Re: [PATCH v2 0/2] virtio-balloon: make it spec compliant

From: Michael S. Tsirkin
Date: Wed Jul 10 2024 - 14:42:03 EST


On Wed, Jul 10, 2024 at 08:25:56PM +0200, David Hildenbrand wrote:
> On 10.07.24 13:42, 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 qemu virtio pci driver
> > is *also* out of spec.
> >
> > To fix:
> > 1. add vq4 as per spec
> > 2. to help out the buggy qemu driver, if finding vqs fail,
> > try with vq3 as reporting.
> >
> > Fixes: b0c504f15471 ("virtio-balloon: add support for providing free page reports to host")
> > Cc: "Alexander Duyck" <alexander.h.duyck@xxxxxxxxxxxxxxx>
> > Reported-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
> > Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> >
> > Changes from v1:
> > rebased on vhost tip
> >
>
> Looks like you missed to include acks from me and Jason.
>
> --
> Cheers,
>
> David / dhildenb


indeed they are on lore but not in the mbox, weird. fixed - thanks
for pointing this out.