Noisy virtio-pci ack_features warning on newer kernels #7414
Description
Since mainline linux commit torvalds/linux@69b9461, virtio pci can set all 128 feature bits, but cloud-hypervisor warns noisily when there are more than two 32-bit words in write_common_config_dword():
cloud-hypervisor/virtio-devices/src/transport/pci_common_config.rs
Lines 329 to 338 in bb9d352
Symptoms look like
cloud-hypervisor: 134.138928ms: <vcpu0> WARN:virtio-devices/src/transport/pci_common_config.rs:334 -- invalid ack_features (page 2, value 0x0)
cloud-hypervisor: 134.179294ms: <vcpu0> WARN:virtio-devices/src/transport/pci_common_config.rs:334 -- invalid ack_features (page 3, value 0x0)
cloud-hypervisor: 138.168374ms: <vcpu0> WARN:virtio-devices/src/transport/pci_common_config.rs:334 -- invalid ack_features (page 2, value 0x0)
cloud-hypervisor: 138.208690ms: <vcpu0> WARN:virtio-devices/src/transport/pci_common_config.rs:334 -- invalid ack_features (page 3, value 0x0)
on startup and occur on any mainline kernel after that commit, including the release 6.17 and stable 6.17.x kernels.