On 9/6/23 09:12, Albert Esteve wrote: > > > On Thu, Aug 31, 2023 at 9:14 AM Laszlo Ersek <ler...@redhat.com > <mailto:ler...@redhat.com>> wrote: > > On 8/30/23 15:40, Laszlo Ersek wrote: > > Cc: "Michael S. Tsirkin" <m...@redhat.com <mailto:m...@redhat.com>> > (supporter:vhost) > > Cc: Eugenio Perez Martin <epere...@redhat.com > <mailto:epere...@redhat.com>> > > Cc: German Maglione <gmagli...@redhat.com > <mailto:gmagli...@redhat.com>> > > Cc: Liu Jiang <ge...@linux.alibaba.com > <mailto:ge...@linux.alibaba.com>> > > Cc: Sergio Lopez Pascual <s...@redhat.com <mailto:s...@redhat.com>> > > Cc: Stefano Garzarella <sgarz...@redhat.com > <mailto:sgarz...@redhat.com>> > > Signed-off-by: Laszlo Ersek <ler...@redhat.com > <mailto:ler...@redhat.com>> > > Reviewed-by: Stefano Garzarella <sgarz...@redhat.com > <mailto:sgarz...@redhat.com>> > > --- > > > > Notes: > > v2: > > > > - pick up Stefano's R-b > > > > hw/virtio/vhost-user.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > This has been > > Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org > <mailto:phi...@linaro.org>> > > under the (identical) v1 posting: > > > http://mid.mail-archive.com/cd0604a1-6826-ac6c-6c47-dcb6def64b28@linaro.org > <http://mid.mail-archive.com/cd0604a1-6826-ac6c-6c47-dcb6def64b28@linaro.org> > > Thanks, Phil! (and sorry that I posted v2 too quickly -- I forgot that > sometimes reviewers split a review over multiple days.) > > Laszlo > > > > > diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c > > index 8dcf049d422b..b4b677c1ce66 100644 > > --- a/hw/virtio/vhost-user.c > > +++ b/hw/virtio/vhost-user.c > > @@ -398,7 +398,7 @@ static int vhost_user_write(struct vhost_dev > *dev, VhostUserMsg *msg, > > * operations such as configuring device memory mappings or > issuing device > > * resets, which affect the whole device instead of > individual VQs, > > * vhost-user messages should only be sent once. > > - * > > + * > > * Devices with multiple vhost_devs are given an associated > dev->vq_index > > * so per_device requests are only sent if vq_index is 0. > > */ > > > > > Thanks for the series! > I had a timeout problem with a virtio device I am developing, and I was > not sure yet what was going on. > Your description of the problem seemed to fit mine, in my case the > driver sent a command through the data plane > right after the feature negotiation that reached the backend too soon. > Adding delays alleviated the issue, so it > already hinted me to a race condition. > > I tested using this patch series and according to my experiments, it > really lowers the chances to get the deadlock. > Sadly, I do still get the issue sometimes, though (not frequently)... > However, I think probably the solution comes not > from the Qemu side, but from the rust-vmm vhost-user-backend crate. I am > looking for that solution on my side. > > But that does not invalidate this patch, which I think is a necessary > improvement, and in my tests it really > helps a lot with the described issue. Therefore: > > Tested-by: Albert Esteve <aest...@redhat.com <mailto:aest...@redhat.com>>
Thanks again -- I'm picking this up for the whole series. Laszlo > > BR, > Albert
