On 04.07.24 23:30, Michael S. Tsirkin wrote:
Currently, if VIRTIO_BALLOON_F_FREE_PAGE_HINT is off but VIRTIO_BALLOON_F_REPORTING is on, then the reporting vq gets number 3 while spec says it's number 4. It happens to work because the linux virtio pci driver is *also* out of spec.To fix: 1. add vq4 as per spec 2. to help out the buggy Linux driver, in the above configuration, also create vq3, and handle it exactly as we do vq4. I think that some clever hack is doable to address the issue for existing machine types (which would get it in user's hands sooner), but I'm not 100% sure what, exactly. This is a simpler, straight-forward approach. Reported-by: Xuan Zhuo <[email protected]> Signed-off-by: Michael S. Tsirkin <[email protected]> --- I don't think I'll stop here, I want to fix exiting machine types, but sending this here for comparison. I'll send a Linux patch later.
The downside is that new machine types will stop working with mainline Linux / major distros in that feature combination, right?
What's the approach that you are thinking of? -- Cheers, David / dhildenb
