq+0x88/0xf0 [ 102.348057] [<ffffffffa00cd420>] ? blkif_copy_from_grant+0xb0/0xb0 [xen_blkfront] [ 102.348057] [<ffffffff8139a307>] bind_evtchn_to_irqhandler+0x27/0x80 [ 102.348057] [<ffffffffa00cc785>] talk_to_blkback+0x425/0xcd0 [xen_blkfront] [ 102.348057] [<ffffffff811e0c8a>] ? __kmalloc+0x1ea/0x200 [ 102.348057] [<ffffffffa00ce84d>] blkfront_restore+0x2d/0x60 [xen_blkfront] [ 102.348057] [<ffffffff813a0078>] xenbus_dev_restore+0x58/0x100 [ 102.348057] [<ffffffff813a1ff0>] ? xenbus_frontend_delayed_resume+0x20/0x20 [ 102.348057] [<ffffffff813a200e>] xenbus_dev_cond_restore+0x1e/0x30 [ 102.348057] [<ffffffff813f797e>] dpm_run_callback+0x4e/0x130 [ 102.348057] [<ffffffff813f7f17>] device_resume+0xe7/0x210 [ 102.348057] [<ffffffff813f7810>] ? pm_dev_dbg+0x80/0x80 [ 102.348057] [<ffffffff813f9374>] dpm_resume+0x114/0x2f0 [ 102.348057] [<ffffffff810c00cf>] hibernation_snapshot+0x15f/0x380 [ 102.348057] [<ffffffff810c0ac3>] hibernate+0x183/0x290 [ 102.348057] [<ffffffff810be1af>] state_store+0xcf/0xe0 [ 102.348057] [<ffffffff813020bf>] kobj_attr_store+0xf/0x20 [ 102.348057] [<ffffffff8127c88a>] sysfs_kf_write+0x3a/0x50 [ 102.348057] [<ffffffff8127c3bb>] kernfs_fop_write+0x10b/0x190 [ 102.348057] [<ffffffff81200008>] __vfs_write+0x28/0x120 [ 102.348057] [<ffffffff81200c19>] ? rw_verify_area+0x49/0xb0 [ 102.348057] [<ffffffff81200e62>] vfs_write+0xb2/0x1b0 [ 102.348057] [<ffffffff81202196>] SyS_write+0x46/0xa0 [ 102.348057] [<ffffffff81520cf7>] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 102.423005] ---[ end trace b8d6718e22e2b107 ]--- [ 102.425031] genirq: Flags mismatch irq 6. 00000000 (blkif) vs. 00000000 (floppy) Note that we don't explicitly re-allocate event channels for such devices in the resume callback. Re-allocation will occur when PM core re-enable IRQs for the devices at later point. Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
The SNAPSHOT_SET_SWAP_AREA is supposed to be used to set the hibernation offset on a running kernel to enable hibernating to a swap file. However, it doesn't actually update the swsusp_resume_block variable. As a result, the hibernation fails at the last step (after all the data is written out) in the validation of the swap signature in mark_swapfiles(). Before this patch, the command line processing was the only place where swsusp_resume_block was set. Signed-off-by: Aleksei Besogonov <[email protected]> Signed-off-by: Munehisa Kamata <[email protected]> Signed-off-by: Anchal Agarwal <[email protected]> Reviewed-by: Munehisa Kamata <[email protected]> Reviewed-by: Eduardo Valentin <[email protected]> Signed-off-by: Samuel Mendoza-Jonas <[email protected]>
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Nov 18, 2025
commit 8410f70 upstream. Our test report a UAF: [ 2073.019181] ================================================================== [ 2073.019188] BUG: KASAN: use-after-free in __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019191] Write of size 8 at addr ffff8000ccf64128 by task rmmod/72584 [ 2073.019192] [ 2073.019196] CPU: 0 PID: 72584 Comm: rmmod Kdump: loaded Not tainted 4.19.90-yk #5 [ 2073.019198] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 2073.019200] Call trace: [ 2073.019203] dump_backtrace+0x0/0x310 [ 2073.019206] show_stack+0x28/0x38 [ 2073.019210] dump_stack+0xec/0x15c [ 2073.019216] print_address_description+0x68/0x2d0 [ 2073.019220] kasan_report+0x238/0x2f0 [ 2073.019224] __asan_store8+0x88/0xb0 [ 2073.019229] __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019233] bfq_put_async_queues+0xbc/0x208 [ 2073.019236] bfq_pd_offline+0x178/0x238 [ 2073.019240] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019244] bfq_exit_queue+0x128/0x178 [ 2073.019249] blk_mq_exit_sched+0x12c/0x160 [ 2073.019252] elevator_exit+0xc8/0xd0 [ 2073.019256] blk_exit_queue+0x50/0x88 [ 2073.019259] blk_cleanup_queue+0x228/0x3d8 [ 2073.019267] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019274] null_exit+0x90/0x114 [null_blk] [ 2073.019278] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019282] el0_svc_common+0xc8/0x320 [ 2073.019287] el0_svc_handler+0xf8/0x160 [ 2073.019290] el0_svc+0x10/0x218 [ 2073.019291] [ 2073.019294] Allocated by task 14163: [ 2073.019301] kasan_kmalloc+0xe0/0x190 [ 2073.019305] kmem_cache_alloc_node_trace+0x1cc/0x418 [ 2073.019308] bfq_pd_alloc+0x54/0x118 [ 2073.019313] blkcg_activate_policy+0x250/0x460 [ 2073.019317] bfq_create_group_hierarchy+0x38/0x110 [ 2073.019321] bfq_init_queue+0x6d0/0x948 [ 2073.019325] blk_mq_init_sched+0x1d8/0x390 [ 2073.019330] elevator_switch_mq+0x88/0x170 [ 2073.019334] elevator_switch+0x140/0x270 [ 2073.019338] elv_iosched_store+0x1a4/0x2a0 [ 2073.019342] queue_attr_store+0x90/0xe0 [ 2073.019348] sysfs_kf_write+0xa8/0xe8 [ 2073.019351] kernfs_fop_write+0x1f8/0x378 [ 2073.019359] __vfs_write+0xe0/0x360 [ 2073.019363] vfs_write+0xf0/0x270 [ 2073.019367] ksys_write+0xdc/0x1b8 [ 2073.019371] __arm64_sys_write+0x50/0x60 [ 2073.019375] el0_svc_common+0xc8/0x320 [ 2073.019380] el0_svc_handler+0xf8/0x160 [ 2073.019383] el0_svc+0x10/0x218 [ 2073.019385] [ 2073.019387] Freed by task 72584: [ 2073.019391] __kasan_slab_free+0x120/0x228 [ 2073.019394] kasan_slab_free+0x10/0x18 [ 2073.019397] kfree+0x94/0x368 [ 2073.019400] bfqg_put+0x64/0xb0 [ 2073.019404] bfqg_and_blkg_put+0x90/0xb0 [ 2073.019408] bfq_put_queue+0x220/0x228 [ 2073.019413] __bfq_put_async_bfqq+0x98/0x168 [ 2073.019416] bfq_put_async_queues+0xbc/0x208 [ 2073.019420] bfq_pd_offline+0x178/0x238 [ 2073.019424] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019429] bfq_exit_queue+0x128/0x178 [ 2073.019433] blk_mq_exit_sched+0x12c/0x160 [ 2073.019437] elevator_exit+0xc8/0xd0 [ 2073.019440] blk_exit_queue+0x50/0x88 [ 2073.019443] blk_cleanup_queue+0x228/0x3d8 [ 2073.019451] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019459] null_exit+0x90/0x114 [null_blk] [ 2073.019462] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019467] el0_svc_common+0xc8/0x320 [ 2073.019471] el0_svc_handler+0xf8/0x160 [ 2073.019474] el0_svc+0x10/0x218 [ 2073.019475] [ 2073.019479] The buggy address belongs to the object at ffff8000ccf63f00 which belongs to the cache kmalloc-1024 of size 1024 [ 2073.019484] The buggy address is located 552 bytes inside of 1024-byte region [ffff8000ccf63f00, ffff8000ccf64300) [ 2073.019486] The buggy address belongs to the page: [ 2073.019492] page:ffff7e000333d800 count:1 mapcount:0 mapping:ffff8000c0003a00 index:0x0 compound_mapcount: 0 [ 2073.020123] flags: 0x7ffff0000008100(slab|head) [ 2073.020403] raw: 07ffff0000008100 ffff7e0003334c08 ffff7e00001f5a08 ffff8000c0003a00 [ 2073.020409] raw: 0000000000000000 00000000001c001c 00000001ffffffff 0000000000000000 [ 2073.020411] page dumped because: kasan: bad access detected [ 2073.020412] [ 2073.020414] Memory state around the buggy address: [ 2073.020420] ffff8000ccf64000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020424] ffff8000ccf64080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020428] >ffff8000ccf64100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020430] ^ [ 2073.020434] ffff8000ccf64180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020438] ffff8000ccf64200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020439] ================================================================== The same problem exist in mainline as well. This is because oom_bfqq is moved to a non-root group, thus root_group is freed earlier. Thus fix the problem by don't move oom_bfqq. Signed-off-by: Yu Kuai <[email protected]> Reviewed-by: Jan Kara <[email protected]> Acked-by: Paolo Valente <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Andrew Paniakin <[email protected]>
surajjs95
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Nov 20, 2025
Evaluate _DSM Function #5, the "PCI Boot Configuration" function. If the result is 0, the OS should preserve any resource assignments made by the firmware. Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Benjamin Herrenschmidt <[email protected]> [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas <[email protected]> (cherry picked from commit a78cf96)
surajjs95
pushed a commit
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Nov 20, 2025
commit 8410f70 upstream. Our test report a UAF: [ 2073.019181] ================================================================== [ 2073.019188] BUG: KASAN: use-after-free in __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019191] Write of size 8 at addr ffff8000ccf64128 by task rmmod/72584 [ 2073.019192] [ 2073.019196] CPU: 0 PID: 72584 Comm: rmmod Kdump: loaded Not tainted 4.19.90-yk #5 [ 2073.019198] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 2073.019200] Call trace: [ 2073.019203] dump_backtrace+0x0/0x310 [ 2073.019206] show_stack+0x28/0x38 [ 2073.019210] dump_stack+0xec/0x15c [ 2073.019216] print_address_description+0x68/0x2d0 [ 2073.019220] kasan_report+0x238/0x2f0 [ 2073.019224] __asan_store8+0x88/0xb0 [ 2073.019229] __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019233] bfq_put_async_queues+0xbc/0x208 [ 2073.019236] bfq_pd_offline+0x178/0x238 [ 2073.019240] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019244] bfq_exit_queue+0x128/0x178 [ 2073.019249] blk_mq_exit_sched+0x12c/0x160 [ 2073.019252] elevator_exit+0xc8/0xd0 [ 2073.019256] blk_exit_queue+0x50/0x88 [ 2073.019259] blk_cleanup_queue+0x228/0x3d8 [ 2073.019267] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019274] null_exit+0x90/0x114 [null_blk] [ 2073.019278] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019282] el0_svc_common+0xc8/0x320 [ 2073.019287] el0_svc_handler+0xf8/0x160 [ 2073.019290] el0_svc+0x10/0x218 [ 2073.019291] [ 2073.019294] Allocated by task 14163: [ 2073.019301] kasan_kmalloc+0xe0/0x190 [ 2073.019305] kmem_cache_alloc_node_trace+0x1cc/0x418 [ 2073.019308] bfq_pd_alloc+0x54/0x118 [ 2073.019313] blkcg_activate_policy+0x250/0x460 [ 2073.019317] bfq_create_group_hierarchy+0x38/0x110 [ 2073.019321] bfq_init_queue+0x6d0/0x948 [ 2073.019325] blk_mq_init_sched+0x1d8/0x390 [ 2073.019330] elevator_switch_mq+0x88/0x170 [ 2073.019334] elevator_switch+0x140/0x270 [ 2073.019338] elv_iosched_store+0x1a4/0x2a0 [ 2073.019342] queue_attr_store+0x90/0xe0 [ 2073.019348] sysfs_kf_write+0xa8/0xe8 [ 2073.019351] kernfs_fop_write+0x1f8/0x378 [ 2073.019359] __vfs_write+0xe0/0x360 [ 2073.019363] vfs_write+0xf0/0x270 [ 2073.019367] ksys_write+0xdc/0x1b8 [ 2073.019371] __arm64_sys_write+0x50/0x60 [ 2073.019375] el0_svc_common+0xc8/0x320 [ 2073.019380] el0_svc_handler+0xf8/0x160 [ 2073.019383] el0_svc+0x10/0x218 [ 2073.019385] [ 2073.019387] Freed by task 72584: [ 2073.019391] __kasan_slab_free+0x120/0x228 [ 2073.019394] kasan_slab_free+0x10/0x18 [ 2073.019397] kfree+0x94/0x368 [ 2073.019400] bfqg_put+0x64/0xb0 [ 2073.019404] bfqg_and_blkg_put+0x90/0xb0 [ 2073.019408] bfq_put_queue+0x220/0x228 [ 2073.019413] __bfq_put_async_bfqq+0x98/0x168 [ 2073.019416] bfq_put_async_queues+0xbc/0x208 [ 2073.019420] bfq_pd_offline+0x178/0x238 [ 2073.019424] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019429] bfq_exit_queue+0x128/0x178 [ 2073.019433] blk_mq_exit_sched+0x12c/0x160 [ 2073.019437] elevator_exit+0xc8/0xd0 [ 2073.019440] blk_exit_queue+0x50/0x88 [ 2073.019443] blk_cleanup_queue+0x228/0x3d8 [ 2073.019451] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019459] null_exit+0x90/0x114 [null_blk] [ 2073.019462] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019467] el0_svc_common+0xc8/0x320 [ 2073.019471] el0_svc_handler+0xf8/0x160 [ 2073.019474] el0_svc+0x10/0x218 [ 2073.019475] [ 2073.019479] The buggy address belongs to the object at ffff8000ccf63f00 which belongs to the cache kmalloc-1024 of size 1024 [ 2073.019484] The buggy address is located 552 bytes inside of 1024-byte region [ffff8000ccf63f00, ffff8000ccf64300) [ 2073.019486] The buggy address belongs to the page: [ 2073.019492] page:ffff7e000333d800 count:1 mapcount:0 mapping:ffff8000c0003a00 index:0x0 compound_mapcount: 0 [ 2073.020123] flags: 0x7ffff0000008100(slab|head) [ 2073.020403] raw: 07ffff0000008100 ffff7e0003334c08 ffff7e00001f5a08 ffff8000c0003a00 [ 2073.020409] raw: 0000000000000000 00000000001c001c 00000001ffffffff 0000000000000000 [ 2073.020411] page dumped because: kasan: bad access detected [ 2073.020412] [ 2073.020414] Memory state around the buggy address: [ 2073.020420] ffff8000ccf64000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020424] ffff8000ccf64080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020428] >ffff8000ccf64100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020430] ^ [ 2073.020434] ffff8000ccf64180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020438] ffff8000ccf64200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020439] ================================================================== The same problem exist in mainline as well. This is because oom_bfqq is moved to a non-root group, thus root_group is freed earlier. Thus fix the problem by don't move oom_bfqq. Signed-off-by: Yu Kuai <[email protected]> Reviewed-by: Jan Kara <[email protected]> Acked-by: Paolo Valente <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Andrew Paniakin <[email protected]>
nathan-zcgao
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that referenced
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Nov 22, 2025
Evaluate _DSM Function #5, the "PCI Boot Configuration" function. If the result is 0, the OS should preserve any resource assignments made by the firmware. Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Benjamin Herrenschmidt <[email protected]> [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas <[email protected]> (cherry picked from commit a78cf96)
nathan-zcgao
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that referenced
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Nov 22, 2025
commit 8410f70 upstream. Our test report a UAF: [ 2073.019181] ================================================================== [ 2073.019188] BUG: KASAN: use-after-free in __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019191] Write of size 8 at addr ffff8000ccf64128 by task rmmod/72584 [ 2073.019192] [ 2073.019196] CPU: 0 PID: 72584 Comm: rmmod Kdump: loaded Not tainted 4.19.90-yk #5 [ 2073.019198] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 2073.019200] Call trace: [ 2073.019203] dump_backtrace+0x0/0x310 [ 2073.019206] show_stack+0x28/0x38 [ 2073.019210] dump_stack+0xec/0x15c [ 2073.019216] print_address_description+0x68/0x2d0 [ 2073.019220] kasan_report+0x238/0x2f0 [ 2073.019224] __asan_store8+0x88/0xb0 [ 2073.019229] __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019233] bfq_put_async_queues+0xbc/0x208 [ 2073.019236] bfq_pd_offline+0x178/0x238 [ 2073.019240] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019244] bfq_exit_queue+0x128/0x178 [ 2073.019249] blk_mq_exit_sched+0x12c/0x160 [ 2073.019252] elevator_exit+0xc8/0xd0 [ 2073.019256] blk_exit_queue+0x50/0x88 [ 2073.019259] blk_cleanup_queue+0x228/0x3d8 [ 2073.019267] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019274] null_exit+0x90/0x114 [null_blk] [ 2073.019278] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019282] el0_svc_common+0xc8/0x320 [ 2073.019287] el0_svc_handler+0xf8/0x160 [ 2073.019290] el0_svc+0x10/0x218 [ 2073.019291] [ 2073.019294] Allocated by task 14163: [ 2073.019301] kasan_kmalloc+0xe0/0x190 [ 2073.019305] kmem_cache_alloc_node_trace+0x1cc/0x418 [ 2073.019308] bfq_pd_alloc+0x54/0x118 [ 2073.019313] blkcg_activate_policy+0x250/0x460 [ 2073.019317] bfq_create_group_hierarchy+0x38/0x110 [ 2073.019321] bfq_init_queue+0x6d0/0x948 [ 2073.019325] blk_mq_init_sched+0x1d8/0x390 [ 2073.019330] elevator_switch_mq+0x88/0x170 [ 2073.019334] elevator_switch+0x140/0x270 [ 2073.019338] elv_iosched_store+0x1a4/0x2a0 [ 2073.019342] queue_attr_store+0x90/0xe0 [ 2073.019348] sysfs_kf_write+0xa8/0xe8 [ 2073.019351] kernfs_fop_write+0x1f8/0x378 [ 2073.019359] __vfs_write+0xe0/0x360 [ 2073.019363] vfs_write+0xf0/0x270 [ 2073.019367] ksys_write+0xdc/0x1b8 [ 2073.019371] __arm64_sys_write+0x50/0x60 [ 2073.019375] el0_svc_common+0xc8/0x320 [ 2073.019380] el0_svc_handler+0xf8/0x160 [ 2073.019383] el0_svc+0x10/0x218 [ 2073.019385] [ 2073.019387] Freed by task 72584: [ 2073.019391] __kasan_slab_free+0x120/0x228 [ 2073.019394] kasan_slab_free+0x10/0x18 [ 2073.019397] kfree+0x94/0x368 [ 2073.019400] bfqg_put+0x64/0xb0 [ 2073.019404] bfqg_and_blkg_put+0x90/0xb0 [ 2073.019408] bfq_put_queue+0x220/0x228 [ 2073.019413] __bfq_put_async_bfqq+0x98/0x168 [ 2073.019416] bfq_put_async_queues+0xbc/0x208 [ 2073.019420] bfq_pd_offline+0x178/0x238 [ 2073.019424] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019429] bfq_exit_queue+0x128/0x178 [ 2073.019433] blk_mq_exit_sched+0x12c/0x160 [ 2073.019437] elevator_exit+0xc8/0xd0 [ 2073.019440] blk_exit_queue+0x50/0x88 [ 2073.019443] blk_cleanup_queue+0x228/0x3d8 [ 2073.019451] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019459] null_exit+0x90/0x114 [null_blk] [ 2073.019462] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019467] el0_svc_common+0xc8/0x320 [ 2073.019471] el0_svc_handler+0xf8/0x160 [ 2073.019474] el0_svc+0x10/0x218 [ 2073.019475] [ 2073.019479] The buggy address belongs to the object at ffff8000ccf63f00 which belongs to the cache kmalloc-1024 of size 1024 [ 2073.019484] The buggy address is located 552 bytes inside of 1024-byte region [ffff8000ccf63f00, ffff8000ccf64300) [ 2073.019486] The buggy address belongs to the page: [ 2073.019492] page:ffff7e000333d800 count:1 mapcount:0 mapping:ffff8000c0003a00 index:0x0 compound_mapcount: 0 [ 2073.020123] flags: 0x7ffff0000008100(slab|head) [ 2073.020403] raw: 07ffff0000008100 ffff7e0003334c08 ffff7e00001f5a08 ffff8000c0003a00 [ 2073.020409] raw: 0000000000000000 00000000001c001c 00000001ffffffff 0000000000000000 [ 2073.020411] page dumped because: kasan: bad access detected [ 2073.020412] [ 2073.020414] Memory state around the buggy address: [ 2073.020420] ffff8000ccf64000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020424] ffff8000ccf64080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020428] >ffff8000ccf64100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020430] ^ [ 2073.020434] ffff8000ccf64180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020438] ffff8000ccf64200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020439] ================================================================== The same problem exist in mainline as well. This is because oom_bfqq is moved to a non-root group, thus root_group is freed earlier. Thus fix the problem by don't move oom_bfqq. Signed-off-by: Yu Kuai <[email protected]> Reviewed-by: Jan Kara <[email protected]> Acked-by: Paolo Valente <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Andrew Paniakin <[email protected]>
shaoyingxu
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Nov 24, 2025
[ Upstream commit 84bbe32 ] On completion of i915_vma_pin_ww(), a synchronous variant of dma_fence_work_commit() is called. When pinning a VMA to GGTT address space on a Cherry View family processor, or on a Broxton generation SoC with VTD enabled, i.e., when stop_machine() is then called from intel_ggtt_bind_vma(), that can potentially lead to lock inversion among reservation_ww and cpu_hotplug locks. [86.861179] ====================================================== [86.861193] WARNING: possible circular locking dependency detected [86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G U [86.861226] ------------------------------------------------------ [86.861238] i915_module_loa/1432 is trying to acquire lock: [86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50 [86.861290] but task is already holding lock: [86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.862233] which lock already depends on the new lock. [86.862251] the existing dependency chain (in reverse order) is: [86.862265] -> #5 (reservation_ww_class_mutex){+.+.}-{3:3}: [86.862292] dma_resv_lockdep+0x19a/0x390 [86.862315] do_one_initcall+0x60/0x3f0 [86.862334] kernel_init_freeable+0x3cd/0x680 [86.862353] kernel_init+0x1b/0x200 [86.862369] ret_from_fork+0x47/0x70 [86.862383] ret_from_fork_asm+0x1a/0x30 [86.862399] -> #4 (reservation_ww_class_acquire){+.+.}-{0:0}: [86.862425] dma_resv_lockdep+0x178/0x390 [86.862440] do_one_initcall+0x60/0x3f0 [86.862454] kernel_init_freeable+0x3cd/0x680 [86.862470] kernel_init+0x1b/0x200 [86.862482] ret_from_fork+0x47/0x70 [86.862495] ret_from_fork_asm+0x1a/0x30 [86.862509] -> #3 (&mm->mmap_lock){++++}-{3:3}: [86.862531] down_read_killable+0x46/0x1e0 [86.862546] lock_mm_and_find_vma+0xa2/0x280 [86.862561] do_user_addr_fault+0x266/0x8e0 [86.862578] exc_page_fault+0x8a/0x2f0 [86.862593] asm_exc_page_fault+0x27/0x30 [86.862607] filldir64+0xeb/0x180 [86.862620] kernfs_fop_readdir+0x118/0x480 [86.862635] iterate_dir+0xcf/0x2b0 [86.862648] __x64_sys_getdents64+0x84/0x140 [86.862661] x64_sys_call+0x1058/0x2660 [86.862675] do_syscall_64+0x91/0xe90 [86.862689] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.862703] -> #2 (&root->kernfs_rwsem){++++}-{3:3}: [86.862725] down_write+0x3e/0xf0 [86.862738] kernfs_add_one+0x30/0x3c0 [86.862751] kernfs_create_dir_ns+0x53/0xb0 [86.862765] internal_create_group+0x134/0x4c0 [86.862779] sysfs_create_group+0x13/0x20 [86.862792] topology_add_dev+0x1d/0x30 [86.862806] cpuhp_invoke_callback+0x4b5/0x850 [86.862822] cpuhp_issue_call+0xbf/0x1f0 [86.862836] __cpuhp_setup_state_cpuslocked+0x111/0x320 [86.862852] __cpuhp_setup_state+0xb0/0x220 [86.862866] topology_sysfs_init+0x30/0x50 [86.862879] do_one_initcall+0x60/0x3f0 [86.862893] kernel_init_freeable+0x3cd/0x680 [86.862908] kernel_init+0x1b/0x200 [86.862921] ret_from_fork+0x47/0x70 [86.862934] ret_from_fork_asm+0x1a/0x30 [86.862947] -> #1 (cpuhp_state_mutex){+.+.}-{3:3}: [86.862969] __mutex_lock+0xaa/0xed0 [86.862982] mutex_lock_nested+0x1b/0x30 [86.862995] __cpuhp_setup_state_cpuslocked+0x67/0x320 [86.863012] __cpuhp_setup_state+0xb0/0x220 [86.863026] page_alloc_init_cpuhp+0x2d/0x60 [86.863041] mm_core_init+0x22/0x2d0 [86.863054] start_kernel+0x576/0xbd0 [86.863068] x86_64_start_reservations+0x18/0x30 [86.863084] x86_64_start_kernel+0xbf/0x110 [86.863098] common_startup_64+0x13e/0x141 [86.863114] -> #0 (cpu_hotplug_lock){++++}-{0:0}: [86.863135] __lock_acquire+0x1635/0x2810 [86.863152] lock_acquire+0xc4/0x2f0 [86.863166] cpus_read_lock+0x41/0x100 [86.863180] stop_machine+0x1c/0x50 [86.863194] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.863987] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.864735] __vma_bind+0x55/0x70 [i915] [86.865510] fence_work+0x26/0xa0 [i915] [86.866248] fence_notify+0xa1/0x140 [i915] [86.866983] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.867719] i915_sw_fence_commit+0x39/0x60 [i915] [86.868453] i915_vma_pin_ww+0x462/0x1360 [i915] [86.869228] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.870001] initial_plane_vma+0x307/0x840 [i915] [86.870774] intel_initial_plane_config+0x33f/0x670 [i915] [86.871546] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.872330] i915_driver_probe+0x7fa/0xe80 [i915] [86.873057] i915_pci_probe+0xe6/0x220 [i915] [86.873782] local_pci_probe+0x47/0xb0 [86.873802] pci_device_probe+0xf3/0x260 [86.873817] really_probe+0xf1/0x3c0 [86.873833] __driver_probe_device+0x8c/0x180 [86.873848] driver_probe_device+0x24/0xd0 [86.873862] __driver_attach+0x10f/0x220 [86.873876] bus_for_each_dev+0x7f/0xe0 [86.873892] driver_attach+0x1e/0x30 [86.873904] bus_add_driver+0x151/0x290 [86.873917] driver_register+0x5e/0x130 [86.873931] __pci_register_driver+0x7d/0x90 [86.873945] i915_pci_register_driver+0x23/0x30 [i915] [86.874678] i915_init+0x37/0x120 [i915] [86.875347] do_one_initcall+0x60/0x3f0 [86.875369] do_init_module+0x97/0x2a0 [86.875385] load_module+0x2c54/0x2d80 [86.875398] init_module_from_file+0x96/0xe0 [86.875413] idempotent_init_module+0x117/0x330 [86.875426] __x64_sys_finit_module+0x77/0x100 [86.875440] x64_sys_call+0x24de/0x2660 [86.875454] do_syscall_64+0x91/0xe90 [86.875470] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.875486] other info that might help us debug this: [86.875502] Chain exists of: cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex [86.875539] Possible unsafe locking scenario: [86.875552] CPU0 CPU1 [86.875563] ---- ---- [86.875573] lock(reservation_ww_class_mutex); [86.875588] lock(reservation_ww_class_acquire); [86.875606] lock(reservation_ww_class_mutex); [86.875624] rlock(cpu_hotplug_lock); [86.875637] *** DEADLOCK *** [86.875650] 3 locks held by i915_module_loa/1432: [86.875663] #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220 [86.875699] #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.876512] #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.877305] stack backtrace: [86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G U 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary) [86.877334] Tainted: [U]=USER [86.877336] Hardware name: /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020 [86.877339] Call Trace: [86.877344] <TASK> [86.877353] dump_stack_lvl+0x91/0xf0 [86.877364] dump_stack+0x10/0x20 [86.877369] print_circular_bug+0x285/0x360 [86.877379] check_noncircular+0x135/0x150 [86.877390] __lock_acquire+0x1635/0x2810 [86.877403] lock_acquire+0xc4/0x2f0 [86.877408] ? stop_machine+0x1c/0x50 [86.877422] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878173] cpus_read_lock+0x41/0x100 [86.878182] ? stop_machine+0x1c/0x50 [86.878191] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878916] stop_machine+0x1c/0x50 [86.878927] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.879652] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.880375] __vma_bind+0x55/0x70 [i915] [86.881133] fence_work+0x26/0xa0 [i915] [86.881851] fence_notify+0xa1/0x140 [i915] [86.882566] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.883286] i915_sw_fence_commit+0x39/0x60 [i915] [86.884003] i915_vma_pin_ww+0x462/0x1360 [i915] [86.884756] ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915] [86.885513] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.886281] initial_plane_vma+0x307/0x840 [i915] [86.887049] intel_initial_plane_config+0x33f/0x670 [i915] [86.887819] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.888587] i915_driver_probe+0x7fa/0xe80 [i915] [86.889293] ? mutex_unlock+0x12/0x20 [86.889301] ? drm_privacy_screen_get+0x171/0x190 [86.889308] ? acpi_dev_found+0x66/0x80 [86.889321] i915_pci_probe+0xe6/0x220 [i915] [86.890038] local_pci_probe+0x47/0xb0 [86.890049] pci_device_probe+0xf3/0x260 [86.890058] really_probe+0xf1/0x3c0 [86.890067] __driver_probe_device+0x8c/0x180 [86.890072] driver_probe_device+0x24/0xd0 [86.890078] __driver_attach+0x10f/0x220 [86.890083] ? __pfx___driver_attach+0x10/0x10 [86.890088] bus_for_each_dev+0x7f/0xe0 [86.890097] driver_attach+0x1e/0x30 [86.890101] bus_add_driver+0x151/0x290 [86.890107] driver_register+0x5e/0x130 [86.890113] __pci_register_driver+0x7d/0x90 [86.890119] i915_pci_register_driver+0x23/0x30 [i915] [86.890833] i915_init+0x37/0x120 [i915] [86.891482] ? __pfx_i915_init+0x10/0x10 [i915] [86.892135] do_one_initcall+0x60/0x3f0 [86.892145] ? __kmalloc_cache_noprof+0x33f/0x470 [86.892157] do_init_module+0x97/0x2a0 [86.892164] load_module+0x2c54/0x2d80 [86.892168] ? __kernel_read+0x15c/0x300 [86.892185] ? kernel_read_file+0x2b1/0x320 [86.892195] init_module_from_file+0x96/0xe0 [86.892199] ? init_module_from_file+0x96/0xe0 [86.892211] idempotent_init_module+0x117/0x330 [86.892224] __x64_sys_finit_module+0x77/0x100 [86.892230] x64_sys_call+0x24de/0x2660 [86.892236] do_syscall_64+0x91/0xe90 [86.892243] ? irqentry_exit+0x77/0xb0 [86.892249] ? sysvec_apic_timer_interrupt+0x57/0xc0 [86.892256] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.892261] RIP: 0033:0x7303e1b2725d [86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48 [86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d [86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c [86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80 [86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0 [86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710 [86.892304] </TASK> Call asynchronous variant of dma_fence_work_commit() in that case. v3: Provide more verbose in-line comment (Andi), - mention target environments in commit message. Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985 Cc: Andi Shyti <[email protected]> Signed-off-by: Janusz Krzysztofik <[email protected]> Reviewed-by: Sebastian Brzezinka <[email protected]> Reviewed-by: Krzysztof Karas <[email protected]> Acked-by: Andi Shyti <[email protected]> Signed-off-by: Andi Shyti <[email protected]> Link: https://lore.kernel.org/r/[email protected] (cherry picked from commit 648ef13) Signed-off-by: Rodrigo Vivi <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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[ Upstream commit 84bbe32 ] On completion of i915_vma_pin_ww(), a synchronous variant of dma_fence_work_commit() is called. When pinning a VMA to GGTT address space on a Cherry View family processor, or on a Broxton generation SoC with VTD enabled, i.e., when stop_machine() is then called from intel_ggtt_bind_vma(), that can potentially lead to lock inversion among reservation_ww and cpu_hotplug locks. [86.861179] ====================================================== [86.861193] WARNING: possible circular locking dependency detected [86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G U [86.861226] ------------------------------------------------------ [86.861238] i915_module_loa/1432 is trying to acquire lock: [86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50 [86.861290] but task is already holding lock: [86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.862233] which lock already depends on the new lock. [86.862251] the existing dependency chain (in reverse order) is: [86.862265] -> #5 (reservation_ww_class_mutex){+.+.}-{3:3}: [86.862292] dma_resv_lockdep+0x19a/0x390 [86.862315] do_one_initcall+0x60/0x3f0 [86.862334] kernel_init_freeable+0x3cd/0x680 [86.862353] kernel_init+0x1b/0x200 [86.862369] ret_from_fork+0x47/0x70 [86.862383] ret_from_fork_asm+0x1a/0x30 [86.862399] -> #4 (reservation_ww_class_acquire){+.+.}-{0:0}: [86.862425] dma_resv_lockdep+0x178/0x390 [86.862440] do_one_initcall+0x60/0x3f0 [86.862454] kernel_init_freeable+0x3cd/0x680 [86.862470] kernel_init+0x1b/0x200 [86.862482] ret_from_fork+0x47/0x70 [86.862495] ret_from_fork_asm+0x1a/0x30 [86.862509] -> #3 (&mm->mmap_lock){++++}-{3:3}: [86.862531] down_read_killable+0x46/0x1e0 [86.862546] lock_mm_and_find_vma+0xa2/0x280 [86.862561] do_user_addr_fault+0x266/0x8e0 [86.862578] exc_page_fault+0x8a/0x2f0 [86.862593] asm_exc_page_fault+0x27/0x30 [86.862607] filldir64+0xeb/0x180 [86.862620] kernfs_fop_readdir+0x118/0x480 [86.862635] iterate_dir+0xcf/0x2b0 [86.862648] __x64_sys_getdents64+0x84/0x140 [86.862661] x64_sys_call+0x1058/0x2660 [86.862675] do_syscall_64+0x91/0xe90 [86.862689] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.862703] -> #2 (&root->kernfs_rwsem){++++}-{3:3}: [86.862725] down_write+0x3e/0xf0 [86.862738] kernfs_add_one+0x30/0x3c0 [86.862751] kernfs_create_dir_ns+0x53/0xb0 [86.862765] internal_create_group+0x134/0x4c0 [86.862779] sysfs_create_group+0x13/0x20 [86.862792] topology_add_dev+0x1d/0x30 [86.862806] cpuhp_invoke_callback+0x4b5/0x850 [86.862822] cpuhp_issue_call+0xbf/0x1f0 [86.862836] __cpuhp_setup_state_cpuslocked+0x111/0x320 [86.862852] __cpuhp_setup_state+0xb0/0x220 [86.862866] topology_sysfs_init+0x30/0x50 [86.862879] do_one_initcall+0x60/0x3f0 [86.862893] kernel_init_freeable+0x3cd/0x680 [86.862908] kernel_init+0x1b/0x200 [86.862921] ret_from_fork+0x47/0x70 [86.862934] ret_from_fork_asm+0x1a/0x30 [86.862947] -> #1 (cpuhp_state_mutex){+.+.}-{3:3}: [86.862969] __mutex_lock+0xaa/0xed0 [86.862982] mutex_lock_nested+0x1b/0x30 [86.862995] __cpuhp_setup_state_cpuslocked+0x67/0x320 [86.863012] __cpuhp_setup_state+0xb0/0x220 [86.863026] page_alloc_init_cpuhp+0x2d/0x60 [86.863041] mm_core_init+0x22/0x2d0 [86.863054] start_kernel+0x576/0xbd0 [86.863068] x86_64_start_reservations+0x18/0x30 [86.863084] x86_64_start_kernel+0xbf/0x110 [86.863098] common_startup_64+0x13e/0x141 [86.863114] -> #0 (cpu_hotplug_lock){++++}-{0:0}: [86.863135] __lock_acquire+0x1635/0x2810 [86.863152] lock_acquire+0xc4/0x2f0 [86.863166] cpus_read_lock+0x41/0x100 [86.863180] stop_machine+0x1c/0x50 [86.863194] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.863987] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.864735] __vma_bind+0x55/0x70 [i915] [86.865510] fence_work+0x26/0xa0 [i915] [86.866248] fence_notify+0xa1/0x140 [i915] [86.866983] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.867719] i915_sw_fence_commit+0x39/0x60 [i915] [86.868453] i915_vma_pin_ww+0x462/0x1360 [i915] [86.869228] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.870001] initial_plane_vma+0x307/0x840 [i915] [86.870774] intel_initial_plane_config+0x33f/0x670 [i915] [86.871546] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.872330] i915_driver_probe+0x7fa/0xe80 [i915] [86.873057] i915_pci_probe+0xe6/0x220 [i915] [86.873782] local_pci_probe+0x47/0xb0 [86.873802] pci_device_probe+0xf3/0x260 [86.873817] really_probe+0xf1/0x3c0 [86.873833] __driver_probe_device+0x8c/0x180 [86.873848] driver_probe_device+0x24/0xd0 [86.873862] __driver_attach+0x10f/0x220 [86.873876] bus_for_each_dev+0x7f/0xe0 [86.873892] driver_attach+0x1e/0x30 [86.873904] bus_add_driver+0x151/0x290 [86.873917] driver_register+0x5e/0x130 [86.873931] __pci_register_driver+0x7d/0x90 [86.873945] i915_pci_register_driver+0x23/0x30 [i915] [86.874678] i915_init+0x37/0x120 [i915] [86.875347] do_one_initcall+0x60/0x3f0 [86.875369] do_init_module+0x97/0x2a0 [86.875385] load_module+0x2c54/0x2d80 [86.875398] init_module_from_file+0x96/0xe0 [86.875413] idempotent_init_module+0x117/0x330 [86.875426] __x64_sys_finit_module+0x77/0x100 [86.875440] x64_sys_call+0x24de/0x2660 [86.875454] do_syscall_64+0x91/0xe90 [86.875470] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.875486] other info that might help us debug this: [86.875502] Chain exists of: cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex [86.875539] Possible unsafe locking scenario: [86.875552] CPU0 CPU1 [86.875563] ---- ---- [86.875573] lock(reservation_ww_class_mutex); [86.875588] lock(reservation_ww_class_acquire); [86.875606] lock(reservation_ww_class_mutex); [86.875624] rlock(cpu_hotplug_lock); [86.875637] *** DEADLOCK *** [86.875650] 3 locks held by i915_module_loa/1432: [86.875663] #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220 [86.875699] #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.876512] #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.877305] stack backtrace: [86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G U 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary) [86.877334] Tainted: [U]=USER [86.877336] Hardware name: /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020 [86.877339] Call Trace: [86.877344] <TASK> [86.877353] dump_stack_lvl+0x91/0xf0 [86.877364] dump_stack+0x10/0x20 [86.877369] print_circular_bug+0x285/0x360 [86.877379] check_noncircular+0x135/0x150 [86.877390] __lock_acquire+0x1635/0x2810 [86.877403] lock_acquire+0xc4/0x2f0 [86.877408] ? stop_machine+0x1c/0x50 [86.877422] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878173] cpus_read_lock+0x41/0x100 [86.878182] ? stop_machine+0x1c/0x50 [86.878191] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878916] stop_machine+0x1c/0x50 [86.878927] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.879652] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.880375] __vma_bind+0x55/0x70 [i915] [86.881133] fence_work+0x26/0xa0 [i915] [86.881851] fence_notify+0xa1/0x140 [i915] [86.882566] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.883286] i915_sw_fence_commit+0x39/0x60 [i915] [86.884003] i915_vma_pin_ww+0x462/0x1360 [i915] [86.884756] ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915] [86.885513] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.886281] initial_plane_vma+0x307/0x840 [i915] [86.887049] intel_initial_plane_config+0x33f/0x670 [i915] [86.887819] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.888587] i915_driver_probe+0x7fa/0xe80 [i915] [86.889293] ? mutex_unlock+0x12/0x20 [86.889301] ? drm_privacy_screen_get+0x171/0x190 [86.889308] ? acpi_dev_found+0x66/0x80 [86.889321] i915_pci_probe+0xe6/0x220 [i915] [86.890038] local_pci_probe+0x47/0xb0 [86.890049] pci_device_probe+0xf3/0x260 [86.890058] really_probe+0xf1/0x3c0 [86.890067] __driver_probe_device+0x8c/0x180 [86.890072] driver_probe_device+0x24/0xd0 [86.890078] __driver_attach+0x10f/0x220 [86.890083] ? __pfx___driver_attach+0x10/0x10 [86.890088] bus_for_each_dev+0x7f/0xe0 [86.890097] driver_attach+0x1e/0x30 [86.890101] bus_add_driver+0x151/0x290 [86.890107] driver_register+0x5e/0x130 [86.890113] __pci_register_driver+0x7d/0x90 [86.890119] i915_pci_register_driver+0x23/0x30 [i915] [86.890833] i915_init+0x37/0x120 [i915] [86.891482] ? __pfx_i915_init+0x10/0x10 [i915] [86.892135] do_one_initcall+0x60/0x3f0 [86.892145] ? __kmalloc_cache_noprof+0x33f/0x470 [86.892157] do_init_module+0x97/0x2a0 [86.892164] load_module+0x2c54/0x2d80 [86.892168] ? __kernel_read+0x15c/0x300 [86.892185] ? kernel_read_file+0x2b1/0x320 [86.892195] init_module_from_file+0x96/0xe0 [86.892199] ? init_module_from_file+0x96/0xe0 [86.892211] idempotent_init_module+0x117/0x330 [86.892224] __x64_sys_finit_module+0x77/0x100 [86.892230] x64_sys_call+0x24de/0x2660 [86.892236] do_syscall_64+0x91/0xe90 [86.892243] ? irqentry_exit+0x77/0xb0 [86.892249] ? sysvec_apic_timer_interrupt+0x57/0xc0 [86.892256] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.892261] RIP: 0033:0x7303e1b2725d [86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48 [86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d [86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c [86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80 [86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0 [86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710 [86.892304] </TASK> Call asynchronous variant of dma_fence_work_commit() in that case. v3: Provide more verbose in-line comment (Andi), - mention target environments in commit message. Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985 Cc: Andi Shyti <[email protected]> Signed-off-by: Janusz Krzysztofik <[email protected]> Reviewed-by: Sebastian Brzezinka <[email protected]> Reviewed-by: Krzysztof Karas <[email protected]> Acked-by: Andi Shyti <[email protected]> Signed-off-by: Andi Shyti <[email protected]> Link: https://lore.kernel.org/r/[email protected] (cherry picked from commit 648ef13) Signed-off-by: Rodrigo Vivi <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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[ Upstream commit 38f5024 ] With CONFIG_PROVE_RCU_LIST=y and by executing $ netcat -l --sctp & $ netcat --sctp localhost & $ ss --sctp one can trigger the following Lockdep-RCU splat(s): WARNING: suspicious RCU usage 6.18.0-rc1-00093-g7f864458e9a6 #5 Not tainted ----------------------------- net/sctp/diag.c:76 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by ss/215: #0: ffff9c740828bec0 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{4:4}, at: __netlink_dump_start+0x84/0x2b0 #1: ffff9c7401d72cd0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sock_dump+0x38/0x200 stack backtrace: CPU: 0 UID: 0 PID: 215 Comm: ss Not tainted 6.18.0-rc1-00093-g7f864458e9a6 #5 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x90 lockdep_rcu_suspicious.cold+0x4e/0xa3 inet_sctp_diag_fill.isra.0+0x4b1/0x5d0 sctp_sock_dump+0x131/0x200 sctp_transport_traverse_process+0x170/0x1b0 ? __pfx_sctp_sock_filter+0x10/0x10 ? __pfx_sctp_sock_dump+0x10/0x10 sctp_diag_dump+0x103/0x140 __inet_diag_dump+0x70/0xb0 netlink_dump+0x148/0x490 __netlink_dump_start+0x1f3/0x2b0 inet_diag_handler_cmd+0xcd/0x100 ? __pfx_inet_diag_dump_start+0x10/0x10 ? __pfx_inet_diag_dump+0x10/0x10 ? __pfx_inet_diag_dump_done+0x10/0x10 sock_diag_rcv_msg+0x18e/0x320 ? __pfx_sock_diag_rcv_msg+0x10/0x10 netlink_rcv_skb+0x4d/0x100 netlink_unicast+0x1d7/0x2b0 netlink_sendmsg+0x203/0x450 ____sys_sendmsg+0x30c/0x340 ___sys_sendmsg+0x94/0xf0 __sys_sendmsg+0x83/0xf0 do_syscall_64+0xbb/0x390 entry_SYSCALL_64_after_hwframe+0x77/0x7f ... </TASK> Fixes: 8f840e4 ("sctp: add the sctp_diag.c file") Signed-off-by: Stefan Wiehler <[email protected]> Reviewed-by: Kuniyuki Iwashima <[email protected]> Acked-by: Xin Long <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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[ Upstream commit 84bbe32 ] On completion of i915_vma_pin_ww(), a synchronous variant of dma_fence_work_commit() is called. When pinning a VMA to GGTT address space on a Cherry View family processor, or on a Broxton generation SoC with VTD enabled, i.e., when stop_machine() is then called from intel_ggtt_bind_vma(), that can potentially lead to lock inversion among reservation_ww and cpu_hotplug locks. [86.861179] ====================================================== [86.861193] WARNING: possible circular locking dependency detected [86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G U [86.861226] ------------------------------------------------------ [86.861238] i915_module_loa/1432 is trying to acquire lock: [86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50 [86.861290] but task is already holding lock: [86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.862233] which lock already depends on the new lock. [86.862251] the existing dependency chain (in reverse order) is: [86.862265] -> #5 (reservation_ww_class_mutex){+.+.}-{3:3}: [86.862292] dma_resv_lockdep+0x19a/0x390 [86.862315] do_one_initcall+0x60/0x3f0 [86.862334] kernel_init_freeable+0x3cd/0x680 [86.862353] kernel_init+0x1b/0x200 [86.862369] ret_from_fork+0x47/0x70 [86.862383] ret_from_fork_asm+0x1a/0x30 [86.862399] -> #4 (reservation_ww_class_acquire){+.+.}-{0:0}: [86.862425] dma_resv_lockdep+0x178/0x390 [86.862440] do_one_initcall+0x60/0x3f0 [86.862454] kernel_init_freeable+0x3cd/0x680 [86.862470] kernel_init+0x1b/0x200 [86.862482] ret_from_fork+0x47/0x70 [86.862495] ret_from_fork_asm+0x1a/0x30 [86.862509] -> #3 (&mm->mmap_lock){++++}-{3:3}: [86.862531] down_read_killable+0x46/0x1e0 [86.862546] lock_mm_and_find_vma+0xa2/0x280 [86.862561] do_user_addr_fault+0x266/0x8e0 [86.862578] exc_page_fault+0x8a/0x2f0 [86.862593] asm_exc_page_fault+0x27/0x30 [86.862607] filldir64+0xeb/0x180 [86.862620] kernfs_fop_readdir+0x118/0x480 [86.862635] iterate_dir+0xcf/0x2b0 [86.862648] __x64_sys_getdents64+0x84/0x140 [86.862661] x64_sys_call+0x1058/0x2660 [86.862675] do_syscall_64+0x91/0xe90 [86.862689] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.862703] -> #2 (&root->kernfs_rwsem){++++}-{3:3}: [86.862725] down_write+0x3e/0xf0 [86.862738] kernfs_add_one+0x30/0x3c0 [86.862751] kernfs_create_dir_ns+0x53/0xb0 [86.862765] internal_create_group+0x134/0x4c0 [86.862779] sysfs_create_group+0x13/0x20 [86.862792] topology_add_dev+0x1d/0x30 [86.862806] cpuhp_invoke_callback+0x4b5/0x850 [86.862822] cpuhp_issue_call+0xbf/0x1f0 [86.862836] __cpuhp_setup_state_cpuslocked+0x111/0x320 [86.862852] __cpuhp_setup_state+0xb0/0x220 [86.862866] topology_sysfs_init+0x30/0x50 [86.862879] do_one_initcall+0x60/0x3f0 [86.862893] kernel_init_freeable+0x3cd/0x680 [86.862908] kernel_init+0x1b/0x200 [86.862921] ret_from_fork+0x47/0x70 [86.862934] ret_from_fork_asm+0x1a/0x30 [86.862947] -> #1 (cpuhp_state_mutex){+.+.}-{3:3}: [86.862969] __mutex_lock+0xaa/0xed0 [86.862982] mutex_lock_nested+0x1b/0x30 [86.862995] __cpuhp_setup_state_cpuslocked+0x67/0x320 [86.863012] __cpuhp_setup_state+0xb0/0x220 [86.863026] page_alloc_init_cpuhp+0x2d/0x60 [86.863041] mm_core_init+0x22/0x2d0 [86.863054] start_kernel+0x576/0xbd0 [86.863068] x86_64_start_reservations+0x18/0x30 [86.863084] x86_64_start_kernel+0xbf/0x110 [86.863098] common_startup_64+0x13e/0x141 [86.863114] -> #0 (cpu_hotplug_lock){++++}-{0:0}: [86.863135] __lock_acquire+0x1635/0x2810 [86.863152] lock_acquire+0xc4/0x2f0 [86.863166] cpus_read_lock+0x41/0x100 [86.863180] stop_machine+0x1c/0x50 [86.863194] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.863987] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.864735] __vma_bind+0x55/0x70 [i915] [86.865510] fence_work+0x26/0xa0 [i915] [86.866248] fence_notify+0xa1/0x140 [i915] [86.866983] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.867719] i915_sw_fence_commit+0x39/0x60 [i915] [86.868453] i915_vma_pin_ww+0x462/0x1360 [i915] [86.869228] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.870001] initial_plane_vma+0x307/0x840 [i915] [86.870774] intel_initial_plane_config+0x33f/0x670 [i915] [86.871546] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.872330] i915_driver_probe+0x7fa/0xe80 [i915] [86.873057] i915_pci_probe+0xe6/0x220 [i915] [86.873782] local_pci_probe+0x47/0xb0 [86.873802] pci_device_probe+0xf3/0x260 [86.873817] really_probe+0xf1/0x3c0 [86.873833] __driver_probe_device+0x8c/0x180 [86.873848] driver_probe_device+0x24/0xd0 [86.873862] __driver_attach+0x10f/0x220 [86.873876] bus_for_each_dev+0x7f/0xe0 [86.873892] driver_attach+0x1e/0x30 [86.873904] bus_add_driver+0x151/0x290 [86.873917] driver_register+0x5e/0x130 [86.873931] __pci_register_driver+0x7d/0x90 [86.873945] i915_pci_register_driver+0x23/0x30 [i915] [86.874678] i915_init+0x37/0x120 [i915] [86.875347] do_one_initcall+0x60/0x3f0 [86.875369] do_init_module+0x97/0x2a0 [86.875385] load_module+0x2c54/0x2d80 [86.875398] init_module_from_file+0x96/0xe0 [86.875413] idempotent_init_module+0x117/0x330 [86.875426] __x64_sys_finit_module+0x77/0x100 [86.875440] x64_sys_call+0x24de/0x2660 [86.875454] do_syscall_64+0x91/0xe90 [86.875470] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.875486] other info that might help us debug this: [86.875502] Chain exists of: cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex [86.875539] Possible unsafe locking scenario: [86.875552] CPU0 CPU1 [86.875563] ---- ---- [86.875573] lock(reservation_ww_class_mutex); [86.875588] lock(reservation_ww_class_acquire); [86.875606] lock(reservation_ww_class_mutex); [86.875624] rlock(cpu_hotplug_lock); [86.875637] *** DEADLOCK *** [86.875650] 3 locks held by i915_module_loa/1432: [86.875663] #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220 [86.875699] #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.876512] #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.877305] stack backtrace: [86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G U 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary) [86.877334] Tainted: [U]=USER [86.877336] Hardware name: /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020 [86.877339] Call Trace: [86.877344] <TASK> [86.877353] dump_stack_lvl+0x91/0xf0 [86.877364] dump_stack+0x10/0x20 [86.877369] print_circular_bug+0x285/0x360 [86.877379] check_noncircular+0x135/0x150 [86.877390] __lock_acquire+0x1635/0x2810 [86.877403] lock_acquire+0xc4/0x2f0 [86.877408] ? stop_machine+0x1c/0x50 [86.877422] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878173] cpus_read_lock+0x41/0x100 [86.878182] ? stop_machine+0x1c/0x50 [86.878191] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878916] stop_machine+0x1c/0x50 [86.878927] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.879652] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.880375] __vma_bind+0x55/0x70 [i915] [86.881133] fence_work+0x26/0xa0 [i915] [86.881851] fence_notify+0xa1/0x140 [i915] [86.882566] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.883286] i915_sw_fence_commit+0x39/0x60 [i915] [86.884003] i915_vma_pin_ww+0x462/0x1360 [i915] [86.884756] ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915] [86.885513] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.886281] initial_plane_vma+0x307/0x840 [i915] [86.887049] intel_initial_plane_config+0x33f/0x670 [i915] [86.887819] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.888587] i915_driver_probe+0x7fa/0xe80 [i915] [86.889293] ? mutex_unlock+0x12/0x20 [86.889301] ? drm_privacy_screen_get+0x171/0x190 [86.889308] ? acpi_dev_found+0x66/0x80 [86.889321] i915_pci_probe+0xe6/0x220 [i915] [86.890038] local_pci_probe+0x47/0xb0 [86.890049] pci_device_probe+0xf3/0x260 [86.890058] really_probe+0xf1/0x3c0 [86.890067] __driver_probe_device+0x8c/0x180 [86.890072] driver_probe_device+0x24/0xd0 [86.890078] __driver_attach+0x10f/0x220 [86.890083] ? __pfx___driver_attach+0x10/0x10 [86.890088] bus_for_each_dev+0x7f/0xe0 [86.890097] driver_attach+0x1e/0x30 [86.890101] bus_add_driver+0x151/0x290 [86.890107] driver_register+0x5e/0x130 [86.890113] __pci_register_driver+0x7d/0x90 [86.890119] i915_pci_register_driver+0x23/0x30 [i915] [86.890833] i915_init+0x37/0x120 [i915] [86.891482] ? __pfx_i915_init+0x10/0x10 [i915] [86.892135] do_one_initcall+0x60/0x3f0 [86.892145] ? __kmalloc_cache_noprof+0x33f/0x470 [86.892157] do_init_module+0x97/0x2a0 [86.892164] load_module+0x2c54/0x2d80 [86.892168] ? __kernel_read+0x15c/0x300 [86.892185] ? kernel_read_file+0x2b1/0x320 [86.892195] init_module_from_file+0x96/0xe0 [86.892199] ? init_module_from_file+0x96/0xe0 [86.892211] idempotent_init_module+0x117/0x330 [86.892224] __x64_sys_finit_module+0x77/0x100 [86.892230] x64_sys_call+0x24de/0x2660 [86.892236] do_syscall_64+0x91/0xe90 [86.892243] ? irqentry_exit+0x77/0xb0 [86.892249] ? sysvec_apic_timer_interrupt+0x57/0xc0 [86.892256] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.892261] RIP: 0033:0x7303e1b2725d [86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48 [86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d [86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c [86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80 [86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0 [86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710 [86.892304] </TASK> Call asynchronous variant of dma_fence_work_commit() in that case. v3: Provide more verbose in-line comment (Andi), - mention target environments in commit message. Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985 Cc: Andi Shyti <[email protected]> Signed-off-by: Janusz Krzysztofik <[email protected]> Reviewed-by: Sebastian Brzezinka <[email protected]> Reviewed-by: Krzysztof Karas <[email protected]> Acked-by: Andi Shyti <[email protected]> Signed-off-by: Andi Shyti <[email protected]> Link: https://lore.kernel.org/r/[email protected] (cherry picked from commit 648ef13) Signed-off-by: Rodrigo Vivi <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
shaoyingxu
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Dec 3, 2025
[ Upstream commit 38f5024 ] With CONFIG_PROVE_RCU_LIST=y and by executing $ netcat -l --sctp & $ netcat --sctp localhost & $ ss --sctp one can trigger the following Lockdep-RCU splat(s): WARNING: suspicious RCU usage 6.18.0-rc1-00093-g7f864458e9a6 #5 Not tainted ----------------------------- net/sctp/diag.c:76 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by ss/215: #0: ffff9c740828bec0 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{4:4}, at: __netlink_dump_start+0x84/0x2b0 #1: ffff9c7401d72cd0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sock_dump+0x38/0x200 stack backtrace: CPU: 0 UID: 0 PID: 215 Comm: ss Not tainted 6.18.0-rc1-00093-g7f864458e9a6 #5 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x90 lockdep_rcu_suspicious.cold+0x4e/0xa3 inet_sctp_diag_fill.isra.0+0x4b1/0x5d0 sctp_sock_dump+0x131/0x200 sctp_transport_traverse_process+0x170/0x1b0 ? __pfx_sctp_sock_filter+0x10/0x10 ? __pfx_sctp_sock_dump+0x10/0x10 sctp_diag_dump+0x103/0x140 __inet_diag_dump+0x70/0xb0 netlink_dump+0x148/0x490 __netlink_dump_start+0x1f3/0x2b0 inet_diag_handler_cmd+0xcd/0x100 ? __pfx_inet_diag_dump_start+0x10/0x10 ? __pfx_inet_diag_dump+0x10/0x10 ? __pfx_inet_diag_dump_done+0x10/0x10 sock_diag_rcv_msg+0x18e/0x320 ? __pfx_sock_diag_rcv_msg+0x10/0x10 netlink_rcv_skb+0x4d/0x100 netlink_unicast+0x1d7/0x2b0 netlink_sendmsg+0x203/0x450 ____sys_sendmsg+0x30c/0x340 ___sys_sendmsg+0x94/0xf0 __sys_sendmsg+0x83/0xf0 do_syscall_64+0xbb/0x390 entry_SYSCALL_64_after_hwframe+0x77/0x7f ... </TASK> Fixes: 8f840e4 ("sctp: add the sctp_diag.c file") Signed-off-by: Stefan Wiehler <[email protected]> Reviewed-by: Kuniyuki Iwashima <[email protected]> Acked-by: Xin Long <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
heynemax
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Dec 4, 2025
Evaluate _DSM Function #5, the "PCI Boot Configuration" function. If the result is 0, the OS should preserve any resource assignments made by the firmware. Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Benjamin Herrenschmidt <[email protected]> [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas <[email protected]> (cherry picked from commit a78cf96)
heynemax
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Dec 4, 2025
commit 8410f70 upstream. Our test report a UAF: [ 2073.019181] ================================================================== [ 2073.019188] BUG: KASAN: use-after-free in __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019191] Write of size 8 at addr ffff8000ccf64128 by task rmmod/72584 [ 2073.019192] [ 2073.019196] CPU: 0 PID: 72584 Comm: rmmod Kdump: loaded Not tainted 4.19.90-yk #5 [ 2073.019198] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 2073.019200] Call trace: [ 2073.019203] dump_backtrace+0x0/0x310 [ 2073.019206] show_stack+0x28/0x38 [ 2073.019210] dump_stack+0xec/0x15c [ 2073.019216] print_address_description+0x68/0x2d0 [ 2073.019220] kasan_report+0x238/0x2f0 [ 2073.019224] __asan_store8+0x88/0xb0 [ 2073.019229] __bfq_put_async_bfqq+0xa0/0x168 [ 2073.019233] bfq_put_async_queues+0xbc/0x208 [ 2073.019236] bfq_pd_offline+0x178/0x238 [ 2073.019240] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019244] bfq_exit_queue+0x128/0x178 [ 2073.019249] blk_mq_exit_sched+0x12c/0x160 [ 2073.019252] elevator_exit+0xc8/0xd0 [ 2073.019256] blk_exit_queue+0x50/0x88 [ 2073.019259] blk_cleanup_queue+0x228/0x3d8 [ 2073.019267] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019274] null_exit+0x90/0x114 [null_blk] [ 2073.019278] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019282] el0_svc_common+0xc8/0x320 [ 2073.019287] el0_svc_handler+0xf8/0x160 [ 2073.019290] el0_svc+0x10/0x218 [ 2073.019291] [ 2073.019294] Allocated by task 14163: [ 2073.019301] kasan_kmalloc+0xe0/0x190 [ 2073.019305] kmem_cache_alloc_node_trace+0x1cc/0x418 [ 2073.019308] bfq_pd_alloc+0x54/0x118 [ 2073.019313] blkcg_activate_policy+0x250/0x460 [ 2073.019317] bfq_create_group_hierarchy+0x38/0x110 [ 2073.019321] bfq_init_queue+0x6d0/0x948 [ 2073.019325] blk_mq_init_sched+0x1d8/0x390 [ 2073.019330] elevator_switch_mq+0x88/0x170 [ 2073.019334] elevator_switch+0x140/0x270 [ 2073.019338] elv_iosched_store+0x1a4/0x2a0 [ 2073.019342] queue_attr_store+0x90/0xe0 [ 2073.019348] sysfs_kf_write+0xa8/0xe8 [ 2073.019351] kernfs_fop_write+0x1f8/0x378 [ 2073.019359] __vfs_write+0xe0/0x360 [ 2073.019363] vfs_write+0xf0/0x270 [ 2073.019367] ksys_write+0xdc/0x1b8 [ 2073.019371] __arm64_sys_write+0x50/0x60 [ 2073.019375] el0_svc_common+0xc8/0x320 [ 2073.019380] el0_svc_handler+0xf8/0x160 [ 2073.019383] el0_svc+0x10/0x218 [ 2073.019385] [ 2073.019387] Freed by task 72584: [ 2073.019391] __kasan_slab_free+0x120/0x228 [ 2073.019394] kasan_slab_free+0x10/0x18 [ 2073.019397] kfree+0x94/0x368 [ 2073.019400] bfqg_put+0x64/0xb0 [ 2073.019404] bfqg_and_blkg_put+0x90/0xb0 [ 2073.019408] bfq_put_queue+0x220/0x228 [ 2073.019413] __bfq_put_async_bfqq+0x98/0x168 [ 2073.019416] bfq_put_async_queues+0xbc/0x208 [ 2073.019420] bfq_pd_offline+0x178/0x238 [ 2073.019424] blkcg_deactivate_policy+0x1f0/0x420 [ 2073.019429] bfq_exit_queue+0x128/0x178 [ 2073.019433] blk_mq_exit_sched+0x12c/0x160 [ 2073.019437] elevator_exit+0xc8/0xd0 [ 2073.019440] blk_exit_queue+0x50/0x88 [ 2073.019443] blk_cleanup_queue+0x228/0x3d8 [ 2073.019451] null_del_dev+0xfc/0x1e0 [null_blk] [ 2073.019459] null_exit+0x90/0x114 [null_blk] [ 2073.019462] __arm64_sys_delete_module+0x358/0x5a0 [ 2073.019467] el0_svc_common+0xc8/0x320 [ 2073.019471] el0_svc_handler+0xf8/0x160 [ 2073.019474] el0_svc+0x10/0x218 [ 2073.019475] [ 2073.019479] The buggy address belongs to the object at ffff8000ccf63f00 which belongs to the cache kmalloc-1024 of size 1024 [ 2073.019484] The buggy address is located 552 bytes inside of 1024-byte region [ffff8000ccf63f00, ffff8000ccf64300) [ 2073.019486] The buggy address belongs to the page: [ 2073.019492] page:ffff7e000333d800 count:1 mapcount:0 mapping:ffff8000c0003a00 index:0x0 compound_mapcount: 0 [ 2073.020123] flags: 0x7ffff0000008100(slab|head) [ 2073.020403] raw: 07ffff0000008100 ffff7e0003334c08 ffff7e00001f5a08 ffff8000c0003a00 [ 2073.020409] raw: 0000000000000000 00000000001c001c 00000001ffffffff 0000000000000000 [ 2073.020411] page dumped because: kasan: bad access detected [ 2073.020412] [ 2073.020414] Memory state around the buggy address: [ 2073.020420] ffff8000ccf64000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020424] ffff8000ccf64080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020428] >ffff8000ccf64100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020430] ^ [ 2073.020434] ffff8000ccf64180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020438] ffff8000ccf64200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 2073.020439] ================================================================== The same problem exist in mainline as well. This is because oom_bfqq is moved to a non-root group, thus root_group is freed earlier. Thus fix the problem by don't move oom_bfqq. Signed-off-by: Yu Kuai <[email protected]> Reviewed-by: Jan Kara <[email protected]> Acked-by: Paolo Valente <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Andrew Paniakin <[email protected]>
shaoyingxu
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Dec 4, 2025
Marc Kleine-Budde <[email protected]> says: Similarly to how CAN FD reuses the bittiming logic of Classical CAN, CAN XL also reuses the entirety of CAN FD features, and, on top of that, adds new features which are specific to CAN XL. A so-called 'mixed-mode' is intended to have (XL-tolerant) CAN FD nodes and CAN XL nodes on one CAN segment, where the FD-controllers can talk CC/FD and the XL-controllers can talk CC/FD/XL. This mixed-mode utilizes the known error-signalling (ES) for sending CC/FD/XL frames. For CAN FD and CAN XL the tranceiver delay compensation (TDC) is supported to use common CAN and CAN-SIG transceivers. The CANXL-only mode disables the error-signalling in the CAN XL controller. This mode does not allow CC/FD frames to be sent but additionally offers a CAN XL transceiver mode switching (TMS) to send CAN XL frames with up to 20Mbit/s data rate. The TMS utilizes a PWM configuration which is added to the netlink interface. Configured with CAN_CTRLMODE_FD and CAN_CTRLMODE_XL this leads to: FD=0 XL=0 CC-only mode (ES=1) FD=1 XL=0 FD/CC mixed-mode (ES=1) FD=1 XL=1 XL/FD/CC mixed-mode (ES=1) FD=0 XL=1 XL-only mode (ES=0, TMS optional) Patch #1 print defined ctrlmode strings capitalized to increase the readability and to be in line with the 'ip' tool (iproute2). Patch #2 is a small clean-up which makes can_calc_bittiming() use NL_SET_ERR_MSG() instead of netdev_err(). Patch #3 adds a check in can_dev_dropped_skb() to drop CAN FD frames when CAN FD is turned off. Patch #4 adds CAN_CTRLMODE_RESTRICTED. Note that contrary to the other CAN_CTRL_MODE_XL_* that are introduced in the later patches, this control mode is not specific to CAN XL. The nuance is that because this restricted mode was only added in ISO 11898-1:2024, it is made mandatory for CAN XL devices but optional for other protocols. This is why this patch is added as a preparation before introducing the core CAN XL logic. Patch #5 adds all the CAN XL features which are inherited from CAN FD: the nominal bittiming, the data bittiming and the TDC. Patch gregkh#6 add a new CAN_CTRLMODE_XL_TMS control mode which is specific to CAN XL to enable the transceiver mode switching (TMS) in XL-only mode. Patch gregkh#7 adds a check in can_dev_dropped_skb() to drop CAN CC/FD frames when the CAN XL controller is in CAN XL-only mode. The introduced can_dev_in_xl_only_mode() function also determines the error-signalling configuration for the CAN XL controllers. Patch gregkh#8 to gregkh#11 add the PWM logic for the CAN XL TMS mode. Patch gregkh#12 to gregkh#14 add different default sample-points for standard CAN and CAN SIG transceivers (with TDC) and CAN XL transceivers using PWM in the CAN XL TMS mode. Patch gregkh#15 add a dummy_can driver for netlink testing and debugging. Patch gregkh#16 check CAN frame type (CC/FD/XL) when writing those frames to the CAN_RAW socket and reject them if it's not supported by the CAN interface. Patch gregkh#17 increase the resolution when printing the bitrate error and round-up the value to 0.01% in the case the resolution would still provide values which would lead to 0.00%. Link: https://patch.msgid.link/[email protected] Signed-off-by: Marc Kleine-Budde <[email protected]>
paniakin-aws
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Dec 7, 2025
[ Upstream commit 38f5024 ] With CONFIG_PROVE_RCU_LIST=y and by executing $ netcat -l --sctp & $ netcat --sctp localhost & $ ss --sctp one can trigger the following Lockdep-RCU splat(s): WARNING: suspicious RCU usage 6.18.0-rc1-00093-g7f864458e9a6 #5 Not tainted ----------------------------- net/sctp/diag.c:76 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by ss/215: #0: ffff9c740828bec0 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{4:4}, at: __netlink_dump_start+0x84/0x2b0 #1: ffff9c7401d72cd0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sock_dump+0x38/0x200 stack backtrace: CPU: 0 UID: 0 PID: 215 Comm: ss Not tainted 6.18.0-rc1-00093-g7f864458e9a6 #5 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x90 lockdep_rcu_suspicious.cold+0x4e/0xa3 inet_sctp_diag_fill.isra.0+0x4b1/0x5d0 sctp_sock_dump+0x131/0x200 sctp_transport_traverse_process+0x170/0x1b0 ? __pfx_sctp_sock_filter+0x10/0x10 ? __pfx_sctp_sock_dump+0x10/0x10 sctp_diag_dump+0x103/0x140 __inet_diag_dump+0x70/0xb0 netlink_dump+0x148/0x490 __netlink_dump_start+0x1f3/0x2b0 inet_diag_handler_cmd+0xcd/0x100 ? __pfx_inet_diag_dump_start+0x10/0x10 ? __pfx_inet_diag_dump+0x10/0x10 ? __pfx_inet_diag_dump_done+0x10/0x10 sock_diag_rcv_msg+0x18e/0x320 ? __pfx_sock_diag_rcv_msg+0x10/0x10 netlink_rcv_skb+0x4d/0x100 netlink_unicast+0x1d7/0x2b0 netlink_sendmsg+0x203/0x450 ____sys_sendmsg+0x30c/0x340 ___sys_sendmsg+0x94/0xf0 __sys_sendmsg+0x83/0xf0 do_syscall_64+0xbb/0x390 entry_SYSCALL_64_after_hwframe+0x77/0x7f ... </TASK> Fixes: 8f840e4 ("sctp: add the sctp_diag.c file") Signed-off-by: Stefan Wiehler <[email protected]> Reviewed-by: Kuniyuki Iwashima <[email protected]> Acked-by: Xin Long <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
paniakin-aws
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[ Upstream commit 38f5024 ] With CONFIG_PROVE_RCU_LIST=y and by executing $ netcat -l --sctp & $ netcat --sctp localhost & $ ss --sctp one can trigger the following Lockdep-RCU splat(s): WARNING: suspicious RCU usage 6.18.0-rc1-00093-g7f864458e9a6 #5 Not tainted ----------------------------- net/sctp/diag.c:76 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by ss/215: #0: ffff9c740828bec0 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{4:4}, at: __netlink_dump_start+0x84/0x2b0 #1: ffff9c7401d72cd0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sock_dump+0x38/0x200 stack backtrace: CPU: 0 UID: 0 PID: 215 Comm: ss Not tainted 6.18.0-rc1-00093-g7f864458e9a6 #5 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x90 lockdep_rcu_suspicious.cold+0x4e/0xa3 inet_sctp_diag_fill.isra.0+0x4b1/0x5d0 sctp_sock_dump+0x131/0x200 sctp_transport_traverse_process+0x170/0x1b0 ? __pfx_sctp_sock_filter+0x10/0x10 ? __pfx_sctp_sock_dump+0x10/0x10 sctp_diag_dump+0x103/0x140 __inet_diag_dump+0x70/0xb0 netlink_dump+0x148/0x490 __netlink_dump_start+0x1f3/0x2b0 inet_diag_handler_cmd+0xcd/0x100 ? __pfx_inet_diag_dump_start+0x10/0x10 ? __pfx_inet_diag_dump+0x10/0x10 ? __pfx_inet_diag_dump_done+0x10/0x10 sock_diag_rcv_msg+0x18e/0x320 ? __pfx_sock_diag_rcv_msg+0x10/0x10 netlink_rcv_skb+0x4d/0x100 netlink_unicast+0x1d7/0x2b0 netlink_sendmsg+0x203/0x450 ____sys_sendmsg+0x30c/0x340 ___sys_sendmsg+0x94/0xf0 __sys_sendmsg+0x83/0xf0 do_syscall_64+0xbb/0x390 entry_SYSCALL_64_after_hwframe+0x77/0x7f ... </TASK> Fixes: 8f840e4 ("sctp: add the sctp_diag.c file") Signed-off-by: Stefan Wiehler <[email protected]> Reviewed-by: Kuniyuki Iwashima <[email protected]> Acked-by: Xin Long <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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[ Upstream commit 84bbe32 ] On completion of i915_vma_pin_ww(), a synchronous variant of dma_fence_work_commit() is called. When pinning a VMA to GGTT address space on a Cherry View family processor, or on a Broxton generation SoC with VTD enabled, i.e., when stop_machine() is then called from intel_ggtt_bind_vma(), that can potentially lead to lock inversion among reservation_ww and cpu_hotplug locks. [86.861179] ====================================================== [86.861193] WARNING: possible circular locking dependency detected [86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G U [86.861226] ------------------------------------------------------ [86.861238] i915_module_loa/1432 is trying to acquire lock: [86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50 [86.861290] but task is already holding lock: [86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.862233] which lock already depends on the new lock. [86.862251] the existing dependency chain (in reverse order) is: [86.862265] -> #5 (reservation_ww_class_mutex){+.+.}-{3:3}: [86.862292] dma_resv_lockdep+0x19a/0x390 [86.862315] do_one_initcall+0x60/0x3f0 [86.862334] kernel_init_freeable+0x3cd/0x680 [86.862353] kernel_init+0x1b/0x200 [86.862369] ret_from_fork+0x47/0x70 [86.862383] ret_from_fork_asm+0x1a/0x30 [86.862399] -> #4 (reservation_ww_class_acquire){+.+.}-{0:0}: [86.862425] dma_resv_lockdep+0x178/0x390 [86.862440] do_one_initcall+0x60/0x3f0 [86.862454] kernel_init_freeable+0x3cd/0x680 [86.862470] kernel_init+0x1b/0x200 [86.862482] ret_from_fork+0x47/0x70 [86.862495] ret_from_fork_asm+0x1a/0x30 [86.862509] -> #3 (&mm->mmap_lock){++++}-{3:3}: [86.862531] down_read_killable+0x46/0x1e0 [86.862546] lock_mm_and_find_vma+0xa2/0x280 [86.862561] do_user_addr_fault+0x266/0x8e0 [86.862578] exc_page_fault+0x8a/0x2f0 [86.862593] asm_exc_page_fault+0x27/0x30 [86.862607] filldir64+0xeb/0x180 [86.862620] kernfs_fop_readdir+0x118/0x480 [86.862635] iterate_dir+0xcf/0x2b0 [86.862648] __x64_sys_getdents64+0x84/0x140 [86.862661] x64_sys_call+0x1058/0x2660 [86.862675] do_syscall_64+0x91/0xe90 [86.862689] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.862703] -> #2 (&root->kernfs_rwsem){++++}-{3:3}: [86.862725] down_write+0x3e/0xf0 [86.862738] kernfs_add_one+0x30/0x3c0 [86.862751] kernfs_create_dir_ns+0x53/0xb0 [86.862765] internal_create_group+0x134/0x4c0 [86.862779] sysfs_create_group+0x13/0x20 [86.862792] topology_add_dev+0x1d/0x30 [86.862806] cpuhp_invoke_callback+0x4b5/0x850 [86.862822] cpuhp_issue_call+0xbf/0x1f0 [86.862836] __cpuhp_setup_state_cpuslocked+0x111/0x320 [86.862852] __cpuhp_setup_state+0xb0/0x220 [86.862866] topology_sysfs_init+0x30/0x50 [86.862879] do_one_initcall+0x60/0x3f0 [86.862893] kernel_init_freeable+0x3cd/0x680 [86.862908] kernel_init+0x1b/0x200 [86.862921] ret_from_fork+0x47/0x70 [86.862934] ret_from_fork_asm+0x1a/0x30 [86.862947] -> #1 (cpuhp_state_mutex){+.+.}-{3:3}: [86.862969] __mutex_lock+0xaa/0xed0 [86.862982] mutex_lock_nested+0x1b/0x30 [86.862995] __cpuhp_setup_state_cpuslocked+0x67/0x320 [86.863012] __cpuhp_setup_state+0xb0/0x220 [86.863026] page_alloc_init_cpuhp+0x2d/0x60 [86.863041] mm_core_init+0x22/0x2d0 [86.863054] start_kernel+0x576/0xbd0 [86.863068] x86_64_start_reservations+0x18/0x30 [86.863084] x86_64_start_kernel+0xbf/0x110 [86.863098] common_startup_64+0x13e/0x141 [86.863114] -> #0 (cpu_hotplug_lock){++++}-{0:0}: [86.863135] __lock_acquire+0x1635/0x2810 [86.863152] lock_acquire+0xc4/0x2f0 [86.863166] cpus_read_lock+0x41/0x100 [86.863180] stop_machine+0x1c/0x50 [86.863194] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.863987] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.864735] __vma_bind+0x55/0x70 [i915] [86.865510] fence_work+0x26/0xa0 [i915] [86.866248] fence_notify+0xa1/0x140 [i915] [86.866983] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.867719] i915_sw_fence_commit+0x39/0x60 [i915] [86.868453] i915_vma_pin_ww+0x462/0x1360 [i915] [86.869228] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.870001] initial_plane_vma+0x307/0x840 [i915] [86.870774] intel_initial_plane_config+0x33f/0x670 [i915] [86.871546] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.872330] i915_driver_probe+0x7fa/0xe80 [i915] [86.873057] i915_pci_probe+0xe6/0x220 [i915] [86.873782] local_pci_probe+0x47/0xb0 [86.873802] pci_device_probe+0xf3/0x260 [86.873817] really_probe+0xf1/0x3c0 [86.873833] __driver_probe_device+0x8c/0x180 [86.873848] driver_probe_device+0x24/0xd0 [86.873862] __driver_attach+0x10f/0x220 [86.873876] bus_for_each_dev+0x7f/0xe0 [86.873892] driver_attach+0x1e/0x30 [86.873904] bus_add_driver+0x151/0x290 [86.873917] driver_register+0x5e/0x130 [86.873931] __pci_register_driver+0x7d/0x90 [86.873945] i915_pci_register_driver+0x23/0x30 [i915] [86.874678] i915_init+0x37/0x120 [i915] [86.875347] do_one_initcall+0x60/0x3f0 [86.875369] do_init_module+0x97/0x2a0 [86.875385] load_module+0x2c54/0x2d80 [86.875398] init_module_from_file+0x96/0xe0 [86.875413] idempotent_init_module+0x117/0x330 [86.875426] __x64_sys_finit_module+0x77/0x100 [86.875440] x64_sys_call+0x24de/0x2660 [86.875454] do_syscall_64+0x91/0xe90 [86.875470] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.875486] other info that might help us debug this: [86.875502] Chain exists of: cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex [86.875539] Possible unsafe locking scenario: [86.875552] CPU0 CPU1 [86.875563] ---- ---- [86.875573] lock(reservation_ww_class_mutex); [86.875588] lock(reservation_ww_class_acquire); [86.875606] lock(reservation_ww_class_mutex); [86.875624] rlock(cpu_hotplug_lock); [86.875637] *** DEADLOCK *** [86.875650] 3 locks held by i915_module_loa/1432: [86.875663] #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220 [86.875699] #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.876512] #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.877305] stack backtrace: [86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G U 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary) [86.877334] Tainted: [U]=USER [86.877336] Hardware name: /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020 [86.877339] Call Trace: [86.877344] <TASK> [86.877353] dump_stack_lvl+0x91/0xf0 [86.877364] dump_stack+0x10/0x20 [86.877369] print_circular_bug+0x285/0x360 [86.877379] check_noncircular+0x135/0x150 [86.877390] __lock_acquire+0x1635/0x2810 [86.877403] lock_acquire+0xc4/0x2f0 [86.877408] ? stop_machine+0x1c/0x50 [86.877422] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878173] cpus_read_lock+0x41/0x100 [86.878182] ? stop_machine+0x1c/0x50 [86.878191] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878916] stop_machine+0x1c/0x50 [86.878927] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.879652] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.880375] __vma_bind+0x55/0x70 [i915] [86.881133] fence_work+0x26/0xa0 [i915] [86.881851] fence_notify+0xa1/0x140 [i915] [86.882566] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.883286] i915_sw_fence_commit+0x39/0x60 [i915] [86.884003] i915_vma_pin_ww+0x462/0x1360 [i915] [86.884756] ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915] [86.885513] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.886281] initial_plane_vma+0x307/0x840 [i915] [86.887049] intel_initial_plane_config+0x33f/0x670 [i915] [86.887819] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.888587] i915_driver_probe+0x7fa/0xe80 [i915] [86.889293] ? mutex_unlock+0x12/0x20 [86.889301] ? drm_privacy_screen_get+0x171/0x190 [86.889308] ? acpi_dev_found+0x66/0x80 [86.889321] i915_pci_probe+0xe6/0x220 [i915] [86.890038] local_pci_probe+0x47/0xb0 [86.890049] pci_device_probe+0xf3/0x260 [86.890058] really_probe+0xf1/0x3c0 [86.890067] __driver_probe_device+0x8c/0x180 [86.890072] driver_probe_device+0x24/0xd0 [86.890078] __driver_attach+0x10f/0x220 [86.890083] ? __pfx___driver_attach+0x10/0x10 [86.890088] bus_for_each_dev+0x7f/0xe0 [86.890097] driver_attach+0x1e/0x30 [86.890101] bus_add_driver+0x151/0x290 [86.890107] driver_register+0x5e/0x130 [86.890113] __pci_register_driver+0x7d/0x90 [86.890119] i915_pci_register_driver+0x23/0x30 [i915] [86.890833] i915_init+0x37/0x120 [i915] [86.891482] ? __pfx_i915_init+0x10/0x10 [i915] [86.892135] do_one_initcall+0x60/0x3f0 [86.892145] ? __kmalloc_cache_noprof+0x33f/0x470 [86.892157] do_init_module+0x97/0x2a0 [86.892164] load_module+0x2c54/0x2d80 [86.892168] ? __kernel_read+0x15c/0x300 [86.892185] ? kernel_read_file+0x2b1/0x320 [86.892195] init_module_from_file+0x96/0xe0 [86.892199] ? init_module_from_file+0x96/0xe0 [86.892211] idempotent_init_module+0x117/0x330 [86.892224] __x64_sys_finit_module+0x77/0x100 [86.892230] x64_sys_call+0x24de/0x2660 [86.892236] do_syscall_64+0x91/0xe90 [86.892243] ? irqentry_exit+0x77/0xb0 [86.892249] ? sysvec_apic_timer_interrupt+0x57/0xc0 [86.892256] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.892261] RIP: 0033:0x7303e1b2725d [86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48 [86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d [86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c [86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80 [86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0 [86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710 [86.892304] </TASK> Call asynchronous variant of dma_fence_work_commit() in that case. v3: Provide more verbose in-line comment (Andi), - mention target environments in commit message. Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985 Cc: Andi Shyti <[email protected]> Signed-off-by: Janusz Krzysztofik <[email protected]> Reviewed-by: Sebastian Brzezinka <[email protected]> Reviewed-by: Krzysztof Karas <[email protected]> Acked-by: Andi Shyti <[email protected]> Signed-off-by: Andi Shyti <[email protected]> Link: https://lore.kernel.org/r/[email protected] (cherry picked from commit 648ef13) Signed-off-by: Rodrigo Vivi <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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commit 9d274c1 upstream. We have been seeing crashes on duplicate keys in btrfs_set_item_key_safe(): BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192) ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.c:2620! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 gregkh#6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs] With the following stack trace: #0 btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4) #1 btrfs_drop_extents (fs/btrfs/file.c:411:4) #2 log_one_extent (fs/btrfs/tree-log.c:4732:9) #3 btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9) #4 btrfs_log_inode (fs/btrfs/tree-log.c:6626:9) #5 btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8) gregkh#6 btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8) gregkh#7 btrfs_sync_file (fs/btrfs/file.c:1933:8) gregkh#8 vfs_fsync_range (fs/sync.c:188:9) gregkh#9 vfs_fsync (fs/sync.c:202:9) gregkh#10 do_fsync (fs/sync.c:212:9) gregkh#11 __do_sys_fdatasync (fs/sync.c:225:9) gregkh#12 __se_sys_fdatasync (fs/sync.c:223:1) gregkh#13 __x64_sys_fdatasync (fs/sync.c:223:1) gregkh#14 do_syscall_x64 (arch/x86/entry/common.c:52:14) gregkh#15 do_syscall_64 (arch/x86/entry/common.c:83:7) gregkh#16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121) So we're logging a changed extent from fsync, which is splitting an extent in the log tree. But this split part already exists in the tree, triggering the BUG(). This is the state of the log tree at the time of the crash, dumped with drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py) to get more details than btrfs_print_leaf() gives us: >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"]) leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610 leaf 33439744 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160 generation 7 transid 9 size 8192 nbytes 8473563889606862198 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 204 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417704.983333333 (2024-05-22 15:41:44) mtime 1716417704.983333333 (2024-05-22 15:41:44) otime 17592186044416.000000000 (559444-03-08 01:40:16) item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13 index 195 namelen 3 name: 193 item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 4096 ram 12288 extent compression 0 (none) item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 4096 nr 8192 item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 ... So the real problem happened earlier: notice that items 4 (4k-12k) and 5 (8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and item 5 starts at i_size. Here is the state of the filesystem tree at the time of the crash: >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0)) >>> print_extent_buffer(nodes[0]) leaf 30425088 level 0 items 184 generation 9 owner 5 leaf 30425088 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da ... item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160 generation 7 transid 7 size 4096 nbytes 12288 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 6 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417703.220000000 (2024-05-22 15:41:43) mtime 1716417703.220000000 (2024-05-22 15:41:43) otime 1716417703.220000000 (2024-05-22 15:41:43) item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13 index 195 namelen 3 name: 193 item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 8192 ram 12288 extent compression 0 (none) item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 Item 5 in the log tree corresponds to item 183 in the filesystem tree, but nothing matches item 4. Furthermore, item 183 is the last item in the leaf. btrfs_log_prealloc_extents() is responsible for logging prealloc extents beyond i_size. It first truncates any previously logged prealloc extents that start beyond i_size. Then, it walks the filesystem tree and copies the prealloc extent items to the log tree. If it hits the end of a leaf, then it calls btrfs_next_leaf(), which unlocks the tree and does another search. However, while the filesystem tree is unlocked, an ordered extent completion may modify the tree. In particular, it may insert an extent item that overlaps with an extent item that was already copied to the log tree. This may manifest in several ways depending on the exact scenario, including an EEXIST error that is silently translated to a full sync, overlapping items in the log tree, or this crash. This particular crash is triggered by the following sequence of events: - Initially, the file has i_size=4k, a regular extent from 0-4k, and a prealloc extent beyond i_size from 4k-12k. The prealloc extent item is the last item in its B-tree leaf. - The file is fsync'd, which copies its inode item and both extent items to the log tree. - An xattr is set on the file, which sets the BTRFS_INODE_COPY_EVERYTHING flag. - The range 4k-8k in the file is written using direct I/O. i_size is extended to 8k, but the ordered extent is still in flight. - The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this calls copy_inode_items_to_log(), which calls btrfs_log_prealloc_extents(). - btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the filesystem tree. Since it starts before i_size, it skips it. Since it is the last item in its B-tree leaf, it calls btrfs_next_leaf(). - btrfs_next_leaf() unlocks the path. - The ordered extent completion runs, which converts the 4k-8k part of the prealloc extent to written and inserts the remaining prealloc part from 8k-12k. - btrfs_next_leaf() does a search and finds the new prealloc extent 8k-12k. - btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into the log tree. Note that it overlaps with the 4k-12k prealloc extent that was copied to the log tree by the first fsync. - fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k extent that was written. - This tries to drop the range 4k-8k in the log tree, which requires adjusting the start of the 4k-12k prealloc extent in the log tree to 8k. - btrfs_set_item_key_safe() sees that there is already an extent starting at 8k in the log tree and calls BUG(). Fix this by detecting when we're about to insert an overlapping file extent item in the log tree and truncating the part that would overlap. CC: [email protected] # 6.1+ Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Omar Sandoval <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Harshvardhan Jha <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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[ Upstream commit 38f5024 ] With CONFIG_PROVE_RCU_LIST=y and by executing $ netcat -l --sctp & $ netcat --sctp localhost & $ ss --sctp one can trigger the following Lockdep-RCU splat(s): WARNING: suspicious RCU usage 6.18.0-rc1-00093-g7f864458e9a6 #5 Not tainted ----------------------------- net/sctp/diag.c:76 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by ss/215: #0: ffff9c740828bec0 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{4:4}, at: __netlink_dump_start+0x84/0x2b0 #1: ffff9c7401d72cd0 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_sock_dump+0x38/0x200 stack backtrace: CPU: 0 UID: 0 PID: 215 Comm: ss Not tainted 6.18.0-rc1-00093-g7f864458e9a6 #5 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x5d/0x90 lockdep_rcu_suspicious.cold+0x4e/0xa3 inet_sctp_diag_fill.isra.0+0x4b1/0x5d0 sctp_sock_dump+0x131/0x200 sctp_transport_traverse_process+0x170/0x1b0 ? __pfx_sctp_sock_filter+0x10/0x10 ? __pfx_sctp_sock_dump+0x10/0x10 sctp_diag_dump+0x103/0x140 __inet_diag_dump+0x70/0xb0 netlink_dump+0x148/0x490 __netlink_dump_start+0x1f3/0x2b0 inet_diag_handler_cmd+0xcd/0x100 ? __pfx_inet_diag_dump_start+0x10/0x10 ? __pfx_inet_diag_dump+0x10/0x10 ? __pfx_inet_diag_dump_done+0x10/0x10 sock_diag_rcv_msg+0x18e/0x320 ? __pfx_sock_diag_rcv_msg+0x10/0x10 netlink_rcv_skb+0x4d/0x100 netlink_unicast+0x1d7/0x2b0 netlink_sendmsg+0x203/0x450 ____sys_sendmsg+0x30c/0x340 ___sys_sendmsg+0x94/0xf0 __sys_sendmsg+0x83/0xf0 do_syscall_64+0xbb/0x390 entry_SYSCALL_64_after_hwframe+0x77/0x7f ... </TASK> Fixes: 8f840e4 ("sctp: add the sctp_diag.c file") Signed-off-by: Stefan Wiehler <[email protected]> Reviewed-by: Kuniyuki Iwashima <[email protected]> Acked-by: Xin Long <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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[ Upstream commit 84bbe32 ] On completion of i915_vma_pin_ww(), a synchronous variant of dma_fence_work_commit() is called. When pinning a VMA to GGTT address space on a Cherry View family processor, or on a Broxton generation SoC with VTD enabled, i.e., when stop_machine() is then called from intel_ggtt_bind_vma(), that can potentially lead to lock inversion among reservation_ww and cpu_hotplug locks. [86.861179] ====================================================== [86.861193] WARNING: possible circular locking dependency detected [86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G U [86.861226] ------------------------------------------------------ [86.861238] i915_module_loa/1432 is trying to acquire lock: [86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50 [86.861290] but task is already holding lock: [86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.862233] which lock already depends on the new lock. [86.862251] the existing dependency chain (in reverse order) is: [86.862265] -> #5 (reservation_ww_class_mutex){+.+.}-{3:3}: [86.862292] dma_resv_lockdep+0x19a/0x390 [86.862315] do_one_initcall+0x60/0x3f0 [86.862334] kernel_init_freeable+0x3cd/0x680 [86.862353] kernel_init+0x1b/0x200 [86.862369] ret_from_fork+0x47/0x70 [86.862383] ret_from_fork_asm+0x1a/0x30 [86.862399] -> #4 (reservation_ww_class_acquire){+.+.}-{0:0}: [86.862425] dma_resv_lockdep+0x178/0x390 [86.862440] do_one_initcall+0x60/0x3f0 [86.862454] kernel_init_freeable+0x3cd/0x680 [86.862470] kernel_init+0x1b/0x200 [86.862482] ret_from_fork+0x47/0x70 [86.862495] ret_from_fork_asm+0x1a/0x30 [86.862509] -> #3 (&mm->mmap_lock){++++}-{3:3}: [86.862531] down_read_killable+0x46/0x1e0 [86.862546] lock_mm_and_find_vma+0xa2/0x280 [86.862561] do_user_addr_fault+0x266/0x8e0 [86.862578] exc_page_fault+0x8a/0x2f0 [86.862593] asm_exc_page_fault+0x27/0x30 [86.862607] filldir64+0xeb/0x180 [86.862620] kernfs_fop_readdir+0x118/0x480 [86.862635] iterate_dir+0xcf/0x2b0 [86.862648] __x64_sys_getdents64+0x84/0x140 [86.862661] x64_sys_call+0x1058/0x2660 [86.862675] do_syscall_64+0x91/0xe90 [86.862689] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.862703] -> #2 (&root->kernfs_rwsem){++++}-{3:3}: [86.862725] down_write+0x3e/0xf0 [86.862738] kernfs_add_one+0x30/0x3c0 [86.862751] kernfs_create_dir_ns+0x53/0xb0 [86.862765] internal_create_group+0x134/0x4c0 [86.862779] sysfs_create_group+0x13/0x20 [86.862792] topology_add_dev+0x1d/0x30 [86.862806] cpuhp_invoke_callback+0x4b5/0x850 [86.862822] cpuhp_issue_call+0xbf/0x1f0 [86.862836] __cpuhp_setup_state_cpuslocked+0x111/0x320 [86.862852] __cpuhp_setup_state+0xb0/0x220 [86.862866] topology_sysfs_init+0x30/0x50 [86.862879] do_one_initcall+0x60/0x3f0 [86.862893] kernel_init_freeable+0x3cd/0x680 [86.862908] kernel_init+0x1b/0x200 [86.862921] ret_from_fork+0x47/0x70 [86.862934] ret_from_fork_asm+0x1a/0x30 [86.862947] -> #1 (cpuhp_state_mutex){+.+.}-{3:3}: [86.862969] __mutex_lock+0xaa/0xed0 [86.862982] mutex_lock_nested+0x1b/0x30 [86.862995] __cpuhp_setup_state_cpuslocked+0x67/0x320 [86.863012] __cpuhp_setup_state+0xb0/0x220 [86.863026] page_alloc_init_cpuhp+0x2d/0x60 [86.863041] mm_core_init+0x22/0x2d0 [86.863054] start_kernel+0x576/0xbd0 [86.863068] x86_64_start_reservations+0x18/0x30 [86.863084] x86_64_start_kernel+0xbf/0x110 [86.863098] common_startup_64+0x13e/0x141 [86.863114] -> #0 (cpu_hotplug_lock){++++}-{0:0}: [86.863135] __lock_acquire+0x1635/0x2810 [86.863152] lock_acquire+0xc4/0x2f0 [86.863166] cpus_read_lock+0x41/0x100 [86.863180] stop_machine+0x1c/0x50 [86.863194] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.863987] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.864735] __vma_bind+0x55/0x70 [i915] [86.865510] fence_work+0x26/0xa0 [i915] [86.866248] fence_notify+0xa1/0x140 [i915] [86.866983] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.867719] i915_sw_fence_commit+0x39/0x60 [i915] [86.868453] i915_vma_pin_ww+0x462/0x1360 [i915] [86.869228] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.870001] initial_plane_vma+0x307/0x840 [i915] [86.870774] intel_initial_plane_config+0x33f/0x670 [i915] [86.871546] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.872330] i915_driver_probe+0x7fa/0xe80 [i915] [86.873057] i915_pci_probe+0xe6/0x220 [i915] [86.873782] local_pci_probe+0x47/0xb0 [86.873802] pci_device_probe+0xf3/0x260 [86.873817] really_probe+0xf1/0x3c0 [86.873833] __driver_probe_device+0x8c/0x180 [86.873848] driver_probe_device+0x24/0xd0 [86.873862] __driver_attach+0x10f/0x220 [86.873876] bus_for_each_dev+0x7f/0xe0 [86.873892] driver_attach+0x1e/0x30 [86.873904] bus_add_driver+0x151/0x290 [86.873917] driver_register+0x5e/0x130 [86.873931] __pci_register_driver+0x7d/0x90 [86.873945] i915_pci_register_driver+0x23/0x30 [i915] [86.874678] i915_init+0x37/0x120 [i915] [86.875347] do_one_initcall+0x60/0x3f0 [86.875369] do_init_module+0x97/0x2a0 [86.875385] load_module+0x2c54/0x2d80 [86.875398] init_module_from_file+0x96/0xe0 [86.875413] idempotent_init_module+0x117/0x330 [86.875426] __x64_sys_finit_module+0x77/0x100 [86.875440] x64_sys_call+0x24de/0x2660 [86.875454] do_syscall_64+0x91/0xe90 [86.875470] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.875486] other info that might help us debug this: [86.875502] Chain exists of: cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex [86.875539] Possible unsafe locking scenario: [86.875552] CPU0 CPU1 [86.875563] ---- ---- [86.875573] lock(reservation_ww_class_mutex); [86.875588] lock(reservation_ww_class_acquire); [86.875606] lock(reservation_ww_class_mutex); [86.875624] rlock(cpu_hotplug_lock); [86.875637] *** DEADLOCK *** [86.875650] 3 locks held by i915_module_loa/1432: [86.875663] #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220 [86.875699] #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.876512] #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915] [86.877305] stack backtrace: [86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G U 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary) [86.877334] Tainted: [U]=USER [86.877336] Hardware name: /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020 [86.877339] Call Trace: [86.877344] <TASK> [86.877353] dump_stack_lvl+0x91/0xf0 [86.877364] dump_stack+0x10/0x20 [86.877369] print_circular_bug+0x285/0x360 [86.877379] check_noncircular+0x135/0x150 [86.877390] __lock_acquire+0x1635/0x2810 [86.877403] lock_acquire+0xc4/0x2f0 [86.877408] ? stop_machine+0x1c/0x50 [86.877422] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878173] cpus_read_lock+0x41/0x100 [86.878182] ? stop_machine+0x1c/0x50 [86.878191] ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915] [86.878916] stop_machine+0x1c/0x50 [86.878927] bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915] [86.879652] intel_ggtt_bind_vma+0x43/0x70 [i915] [86.880375] __vma_bind+0x55/0x70 [i915] [86.881133] fence_work+0x26/0xa0 [i915] [86.881851] fence_notify+0xa1/0x140 [i915] [86.882566] __i915_sw_fence_complete+0x8f/0x270 [i915] [86.883286] i915_sw_fence_commit+0x39/0x60 [i915] [86.884003] i915_vma_pin_ww+0x462/0x1360 [i915] [86.884756] ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915] [86.885513] i915_vma_pin.constprop.0+0x133/0x1d0 [i915] [86.886281] initial_plane_vma+0x307/0x840 [i915] [86.887049] intel_initial_plane_config+0x33f/0x670 [i915] [86.887819] intel_display_driver_probe_nogem+0x1c6/0x260 [i915] [86.888587] i915_driver_probe+0x7fa/0xe80 [i915] [86.889293] ? mutex_unlock+0x12/0x20 [86.889301] ? drm_privacy_screen_get+0x171/0x190 [86.889308] ? acpi_dev_found+0x66/0x80 [86.889321] i915_pci_probe+0xe6/0x220 [i915] [86.890038] local_pci_probe+0x47/0xb0 [86.890049] pci_device_probe+0xf3/0x260 [86.890058] really_probe+0xf1/0x3c0 [86.890067] __driver_probe_device+0x8c/0x180 [86.890072] driver_probe_device+0x24/0xd0 [86.890078] __driver_attach+0x10f/0x220 [86.890083] ? __pfx___driver_attach+0x10/0x10 [86.890088] bus_for_each_dev+0x7f/0xe0 [86.890097] driver_attach+0x1e/0x30 [86.890101] bus_add_driver+0x151/0x290 [86.890107] driver_register+0x5e/0x130 [86.890113] __pci_register_driver+0x7d/0x90 [86.890119] i915_pci_register_driver+0x23/0x30 [i915] [86.890833] i915_init+0x37/0x120 [i915] [86.891482] ? __pfx_i915_init+0x10/0x10 [i915] [86.892135] do_one_initcall+0x60/0x3f0 [86.892145] ? __kmalloc_cache_noprof+0x33f/0x470 [86.892157] do_init_module+0x97/0x2a0 [86.892164] load_module+0x2c54/0x2d80 [86.892168] ? __kernel_read+0x15c/0x300 [86.892185] ? kernel_read_file+0x2b1/0x320 [86.892195] init_module_from_file+0x96/0xe0 [86.892199] ? init_module_from_file+0x96/0xe0 [86.892211] idempotent_init_module+0x117/0x330 [86.892224] __x64_sys_finit_module+0x77/0x100 [86.892230] x64_sys_call+0x24de/0x2660 [86.892236] do_syscall_64+0x91/0xe90 [86.892243] ? irqentry_exit+0x77/0xb0 [86.892249] ? sysvec_apic_timer_interrupt+0x57/0xc0 [86.892256] entry_SYSCALL_64_after_hwframe+0x76/0x7e [86.892261] RIP: 0033:0x7303e1b2725d [86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48 [86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d [86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c [86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80 [86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0 [86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710 [86.892304] </TASK> Call asynchronous variant of dma_fence_work_commit() in that case. v3: Provide more verbose in-line comment (Andi), - mention target environments in commit message. Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.") Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985 Cc: Andi Shyti <[email protected]> Signed-off-by: Janusz Krzysztofik <[email protected]> Reviewed-by: Sebastian Brzezinka <[email protected]> Reviewed-by: Krzysztof Karas <[email protected]> Acked-by: Andi Shyti <[email protected]> Signed-off-by: Andi Shyti <[email protected]> Link: https://lore.kernel.org/r/[email protected] (cherry picked from commit 648ef13) Signed-off-by: Rodrigo Vivi <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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… 'T'
When perf report with annotation for a symbol, press 's' and 'T', then exit
the annotate browser. Once annotate the same symbol, the annotate browser
will crash.
The browser.arch was required to be correctly updated when data type
feature was enabled by 'T'. Usually it was initialized by symbol__annotate2
function. If a symbol has already been correctly annotated at the first
time, it should not call the symbol__annotate2 function again, thus the
browser.arch will not get initialized. Then at the second time to show the
annotate browser, the data type needs to be displayed but the browser.arch
is empty.
Stack trace as below:
Perf: Segmentation fault
-------- backtrace --------
#0 0x55d365 in ui__signal_backtrace setup.c:0
#1 0x7f5ff1a3e930 in __restore_rt libc.so.6[3e930]
#2 0x570f08 in arch__is perf[570f08]
#3 0x562186 in annotate_get_insn_location perf[562186]
#4 0x562626 in __hist_entry__get_data_type annotate.c:0
#5 0x56476d in annotation_line__write perf[56476d]
gregkh#6 0x54e2db in annotate_browser__write annotate.c:0
gregkh#7 0x54d061 in ui_browser__list_head_refresh perf[54d061]
gregkh#8 0x54dc9e in annotate_browser__refresh annotate.c:0
gregkh#9 0x54c03d in __ui_browser__refresh browser.c:0
gregkh#10 0x54ccf8 in ui_browser__run perf[54ccf8]
gregkh#11 0x54eb92 in __hist_entry__tui_annotate perf[54eb92]
gregkh#12 0x552293 in do_annotate hists.c:0
gregkh#13 0x55941c in evsel__hists_browse hists.c:0
gregkh#14 0x55b00f in evlist__tui_browse_hists perf[55b00f]
gregkh#15 0x42ff02 in cmd_report perf[42ff02]
gregkh#16 0x494008 in run_builtin perf.c:0
gregkh#17 0x494305 in handle_internal_command perf.c:0
gregkh#18 0x410547 in main perf[410547]
gregkh#19 0x7f5ff1a295d0 in __libc_start_call_main libc.so.6[295d0]
gregkh#20 0x7f5ff1a29680 in __libc_start_main@@GLIBC_2.34 libc.so.6[29680]
gregkh#21 0x410b75 in _start perf[410b75]
Fixes: 1d4374a ("perf annotate: Add 'T' hot key to toggle data type display")
Reviewed-by: James Clark <[email protected]>
Tested-by: Namhyung Kim <[email protected]>
Signed-off-by: Tianyou Li <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
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When using perf record with the `--overwrite` option, a segmentation fault
occurs if an event fails to open. For example:
perf record -e cycles-ct -F 1000 -a --overwrite
Error:
cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'
perf: Segmentation fault
#0 0x6466b6 in dump_stack debug.c:366
#1 0x646729 in sighandler_dump_stack debug.c:378
#2 0x453fd1 in sigsegv_handler builtin-record.c:722
#3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090]
#4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862
#5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943
gregkh#6 0x458090 in record__synthesize builtin-record.c:2075
gregkh#7 0x45a85a in __cmd_record builtin-record.c:2888
gregkh#8 0x45deb6 in cmd_record builtin-record.c:4374
gregkh#9 0x4e5e33 in run_builtin perf.c:349
gregkh#10 0x4e60bf in handle_internal_command perf.c:401
gregkh#11 0x4e6215 in run_argv perf.c:448
gregkh#12 0x4e653a in main perf.c:555
gregkh#13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72]
gregkh#14 0x43a3ee in _start ??:0
The --overwrite option implies --tail-synthesize, which collects non-sample
events reflecting the system status when recording finishes. However, when
evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist
is not initialized and remains NULL. The code unconditionally calls
record__synthesize() in the error path, which iterates through the NULL
evlist pointer and causes a segfault.
To fix it, move the record__synthesize() call inside the error check block, so
it's only called when there was no error during recording, ensuring that evlist
is properly initialized.
Fixes: 4ea648a ("perf record: Add --tail-synthesize option")
Signed-off-by: Shuai Xue <[email protected]>
Signed-off-by: Namhyung Kim <[email protected]>
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Dec 8, 2025
When interrupting perf stat in repeat mode with a signal the signal is passed to the child process but the repeat doesn't terminate: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] ^Csleep: Interrupt [ perf stat: executing run #3 ... ] [ perf stat: executing run #4 ... ] [ perf stat: executing run #5 ... ] [ perf stat: executing run gregkh#6 ... ] [ perf stat: executing run gregkh#7 ... ] [ perf stat: executing run gregkh#8 ... ] [ perf stat: executing run gregkh#9 ... ] [ perf stat: executing run gregkh#10 ... ] Performance counter stats for 'sleep 1' (10 runs): 0.9500 +- 0.0512 seconds time elapsed ( +- 5.39% ) 0.01user 0.02system 0:09.53elapsed 0%CPU (0avgtext+0avgdata 18940maxresident)k 29944inputs+0outputs (0major+2629minor)pagefaults 0swaps ``` Terminate the repeated run and give a reasonable exit value: ``` $ perf stat -v --null --repeat 10 sleep 1 Control descriptor is not initialized [ perf stat: executing run #1 ... ] [ perf stat: executing run #2 ... ] [ perf stat: executing run #3 ... ] ^Csleep: Interrupt Performance counter stats for 'sleep 1' (10 runs): 0.680 +- 0.321 seconds time elapsed ( +- 47.16% ) Command exited with non-zero status 130 0.00user 0.01system 0:02.05elapsed 0%CPU (0avgtext+0avgdata 70688maxresident)k 0inputs+0outputs (0major+5002minor)pagefaults 0swaps ``` Note, this also changes the exit value for non-repeat runs when interrupted by a signal. Reported-by: Ingo Molnar <[email protected]> Closes: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Ian Rogers <[email protected]> Tested-by: Thomas Richter <[email protected]> Signed-off-by: Namhyung Kim <[email protected]>
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Dec 10, 2025
commit fb1a313 upstream. Function mlx5e_rep_neigh_update() wasn't updated to accommodate rtnl lock removal from TC filter update path and properly handle concurrent encap entry insertion/deletion which can lead to following use-after-free: [23827.464923] ================================================================== [23827.469446] BUG: KASAN: use-after-free in mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.470971] Read of size 4 at addr ffff8881d132228c by task kworker/u20:6/21635 [23827.472251] [23827.472615] CPU: 9 PID: 21635 Comm: kworker/u20:6 Not tainted 5.13.0-rc3+ #5 [23827.473788] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [23827.475639] Workqueue: mlx5e mlx5e_rep_neigh_update [mlx5_core] [23827.476731] Call Trace: [23827.477260] dump_stack+0xbb/0x107 [23827.477906] print_address_description.constprop.0+0x18/0x140 [23827.478896] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.479879] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.480905] kasan_report.cold+0x7c/0xd8 [23827.481701] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.482744] kasan_check_range+0x145/0x1a0 [23827.493112] mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.494054] ? mlx5e_tc_tun_encap_info_equal_generic+0x140/0x140 [mlx5_core] [23827.495296] mlx5e_rep_neigh_update+0x41e/0x5e0 [mlx5_core] [23827.496338] ? mlx5e_rep_neigh_entry_release+0xb80/0xb80 [mlx5_core] [23827.497486] ? read_word_at_a_time+0xe/0x20 [23827.498250] ? strscpy+0xa0/0x2a0 [23827.498889] process_one_work+0x8ac/0x14e0 [23827.499638] ? lockdep_hardirqs_on_prepare+0x400/0x400 [23827.500537] ? pwq_dec_nr_in_flight+0x2c0/0x2c0 [23827.501359] ? rwlock_bug.part.0+0x90/0x90 [23827.502116] worker_thread+0x53b/0x1220 [23827.502831] ? process_one_work+0x14e0/0x14e0 [23827.503627] kthread+0x328/0x3f0 [23827.504254] ? _raw_spin_unlock_irq+0x24/0x40 [23827.505065] ? __kthread_bind_mask+0x90/0x90 [23827.505912] ret_from_fork+0x1f/0x30 [23827.506621] [23827.506987] Allocated by task 28248: [23827.507694] kasan_save_stack+0x1b/0x40 [23827.508476] __kasan_kmalloc+0x7c/0x90 [23827.509197] mlx5e_attach_encap+0xde1/0x1d40 [mlx5_core] [23827.510194] mlx5e_tc_add_fdb_flow+0x397/0xc40 [mlx5_core] [23827.511218] __mlx5e_add_fdb_flow+0x519/0xb30 [mlx5_core] [23827.512234] mlx5e_configure_flower+0x191c/0x4870 [mlx5_core] [23827.513298] tc_setup_cb_add+0x1d5/0x420 [23827.514023] fl_hw_replace_filter+0x382/0x6a0 [cls_flower] [23827.514975] fl_change+0x2ceb/0x4a51 [cls_flower] [23827.515821] tc_new_tfilter+0x89a/0x2070 [23827.516548] rtnetlink_rcv_msg+0x644/0x8c0 [23827.517300] netlink_rcv_skb+0x11d/0x340 [23827.518021] netlink_unicast+0x42b/0x700 [23827.518742] netlink_sendmsg+0x743/0xc20 [23827.519467] sock_sendmsg+0xb2/0xe0 [23827.520131] ____sys_sendmsg+0x590/0x770 [23827.520851] ___sys_sendmsg+0xd8/0x160 [23827.521552] __sys_sendmsg+0xb7/0x140 [23827.522238] do_syscall_64+0x3a/0x70 [23827.522907] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.523797] [23827.524163] Freed by task 25948: [23827.524780] kasan_save_stack+0x1b/0x40 [23827.525488] kasan_set_track+0x1c/0x30 [23827.526187] kasan_set_free_info+0x20/0x30 [23827.526968] __kasan_slab_free+0xed/0x130 [23827.527709] slab_free_freelist_hook+0xcf/0x1d0 [23827.528528] kmem_cache_free_bulk+0x33a/0x6e0 [23827.529317] kfree_rcu_work+0x55f/0xb70 [23827.530024] process_one_work+0x8ac/0x14e0 [23827.530770] worker_thread+0x53b/0x1220 [23827.531480] kthread+0x328/0x3f0 [23827.532114] ret_from_fork+0x1f/0x30 [23827.532785] [23827.533147] Last potentially related work creation: [23827.534007] kasan_save_stack+0x1b/0x40 [23827.534710] kasan_record_aux_stack+0xab/0xc0 [23827.535492] kvfree_call_rcu+0x31/0x7b0 [23827.536206] mlx5e_tc_del_fdb_flow+0x577/0xef0 [mlx5_core] [23827.537305] mlx5e_flow_put+0x49/0x80 [mlx5_core] [23827.538290] mlx5e_delete_flower+0x6d1/0xe60 [mlx5_core] [23827.539300] tc_setup_cb_destroy+0x18e/0x2f0 [23827.540144] fl_hw_destroy_filter+0x1d2/0x310 [cls_flower] [23827.541148] __fl_delete+0x4dc/0x660 [cls_flower] [23827.541985] fl_delete+0x97/0x160 [cls_flower] [23827.542782] tc_del_tfilter+0x7ab/0x13d0 [23827.543503] rtnetlink_rcv_msg+0x644/0x8c0 [23827.544257] netlink_rcv_skb+0x11d/0x340 [23827.544981] netlink_unicast+0x42b/0x700 [23827.545700] netlink_sendmsg+0x743/0xc20 [23827.546424] sock_sendmsg+0xb2/0xe0 [23827.547084] ____sys_sendmsg+0x590/0x770 [23827.547850] ___sys_sendmsg+0xd8/0x160 [23827.548606] __sys_sendmsg+0xb7/0x140 [23827.549303] do_syscall_64+0x3a/0x70 [23827.549969] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.550853] [23827.551217] The buggy address belongs to the object at ffff8881d1322200 [23827.551217] which belongs to the cache kmalloc-256 of size 256 [23827.553341] The buggy address is located 140 bytes inside of [23827.553341] 256-byte region [ffff8881d1322200, ffff8881d1322300) [23827.555747] The buggy address belongs to the page: [23827.556847] page:00000000898762aa refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d1320 [23827.558651] head:00000000898762aa order:2 compound_mapcount:0 compound_pincount:0 [23827.559961] flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff) [23827.561243] raw: 002ffff800010200 dead000000000100 dead000000000122 ffff888100042b40 [23827.562653] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 [23827.564112] page dumped because: kasan: bad access detected [23827.565439] [23827.565932] Memory state around the buggy address: [23827.566917] ffff8881d1322180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.568485] ffff8881d1322200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.569818] >ffff8881d1322280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.571143] ^ [23827.571879] ffff8881d1322300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.573283] ffff8881d1322380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.574654] ================================================================== Most of the necessary logic is already correctly implemented by mlx5e_get_next_valid_encap() helper that is used in neigh stats update handler. Make the handler generic by renaming it to mlx5e_get_next_matching_encap() and use callback to test whether flow is matching instead of hardcoded check for 'valid' flag value. Implement mlx5e_get_next_valid_encap() by calling mlx5e_get_next_matching_encap() with callback that tests encap MLX5_ENCAP_ENTRY_VALID flag. Implement new mlx5e_get_next_init_encap() helper by calling mlx5e_get_next_matching_encap() with callback that tests encap completion result to be non-error and use it in mlx5e_rep_neigh_update() to safely iterate over nhe->encap_list. Remove encap completion logic from mlx5e_rep_update_flows() since the encap entries passed to this function are already guaranteed to be properly initialized by similar code in mlx5e_get_next_init_encap(). Fixes: 2a1f176 ("net/mlx5e: Refactor neigh update for concurrent execution") Signed-off-by: Vlad Buslov <[email protected]> Reviewed-by: Roi Dayan <[email protected]> Signed-off-by: Saeed Mahameed <[email protected]> Signed-off-by: Pratyush Yadav <[email protected]>
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commit fb1a313 upstream. Function mlx5e_rep_neigh_update() wasn't updated to accommodate rtnl lock removal from TC filter update path and properly handle concurrent encap entry insertion/deletion which can lead to following use-after-free: [23827.464923] ================================================================== [23827.469446] BUG: KASAN: use-after-free in mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.470971] Read of size 4 at addr ffff8881d132228c by task kworker/u20:6/21635 [23827.472251] [23827.472615] CPU: 9 PID: 21635 Comm: kworker/u20:6 Not tainted 5.13.0-rc3+ #5 [23827.473788] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [23827.475639] Workqueue: mlx5e mlx5e_rep_neigh_update [mlx5_core] [23827.476731] Call Trace: [23827.477260] dump_stack+0xbb/0x107 [23827.477906] print_address_description.constprop.0+0x18/0x140 [23827.478896] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.479879] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.480905] kasan_report.cold+0x7c/0xd8 [23827.481701] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.482744] kasan_check_range+0x145/0x1a0 [23827.493112] mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.494054] ? mlx5e_tc_tun_encap_info_equal_generic+0x140/0x140 [mlx5_core] [23827.495296] mlx5e_rep_neigh_update+0x41e/0x5e0 [mlx5_core] [23827.496338] ? mlx5e_rep_neigh_entry_release+0xb80/0xb80 [mlx5_core] [23827.497486] ? read_word_at_a_time+0xe/0x20 [23827.498250] ? strscpy+0xa0/0x2a0 [23827.498889] process_one_work+0x8ac/0x14e0 [23827.499638] ? lockdep_hardirqs_on_prepare+0x400/0x400 [23827.500537] ? pwq_dec_nr_in_flight+0x2c0/0x2c0 [23827.501359] ? rwlock_bug.part.0+0x90/0x90 [23827.502116] worker_thread+0x53b/0x1220 [23827.502831] ? process_one_work+0x14e0/0x14e0 [23827.503627] kthread+0x328/0x3f0 [23827.504254] ? _raw_spin_unlock_irq+0x24/0x40 [23827.505065] ? __kthread_bind_mask+0x90/0x90 [23827.505912] ret_from_fork+0x1f/0x30 [23827.506621] [23827.506987] Allocated by task 28248: [23827.507694] kasan_save_stack+0x1b/0x40 [23827.508476] __kasan_kmalloc+0x7c/0x90 [23827.509197] mlx5e_attach_encap+0xde1/0x1d40 [mlx5_core] [23827.510194] mlx5e_tc_add_fdb_flow+0x397/0xc40 [mlx5_core] [23827.511218] __mlx5e_add_fdb_flow+0x519/0xb30 [mlx5_core] [23827.512234] mlx5e_configure_flower+0x191c/0x4870 [mlx5_core] [23827.513298] tc_setup_cb_add+0x1d5/0x420 [23827.514023] fl_hw_replace_filter+0x382/0x6a0 [cls_flower] [23827.514975] fl_change+0x2ceb/0x4a51 [cls_flower] [23827.515821] tc_new_tfilter+0x89a/0x2070 [23827.516548] rtnetlink_rcv_msg+0x644/0x8c0 [23827.517300] netlink_rcv_skb+0x11d/0x340 [23827.518021] netlink_unicast+0x42b/0x700 [23827.518742] netlink_sendmsg+0x743/0xc20 [23827.519467] sock_sendmsg+0xb2/0xe0 [23827.520131] ____sys_sendmsg+0x590/0x770 [23827.520851] ___sys_sendmsg+0xd8/0x160 [23827.521552] __sys_sendmsg+0xb7/0x140 [23827.522238] do_syscall_64+0x3a/0x70 [23827.522907] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.523797] [23827.524163] Freed by task 25948: [23827.524780] kasan_save_stack+0x1b/0x40 [23827.525488] kasan_set_track+0x1c/0x30 [23827.526187] kasan_set_free_info+0x20/0x30 [23827.526968] __kasan_slab_free+0xed/0x130 [23827.527709] slab_free_freelist_hook+0xcf/0x1d0 [23827.528528] kmem_cache_free_bulk+0x33a/0x6e0 [23827.529317] kfree_rcu_work+0x55f/0xb70 [23827.530024] process_one_work+0x8ac/0x14e0 [23827.530770] worker_thread+0x53b/0x1220 [23827.531480] kthread+0x328/0x3f0 [23827.532114] ret_from_fork+0x1f/0x30 [23827.532785] [23827.533147] Last potentially related work creation: [23827.534007] kasan_save_stack+0x1b/0x40 [23827.534710] kasan_record_aux_stack+0xab/0xc0 [23827.535492] kvfree_call_rcu+0x31/0x7b0 [23827.536206] mlx5e_tc_del_fdb_flow+0x577/0xef0 [mlx5_core] [23827.537305] mlx5e_flow_put+0x49/0x80 [mlx5_core] [23827.538290] mlx5e_delete_flower+0x6d1/0xe60 [mlx5_core] [23827.539300] tc_setup_cb_destroy+0x18e/0x2f0 [23827.540144] fl_hw_destroy_filter+0x1d2/0x310 [cls_flower] [23827.541148] __fl_delete+0x4dc/0x660 [cls_flower] [23827.541985] fl_delete+0x97/0x160 [cls_flower] [23827.542782] tc_del_tfilter+0x7ab/0x13d0 [23827.543503] rtnetlink_rcv_msg+0x644/0x8c0 [23827.544257] netlink_rcv_skb+0x11d/0x340 [23827.544981] netlink_unicast+0x42b/0x700 [23827.545700] netlink_sendmsg+0x743/0xc20 [23827.546424] sock_sendmsg+0xb2/0xe0 [23827.547084] ____sys_sendmsg+0x590/0x770 [23827.547850] ___sys_sendmsg+0xd8/0x160 [23827.548606] __sys_sendmsg+0xb7/0x140 [23827.549303] do_syscall_64+0x3a/0x70 [23827.549969] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.550853] [23827.551217] The buggy address belongs to the object at ffff8881d1322200 [23827.551217] which belongs to the cache kmalloc-256 of size 256 [23827.553341] The buggy address is located 140 bytes inside of [23827.553341] 256-byte region [ffff8881d1322200, ffff8881d1322300) [23827.555747] The buggy address belongs to the page: [23827.556847] page:00000000898762aa refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d1320 [23827.558651] head:00000000898762aa order:2 compound_mapcount:0 compound_pincount:0 [23827.559961] flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff) [23827.561243] raw: 002ffff800010200 dead000000000100 dead000000000122 ffff888100042b40 [23827.562653] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 [23827.564112] page dumped because: kasan: bad access detected [23827.565439] [23827.565932] Memory state around the buggy address: [23827.566917] ffff8881d1322180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.568485] ffff8881d1322200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.569818] >ffff8881d1322280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.571143] ^ [23827.571879] ffff8881d1322300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.573283] ffff8881d1322380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.574654] ================================================================== Most of the necessary logic is already correctly implemented by mlx5e_get_next_valid_encap() helper that is used in neigh stats update handler. Make the handler generic by renaming it to mlx5e_get_next_matching_encap() and use callback to test whether flow is matching instead of hardcoded check for 'valid' flag value. Implement mlx5e_get_next_valid_encap() by calling mlx5e_get_next_matching_encap() with callback that tests encap MLX5_ENCAP_ENTRY_VALID flag. Implement new mlx5e_get_next_init_encap() helper by calling mlx5e_get_next_matching_encap() with callback that tests encap completion result to be non-error and use it in mlx5e_rep_neigh_update() to safely iterate over nhe->encap_list. Remove encap completion logic from mlx5e_rep_update_flows() since the encap entries passed to this function are already guaranteed to be properly initialized by similar code in mlx5e_get_next_init_encap(). Fixes: 2a1f176 ("net/mlx5e: Refactor neigh update for concurrent execution") Signed-off-by: Vlad Buslov <[email protected]> Reviewed-by: Roi Dayan <[email protected]> Signed-off-by: Saeed Mahameed <[email protected]> Signed-off-by: Pratyush Yadav <[email protected]>
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Dec 11, 2025
The one_time_gc field in struct victim_sel_policy is conditionally
initialized but unconditionally read, leading to undefined behavior
that triggers UBSAN warnings.
In f2fs_get_victim() at fs/f2fs/gc.c:774, the victim_sel_policy
structure is declared without initialization:
struct victim_sel_policy p;
The field p.one_time_gc is only assigned when the 'one_time' parameter
is true (line 789):
if (one_time) {
p.one_time_gc = one_time;
...
}
However, this field is unconditionally read in subsequent get_gc_cost()
at line 395:
if (p->one_time_gc && (valid_thresh_ratio < 100) && ...)
When one_time is false, p.one_time_gc contains uninitialized stack
memory. Hence p.one_time_gc is an invalid bool value.
UBSAN detects this invalid bool value:
UBSAN: invalid-load in fs/f2fs/gc.c:395:7
load of value 77 is not a valid value for type '_Bool'
CPU: 3 UID: 0 PID: 1297 Comm: f2fs_gc-252:16 Not tainted 6.18.0-rc3
#5 PREEMPT(voluntary)
Hardware name: OpenStack Foundation OpenStack Nova,
BIOS 1.13.0-1ubuntu1.1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x70/0x90
dump_stack+0x14/0x20
__ubsan_handle_load_invalid_value+0xb3/0xf0
? dl_server_update+0x2e/0x40
? update_curr+0x147/0x170
f2fs_get_victim.cold+0x66/0x134 [f2fs]
? sched_balance_newidle+0x2ca/0x470
? finish_task_switch.isra.0+0x8d/0x2a0
f2fs_gc+0x2ba/0x8e0 [f2fs]
? _raw_spin_unlock_irqrestore+0x12/0x40
? __timer_delete_sync+0x80/0xe0
? timer_delete_sync+0x14/0x20
? schedule_timeout+0x82/0x100
gc_thread_func+0x38b/0x860 [f2fs]
? gc_thread_func+0x38b/0x860 [f2fs]
? __pfx_autoremove_wake_function+0x10/0x10
kthread+0x10b/0x220
? __pfx_gc_thread_func+0x10/0x10 [f2fs]
? _raw_spin_unlock_irq+0x12/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork+0x11a/0x160
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
This issue is reliably reproducible with the following steps on a
100GB SSD /dev/vdb:
mkfs.f2fs -f /dev/vdb
mount /dev/vdb /mnt/f2fs_test
fio --name=gc --directory=/mnt/f2fs_test --rw=randwrite \
--bs=4k --size=8G --numjobs=12 --fsync=4 --runtime=10 \
--time_based
echo 1 > /sys/fs/f2fs/vdb/gc_urgent
The uninitialized value causes incorrect GC victim selection, leading
to unpredictable garbage collection behavior.
Fix by zero-initializing the entire victim_sel_policy structure to
ensure all fields have defined values.
Fixes: e791d00 ("f2fs: add valid block ratio not to do excessive GC for one time GC")
Cc: [email protected]
Signed-off-by: Xiaole He <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
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Dec 18, 2025
[ Upstream commit 163e5f2 ] When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 #1 0x646729 in sighandler_dump_stack debug.c:378 #2 0x453fd1 in sigsegv_handler builtin-record.c:722 #3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] #4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 #5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 gregkh#6 0x458090 in record__synthesize builtin-record.c:2075 gregkh#7 0x45a85a in __cmd_record builtin-record.c:2888 gregkh#8 0x45deb6 in cmd_record builtin-record.c:4374 gregkh#9 0x4e5e33 in run_builtin perf.c:349 gregkh#10 0x4e60bf in handle_internal_command perf.c:401 gregkh#11 0x4e6215 in run_argv perf.c:448 gregkh#12 0x4e653a in main perf.c:555 gregkh#13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] gregkh#14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648a ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Dec 18, 2025
[ Upstream commit 163e5f2 ] When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 #1 0x646729 in sighandler_dump_stack debug.c:378 #2 0x453fd1 in sigsegv_handler builtin-record.c:722 #3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] #4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 #5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 gregkh#6 0x458090 in record__synthesize builtin-record.c:2075 gregkh#7 0x45a85a in __cmd_record builtin-record.c:2888 gregkh#8 0x45deb6 in cmd_record builtin-record.c:4374 gregkh#9 0x4e5e33 in run_builtin perf.c:349 gregkh#10 0x4e60bf in handle_internal_command perf.c:401 gregkh#11 0x4e6215 in run_argv perf.c:448 gregkh#12 0x4e653a in main perf.c:555 gregkh#13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] gregkh#14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648a ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
paniakin-aws
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Dec 18, 2025
[ Upstream commit 163e5f2 ] When using perf record with the `--overwrite` option, a segmentation fault occurs if an event fails to open. For example: perf record -e cycles-ct -F 1000 -a --overwrite Error: cycles-ct:H: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat' perf: Segmentation fault #0 0x6466b6 in dump_stack debug.c:366 #1 0x646729 in sighandler_dump_stack debug.c:378 #2 0x453fd1 in sigsegv_handler builtin-record.c:722 #3 0x7f8454e65090 in __restore_rt libc-2.32.so[54090] #4 0x6c5671 in __perf_event__synthesize_id_index synthetic-events.c:1862 #5 0x6c5ac0 in perf_event__synthesize_id_index synthetic-events.c:1943 gregkh#6 0x458090 in record__synthesize builtin-record.c:2075 gregkh#7 0x45a85a in __cmd_record builtin-record.c:2888 gregkh#8 0x45deb6 in cmd_record builtin-record.c:4374 gregkh#9 0x4e5e33 in run_builtin perf.c:349 gregkh#10 0x4e60bf in handle_internal_command perf.c:401 gregkh#11 0x4e6215 in run_argv perf.c:448 gregkh#12 0x4e653a in main perf.c:555 gregkh#13 0x7f8454e4fa72 in __libc_start_main libc-2.32.so[3ea72] gregkh#14 0x43a3ee in _start ??:0 The --overwrite option implies --tail-synthesize, which collects non-sample events reflecting the system status when recording finishes. However, when evsel opening fails (e.g., unsupported event 'cycles-ct'), session->evlist is not initialized and remains NULL. The code unconditionally calls record__synthesize() in the error path, which iterates through the NULL evlist pointer and causes a segfault. To fix it, move the record__synthesize() call inside the error check block, so it's only called when there was no error during recording, ensuring that evlist is properly initialized. Fixes: 4ea648a ("perf record: Add --tail-synthesize option") Signed-off-by: Shuai Xue <[email protected]> Signed-off-by: Namhyung Kim <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Dec 18, 2025
commit fb1a313 upstream. Function mlx5e_rep_neigh_update() wasn't updated to accommodate rtnl lock removal from TC filter update path and properly handle concurrent encap entry insertion/deletion which can lead to following use-after-free: [23827.464923] ================================================================== [23827.469446] BUG: KASAN: use-after-free in mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.470971] Read of size 4 at addr ffff8881d132228c by task kworker/u20:6/21635 [23827.472251] [23827.472615] CPU: 9 PID: 21635 Comm: kworker/u20:6 Not tainted 5.13.0-rc3+ #5 [23827.473788] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [23827.475639] Workqueue: mlx5e mlx5e_rep_neigh_update [mlx5_core] [23827.476731] Call Trace: [23827.477260] dump_stack+0xbb/0x107 [23827.477906] print_address_description.constprop.0+0x18/0x140 [23827.478896] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.479879] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.480905] kasan_report.cold+0x7c/0xd8 [23827.481701] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.482744] kasan_check_range+0x145/0x1a0 [23827.493112] mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.494054] ? mlx5e_tc_tun_encap_info_equal_generic+0x140/0x140 [mlx5_core] [23827.495296] mlx5e_rep_neigh_update+0x41e/0x5e0 [mlx5_core] [23827.496338] ? mlx5e_rep_neigh_entry_release+0xb80/0xb80 [mlx5_core] [23827.497486] ? read_word_at_a_time+0xe/0x20 [23827.498250] ? strscpy+0xa0/0x2a0 [23827.498889] process_one_work+0x8ac/0x14e0 [23827.499638] ? lockdep_hardirqs_on_prepare+0x400/0x400 [23827.500537] ? pwq_dec_nr_in_flight+0x2c0/0x2c0 [23827.501359] ? rwlock_bug.part.0+0x90/0x90 [23827.502116] worker_thread+0x53b/0x1220 [23827.502831] ? process_one_work+0x14e0/0x14e0 [23827.503627] kthread+0x328/0x3f0 [23827.504254] ? _raw_spin_unlock_irq+0x24/0x40 [23827.505065] ? __kthread_bind_mask+0x90/0x90 [23827.505912] ret_from_fork+0x1f/0x30 [23827.506621] [23827.506987] Allocated by task 28248: [23827.507694] kasan_save_stack+0x1b/0x40 [23827.508476] __kasan_kmalloc+0x7c/0x90 [23827.509197] mlx5e_attach_encap+0xde1/0x1d40 [mlx5_core] [23827.510194] mlx5e_tc_add_fdb_flow+0x397/0xc40 [mlx5_core] [23827.511218] __mlx5e_add_fdb_flow+0x519/0xb30 [mlx5_core] [23827.512234] mlx5e_configure_flower+0x191c/0x4870 [mlx5_core] [23827.513298] tc_setup_cb_add+0x1d5/0x420 [23827.514023] fl_hw_replace_filter+0x382/0x6a0 [cls_flower] [23827.514975] fl_change+0x2ceb/0x4a51 [cls_flower] [23827.515821] tc_new_tfilter+0x89a/0x2070 [23827.516548] rtnetlink_rcv_msg+0x644/0x8c0 [23827.517300] netlink_rcv_skb+0x11d/0x340 [23827.518021] netlink_unicast+0x42b/0x700 [23827.518742] netlink_sendmsg+0x743/0xc20 [23827.519467] sock_sendmsg+0xb2/0xe0 [23827.520131] ____sys_sendmsg+0x590/0x770 [23827.520851] ___sys_sendmsg+0xd8/0x160 [23827.521552] __sys_sendmsg+0xb7/0x140 [23827.522238] do_syscall_64+0x3a/0x70 [23827.522907] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.523797] [23827.524163] Freed by task 25948: [23827.524780] kasan_save_stack+0x1b/0x40 [23827.525488] kasan_set_track+0x1c/0x30 [23827.526187] kasan_set_free_info+0x20/0x30 [23827.526968] __kasan_slab_free+0xed/0x130 [23827.527709] slab_free_freelist_hook+0xcf/0x1d0 [23827.528528] kmem_cache_free_bulk+0x33a/0x6e0 [23827.529317] kfree_rcu_work+0x55f/0xb70 [23827.530024] process_one_work+0x8ac/0x14e0 [23827.530770] worker_thread+0x53b/0x1220 [23827.531480] kthread+0x328/0x3f0 [23827.532114] ret_from_fork+0x1f/0x30 [23827.532785] [23827.533147] Last potentially related work creation: [23827.534007] kasan_save_stack+0x1b/0x40 [23827.534710] kasan_record_aux_stack+0xab/0xc0 [23827.535492] kvfree_call_rcu+0x31/0x7b0 [23827.536206] mlx5e_tc_del_fdb_flow+0x577/0xef0 [mlx5_core] [23827.537305] mlx5e_flow_put+0x49/0x80 [mlx5_core] [23827.538290] mlx5e_delete_flower+0x6d1/0xe60 [mlx5_core] [23827.539300] tc_setup_cb_destroy+0x18e/0x2f0 [23827.540144] fl_hw_destroy_filter+0x1d2/0x310 [cls_flower] [23827.541148] __fl_delete+0x4dc/0x660 [cls_flower] [23827.541985] fl_delete+0x97/0x160 [cls_flower] [23827.542782] tc_del_tfilter+0x7ab/0x13d0 [23827.543503] rtnetlink_rcv_msg+0x644/0x8c0 [23827.544257] netlink_rcv_skb+0x11d/0x340 [23827.544981] netlink_unicast+0x42b/0x700 [23827.545700] netlink_sendmsg+0x743/0xc20 [23827.546424] sock_sendmsg+0xb2/0xe0 [23827.547084] ____sys_sendmsg+0x590/0x770 [23827.547850] ___sys_sendmsg+0xd8/0x160 [23827.548606] __sys_sendmsg+0xb7/0x140 [23827.549303] do_syscall_64+0x3a/0x70 [23827.549969] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.550853] [23827.551217] The buggy address belongs to the object at ffff8881d1322200 [23827.551217] which belongs to the cache kmalloc-256 of size 256 [23827.553341] The buggy address is located 140 bytes inside of [23827.553341] 256-byte region [ffff8881d1322200, ffff8881d1322300) [23827.555747] The buggy address belongs to the page: [23827.556847] page:00000000898762aa refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d1320 [23827.558651] head:00000000898762aa order:2 compound_mapcount:0 compound_pincount:0 [23827.559961] flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff) [23827.561243] raw: 002ffff800010200 dead000000000100 dead000000000122 ffff888100042b40 [23827.562653] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 [23827.564112] page dumped because: kasan: bad access detected [23827.565439] [23827.565932] Memory state around the buggy address: [23827.566917] ffff8881d1322180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.568485] ffff8881d1322200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.569818] >ffff8881d1322280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.571143] ^ [23827.571879] ffff8881d1322300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.573283] ffff8881d1322380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.574654] ================================================================== Most of the necessary logic is already correctly implemented by mlx5e_get_next_valid_encap() helper that is used in neigh stats update handler. Make the handler generic by renaming it to mlx5e_get_next_matching_encap() and use callback to test whether flow is matching instead of hardcoded check for 'valid' flag value. Implement mlx5e_get_next_valid_encap() by calling mlx5e_get_next_matching_encap() with callback that tests encap MLX5_ENCAP_ENTRY_VALID flag. Implement new mlx5e_get_next_init_encap() helper by calling mlx5e_get_next_matching_encap() with callback that tests encap completion result to be non-error and use it in mlx5e_rep_neigh_update() to safely iterate over nhe->encap_list. Remove encap completion logic from mlx5e_rep_update_flows() since the encap entries passed to this function are already guaranteed to be properly initialized by similar code in mlx5e_get_next_init_encap(). Fixes: 2a1f176 ("net/mlx5e: Refactor neigh update for concurrent execution") Signed-off-by: Vlad Buslov <[email protected]> Reviewed-by: Roi Dayan <[email protected]> Signed-off-by: Saeed Mahameed <[email protected]> Signed-off-by: Pratyush Yadav <[email protected]>
paniakin-aws
pushed a commit
that referenced
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Dec 18, 2025
commit fb1a313 upstream. Function mlx5e_rep_neigh_update() wasn't updated to accommodate rtnl lock removal from TC filter update path and properly handle concurrent encap entry insertion/deletion which can lead to following use-after-free: [23827.464923] ================================================================== [23827.469446] BUG: KASAN: use-after-free in mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.470971] Read of size 4 at addr ffff8881d132228c by task kworker/u20:6/21635 [23827.472251] [23827.472615] CPU: 9 PID: 21635 Comm: kworker/u20:6 Not tainted 5.13.0-rc3+ #5 [23827.473788] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [23827.475639] Workqueue: mlx5e mlx5e_rep_neigh_update [mlx5_core] [23827.476731] Call Trace: [23827.477260] dump_stack+0xbb/0x107 [23827.477906] print_address_description.constprop.0+0x18/0x140 [23827.478896] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.479879] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.480905] kasan_report.cold+0x7c/0xd8 [23827.481701] ? mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.482744] kasan_check_range+0x145/0x1a0 [23827.493112] mlx5e_encap_take+0x72/0x140 [mlx5_core] [23827.494054] ? mlx5e_tc_tun_encap_info_equal_generic+0x140/0x140 [mlx5_core] [23827.495296] mlx5e_rep_neigh_update+0x41e/0x5e0 [mlx5_core] [23827.496338] ? mlx5e_rep_neigh_entry_release+0xb80/0xb80 [mlx5_core] [23827.497486] ? read_word_at_a_time+0xe/0x20 [23827.498250] ? strscpy+0xa0/0x2a0 [23827.498889] process_one_work+0x8ac/0x14e0 [23827.499638] ? lockdep_hardirqs_on_prepare+0x400/0x400 [23827.500537] ? pwq_dec_nr_in_flight+0x2c0/0x2c0 [23827.501359] ? rwlock_bug.part.0+0x90/0x90 [23827.502116] worker_thread+0x53b/0x1220 [23827.502831] ? process_one_work+0x14e0/0x14e0 [23827.503627] kthread+0x328/0x3f0 [23827.504254] ? _raw_spin_unlock_irq+0x24/0x40 [23827.505065] ? __kthread_bind_mask+0x90/0x90 [23827.505912] ret_from_fork+0x1f/0x30 [23827.506621] [23827.506987] Allocated by task 28248: [23827.507694] kasan_save_stack+0x1b/0x40 [23827.508476] __kasan_kmalloc+0x7c/0x90 [23827.509197] mlx5e_attach_encap+0xde1/0x1d40 [mlx5_core] [23827.510194] mlx5e_tc_add_fdb_flow+0x397/0xc40 [mlx5_core] [23827.511218] __mlx5e_add_fdb_flow+0x519/0xb30 [mlx5_core] [23827.512234] mlx5e_configure_flower+0x191c/0x4870 [mlx5_core] [23827.513298] tc_setup_cb_add+0x1d5/0x420 [23827.514023] fl_hw_replace_filter+0x382/0x6a0 [cls_flower] [23827.514975] fl_change+0x2ceb/0x4a51 [cls_flower] [23827.515821] tc_new_tfilter+0x89a/0x2070 [23827.516548] rtnetlink_rcv_msg+0x644/0x8c0 [23827.517300] netlink_rcv_skb+0x11d/0x340 [23827.518021] netlink_unicast+0x42b/0x700 [23827.518742] netlink_sendmsg+0x743/0xc20 [23827.519467] sock_sendmsg+0xb2/0xe0 [23827.520131] ____sys_sendmsg+0x590/0x770 [23827.520851] ___sys_sendmsg+0xd8/0x160 [23827.521552] __sys_sendmsg+0xb7/0x140 [23827.522238] do_syscall_64+0x3a/0x70 [23827.522907] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.523797] [23827.524163] Freed by task 25948: [23827.524780] kasan_save_stack+0x1b/0x40 [23827.525488] kasan_set_track+0x1c/0x30 [23827.526187] kasan_set_free_info+0x20/0x30 [23827.526968] __kasan_slab_free+0xed/0x130 [23827.527709] slab_free_freelist_hook+0xcf/0x1d0 [23827.528528] kmem_cache_free_bulk+0x33a/0x6e0 [23827.529317] kfree_rcu_work+0x55f/0xb70 [23827.530024] process_one_work+0x8ac/0x14e0 [23827.530770] worker_thread+0x53b/0x1220 [23827.531480] kthread+0x328/0x3f0 [23827.532114] ret_from_fork+0x1f/0x30 [23827.532785] [23827.533147] Last potentially related work creation: [23827.534007] kasan_save_stack+0x1b/0x40 [23827.534710] kasan_record_aux_stack+0xab/0xc0 [23827.535492] kvfree_call_rcu+0x31/0x7b0 [23827.536206] mlx5e_tc_del_fdb_flow+0x577/0xef0 [mlx5_core] [23827.537305] mlx5e_flow_put+0x49/0x80 [mlx5_core] [23827.538290] mlx5e_delete_flower+0x6d1/0xe60 [mlx5_core] [23827.539300] tc_setup_cb_destroy+0x18e/0x2f0 [23827.540144] fl_hw_destroy_filter+0x1d2/0x310 [cls_flower] [23827.541148] __fl_delete+0x4dc/0x660 [cls_flower] [23827.541985] fl_delete+0x97/0x160 [cls_flower] [23827.542782] tc_del_tfilter+0x7ab/0x13d0 [23827.543503] rtnetlink_rcv_msg+0x644/0x8c0 [23827.544257] netlink_rcv_skb+0x11d/0x340 [23827.544981] netlink_unicast+0x42b/0x700 [23827.545700] netlink_sendmsg+0x743/0xc20 [23827.546424] sock_sendmsg+0xb2/0xe0 [23827.547084] ____sys_sendmsg+0x590/0x770 [23827.547850] ___sys_sendmsg+0xd8/0x160 [23827.548606] __sys_sendmsg+0xb7/0x140 [23827.549303] do_syscall_64+0x3a/0x70 [23827.549969] entry_SYSCALL_64_after_hwframe+0x44/0xae [23827.550853] [23827.551217] The buggy address belongs to the object at ffff8881d1322200 [23827.551217] which belongs to the cache kmalloc-256 of size 256 [23827.553341] The buggy address is located 140 bytes inside of [23827.553341] 256-byte region [ffff8881d1322200, ffff8881d1322300) [23827.555747] The buggy address belongs to the page: [23827.556847] page:00000000898762aa refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1d1320 [23827.558651] head:00000000898762aa order:2 compound_mapcount:0 compound_pincount:0 [23827.559961] flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff) [23827.561243] raw: 002ffff800010200 dead000000000100 dead000000000122 ffff888100042b40 [23827.562653] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 [23827.564112] page dumped because: kasan: bad access detected [23827.565439] [23827.565932] Memory state around the buggy address: [23827.566917] ffff8881d1322180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.568485] ffff8881d1322200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.569818] >ffff8881d1322280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [23827.571143] ^ [23827.571879] ffff8881d1322300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.573283] ffff8881d1322380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [23827.574654] ================================================================== Most of the necessary logic is already correctly implemented by mlx5e_get_next_valid_encap() helper that is used in neigh stats update handler. Make the handler generic by renaming it to mlx5e_get_next_matching_encap() and use callback to test whether flow is matching instead of hardcoded check for 'valid' flag value. Implement mlx5e_get_next_valid_encap() by calling mlx5e_get_next_matching_encap() with callback that tests encap MLX5_ENCAP_ENTRY_VALID flag. Implement new mlx5e_get_next_init_encap() helper by calling mlx5e_get_next_matching_encap() with callback that tests encap completion result to be non-error and use it in mlx5e_rep_neigh_update() to safely iterate over nhe->encap_list. Remove encap completion logic from mlx5e_rep_update_flows() since the encap entries passed to this function are already guaranteed to be properly initialized by similar code in mlx5e_get_next_init_encap(). Fixes: 2a1f176 ("net/mlx5e: Refactor neigh update for concurrent execution") Signed-off-by: Vlad Buslov <[email protected]> Reviewed-by: Roi Dayan <[email protected]> Signed-off-by: Saeed Mahameed <[email protected]> Signed-off-by: Pratyush Yadav <[email protected]>
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On systems with memory overcommit, although no more pages will be removed without the consent of virtio-balloon, not all pages are guaranteed to be present at boot time. They need to be faulted in when mapped for DMA.
Enable this by default for the relevant EC2 instance types to avoid a lot of time wasted in building separate images with the command line option.
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