On Mon, 8 May 2023 11:09:46 +0200, Eugenio Perez Martin <epere...@redhat.com> wrote: > On Sat, May 6, 2023 at 4:25 AM Xuan Zhuo <xuanz...@linux.alibaba.com> wrote: > > > > On Thu, 4 May 2023 12:14:47 +0200, =?utf-8?q?Eugenio_P=C3=A9rez?= > > <epere...@redhat.com> wrote: > > > The commit 93a97dc5200a ("virtio-net: enable vq reset feature") enables > > > unconditionally vq reset feature as long as the device is emulated. > > > This makes impossible to actually disable the feature, and it causes > > > migration problems from qemu version previous than 7.2. > > > > > > The entire final commit is unneeded as device system already enable or > > > disable the feature properly. > > > > > > This reverts commit 93a97dc5200a95e63b99cb625f20b7ae802ba413. > > > Fixes: 93a97dc5200a ("virtio-net: enable vq reset feature") > > > Signed-off-by: Eugenio Pérez <epere...@redhat.com> > > > > > > --- > > > Tested by checking feature bit at /sys/devices/pci.../virtio0/features > > > enabling and disabling queue_reset virtio-net feature and vhost=on/off > > > on net device backend. > > > > Do you mean that this feature cannot be closed? > > > > I tried to close in the guest, it was successful. > > > > I'm not sure what you mean with close. If the device dataplane is > emulated in qemu (vhost=off), I'm not able to make the device not > offer it. > > > In addition, in this case, could you try to repair the problem instead of > > directly revert. > > > > I'm not following this. The revert is not to always disable the feature. > > By default, the feature is enabled. If cmdline states queue_reset=on, > the feature is enabled. That is true both before and after applying > this patch. > > However, in qemu master, queue_reset=off keeps enabling this feature > on the device. It happens that there is a commit explicitly doing > that, so I'm reverting it. > > Let me know if that makes sense to you.
I got it. Looks like it's indeed a bug. Reviewed-by: Xuan Zhuo <xuanz...@linux.alibaba.com> Thanks. > > Thanks! >