Hi,

I applied patch from:
https://www.spinics.net/lists//devicetree/msg694496.html

For now only compilation is tested as we don't have anything to test it
on yet.

For the test we were using EVB that has SPI eeprom on board. Here are
dts nodes I added to the IPQ dts:
```
spi_bridge0: spi@28 {
			compatible = "nxp,sc18is606";
			reg = <0x28>;

		eeprom@1 {
			/* EVB manual says to use SS1 as CS */
			reg = <1>;

			compatible = "atmel,at25";
			address-width = <8>;
			size = <128>;
			pagesize = <8>;

			spi-max-frequency = <1875000>;

			/* EVB datasheet says to use SPI mode 3, so cpol and cpha are 1 */

			spi-cpol;
			spi-cpha;
			};
		};
```

And then to test write/read to eeprom used:
```
echo "test" > /sys/class/spi_master/spi1/spi1.1/eeprom
cat /sys/class/spi_master/spi1/spi1.1/eeprom
```

Hi,

I applied patch from:
https://www.spinics.net/lists//devicetree/msg694496.html

For now only compilation is tested as we don't have anything to test it
on yet.

For the test we were using EVB that has SPI eeprom on board. Here are
dts nodes I added to the IPQ dts:
```
spi_bridge0: spi@28 {
			compatible = "nxp,sc18is606";
			reg = <0x28>;

		eeprom@1 {
			/* EVB manual says to use SS1 as CS */
			reg = <1>;

			compatible = "atmel,at25";
			address-width = <8>;
			size = <128>;
			pagesize = <8>;

			spi-max-frequency = <1875000>;

			/* EVB datasheet says to use SPI mode 3, so cpol and cpha are 1 */

			spi-cpol;
			spi-cpha;
			};
		};
```

And then to test write/read to eeprom used:
```
echo "test" > /sys/class/spi_master/spi1/spi1.1/eeprom
cat /sys/class/spi_master/spi1/spi1.1/eeprom
```

The following lockdep splat was observed while kernel auto-online a CXL
memory region:

======================================================
WARNING: possible circular locking dependency detected
6.17.0djtest+ #53 Tainted: G        W
------------------------------------------------------
systemd-udevd/3334 is trying to acquire lock:
ffffffff90346188 (hmem_resource_lock){+.+.}-{4:4}, at: hmem_register_resource+0x31/0x50

but task is already holding lock:
ffffffff90338890 ((node_chain).rwsem){++++}-{4:4}, at: blocking_notifier_call_chain+0x2e/0x70

which lock already depends on the new lock.
[..]
Chain exists of:
  hmem_resource_lock --> mem_hotplug_lock --> (node_chain).rwsem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock((node_chain).rwsem);
                               lock(mem_hotplug_lock);
                               lock((node_chain).rwsem);
  lock(hmem_resource_lock);

The lock ordering can cause potential deadlock. There are instances
where hmem_resource_lock is taken after (node_chain).rwsem, and vice
versa.

Split out the target update section of hmat_register_target() so that
hmat_callback() only envokes that section instead of attempt to register
hmem devices that it does not need to.

[ dj: Fix up comment to be closer to 80cols. (Jonathan) ]

Fixes: cf8741a ("ACPI: NUMA: HMAT: Register "soft reserved" memory as an "hmem" device")
Reviewed-by: Jonathan Cameron <[email protected]>
Tested-by: Smita Koralahalli <[email protected]>
Reviewed-by: Smita Koralahalli <[email protected]>
Reviewed-by: Dan Williams <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Dave Jiang <[email protected]>

Hi,

I applied patch from:
https://www.spinics.net/lists//devicetree/msg694496.html

For now only compilation is tested as we don't have anything to test it
on yet.

For the test we were using EVB that has SPI eeprom on board. Here are
dts nodes I added to the IPQ dts:
```
spi_bridge0: spi@28 {
			compatible = "nxp,sc18is606";
			reg = <0x28>;

		eeprom@1 {
			/* EVB manual says to use SS1 as CS */
			reg = <1>;

			compatible = "atmel,at25";
			address-width = <8>;
			size = <128>;
			pagesize = <8>;

			spi-max-frequency = <1875000>;

			/* EVB datasheet says to use SPI mode 3, so cpol and cpha are 1 */

			spi-cpol;
			spi-cpha;
			};
		};
```

And then to test write/read to eeprom used:
```
echo "test" > /sys/class/spi_master/spi1/spi1.1/eeprom
cat /sys/class/spi_master/spi1/spi1.1/eeprom
```

Hi,

I applied patch from:
https://www.spinics.net/lists//devicetree/msg694496.html

For now only compilation is tested as we don't have anything to test it
on yet.

For the test we were using EVB that has SPI eeprom on board. Here are
dts nodes I added to the IPQ dts:
```
spi_bridge0: spi@28 {
			compatible = "nxp,sc18is606";
			reg = <0x28>;

		eeprom@1 {
			/* EVB manual says to use SS1 as CS */
			reg = <1>;

			compatible = "atmel,at25";
			address-width = <8>;
			size = <128>;
			pagesize = <8>;

			spi-max-frequency = <1875000>;

			/* EVB datasheet says to use SPI mode 3, so cpol and cpha are 1 */

			spi-cpol;
			spi-cpha;
			};
		};
```

And then to test write/read to eeprom used:
```
echo "test" > /sys/class/spi_master/spi1/spi1.1/eeprom
cat /sys/class/spi_master/spi1/spi1.1/eeprom
```