Virtualization - Jun 2021 - virtio-net: kernel panic in virtio_net.c

On Wed, 9 Jun 2021 08:24:20 +0200, Greg KH <gregkh at linuxfoundation.org>
wrote:
> On Wed, Jun 09, 2021 at 02:08:17PM +0800, Xuan Zhuo wrote:
> > On Wed, 9 Jun 2021 06:50:10 +0200, Greg KH <gregkh at
linuxfoundation.org> wrote:
> > > On Wed, Jun 09, 2021 at 09:48:33AM +0800, Xuan Zhuo wrote:
> > > > > > With this patch and the latest net branch I no
longer get crashes.
> > > > >
> > > > > Did this ever get properly submitted to the networking
tree to get into
> > > > > 5.13-final?
> > > >
> > > > The patch has been submitted.
> > > >
> > > > 	[PATCH net] virtio-net: fix for skb_over_panic inside big
mode
> > >
> > > Submitted where?  Do you have a lore.kernel.org link somewhere?
> >
> >
> > https://lore.kernel.org/netdev/20210603170901.66504-1-xuanzhuo at
linux.alibaba.com/
>
> So this is commit 1a8024239dac ("virtio-net: fix for skb_over_panic
> inside big mode") in Linus's tree, right?
YES.
>
> But why is that referencing:
> 	Fixes: fb32856b16ad ("virtio-net: page_to_skb() use build_skb when
there's sufficient tailroom")
This problem was indeed introduced in fb32856b16ad.

I confirmed that this commit fb32856b16ad was first entered in 5.13-rc1, and the
previous 5.12 did not have this commit fb32856b16ad.

I'm not sure if it helped you.

Thanks.
>
> when this problem was seen in stable kernels that had a different commit
> backported to it?
>
> Is there nothing needed to be done for the stable kernel trees?
>
> confused,
>
> greg k-h

On Wed, Jun 09, 2021 at 03:51:20PM +0800, Xuan Zhuo
wrote:
> On Wed, 9 Jun 2021 08:24:20 +0200, Greg KH <gregkh at
linuxfoundation.org> wrote:
> > On Wed, Jun 09, 2021 at 02:08:17PM +0800, Xuan Zhuo wrote:
> > > On Wed, 9 Jun 2021 06:50:10 +0200, Greg KH <gregkh at
linuxfoundation.org> wrote:
> > > > On Wed, Jun 09, 2021 at 09:48:33AM +0800, Xuan Zhuo wrote:
> > > > > > > With this patch and the latest net branch I
no longer get crashes.
> > > > > >
> > > > > > Did this ever get properly submitted to the
networking tree to get into
> > > > > > 5.13-final?
> > > > >
> > > > > The patch has been submitted.
> > > > >
> > > > > 	[PATCH net] virtio-net: fix for skb_over_panic inside
big mode
> > > >
> > > > Submitted where?  Do you have a lore.kernel.org link
somewhere?
> > >
> > >
> > > https://lore.kernel.org/netdev/20210603170901.66504-1-xuanzhuo at
linux.alibaba.com/
> >
> > So this is commit 1a8024239dac ("virtio-net: fix for
skb_over_panic
> > inside big mode") in Linus's tree, right?
> 
> YES.
> 
> >
> > But why is that referencing:
> > 	Fixes: fb32856b16ad ("virtio-net: page_to_skb() use build_skb
when there's sufficient tailroom")
> 
> This problem was indeed introduced in fb32856b16ad.
> 
> I confirmed that this commit fb32856b16ad was first entered in 5.13-rc1,
and the
> previous 5.12 did not have this commit fb32856b16ad.
> 
> I'm not sure if it helped you.
Hm, then what resolves the reported problem that people were having with
the 5.12.y kernel release?  Is that a separate issue?

thanks,

greg k-h