On Sat, Oct 09, 2021 at 12:27:08AM +0800, Xuan Zhuo wrote:

On Fri, 8 Oct 2021 10:06:57 +0200, Greg KH gregkh@linuxfoundation.org wrote:

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On Fri, Oct 08, 2021 at 12:17:26AM +0800, Xuan Zhuo wrote:

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On Thu, 7 Oct 2021 17:25:02 +0200, Greg KH gregkh@linuxfoundation.org wrote:

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On Thu, Oct 07, 2021 at 11:06:12PM +0800, Xuan Zhuo wrote:

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On Thu, 07 Oct 2021 14:04:22 +0200, Corentin Noël corentin.noel@collabora.com wrote:

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I've been experiencing crashes with 5.14-rc1 and above that do not occur with 5.13,

I should have fixed this problem before. I don't know why, I just looked at the latest net code, and this commit seems to be lost.

 1a8024239dacf53fcf39c0f07fbf2712af22864f virtio-net: fix for skb_over_panic inside big mode

Can you test this patch again?

That commit showed up in 5.13-rc5, so 5.14-rc1 and 5.13 should have had it in it, right?

Yes, it may be lost due to conflicts during a certain merge.

Really? I tried to apply that again to 5.14 and it did not work. So I do not understand what to do here, can you try to explain it better?

I took a look, and there is actually another missing patch:

A. 8fb7da9e990793299c89ed7a4281c235bfdd31f8 virtio_net: get build_skb() buf by data ptr B. 1a8024239dacf53fcf39c0f07fbf2712af22864f virtio-net: fix for skb_over_panic inside big mode

A is replaced by another patch:

commit c32325b8fdf2f979befb9fd5587918c0d5412db3 Author: Jakub Kicinski kuba@kernel.org Date: Mon Aug 2 10:57:29 2021 -0700

   virtio-net: realign page_to_skb() after merges

   We ended up merging two versions of the same patch set:

   commit 8fb7da9e9907 ("virtio_net: get build_skb() buf by data ptr")
   commit 5c37711d9f27 ("virtio-net: fix for unable to handle page fault for address")

   into net, and

   commit 7bf64460e3b2 ("virtio-net: get build_skb() buf by data ptr")
   commit 6c66c147b9a4 ("virtio-net: fix for unable to handle page fault for address")

   into net-next. Redo the merge from commit 126285651b7f ("Merge
   ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net"), so that
   the most recent code remains.

   Acked-by: Michael S. Tsirkin <mst@redhat.com>
   Signed-off-by: Jakub Kicinski <kuba@kernel.org>
   Acked-by: Jason Wang <jasowang@redhat.com>
   Signed-off-by: David S. Miller <davem@davemloft.net>

So after this patch, patch B can be applied normally.

So on the latest net branch, only lost

      1a8024239dacf53fcf39c0f07fbf2712af22864f virtio-net: fix for skb_over_panic inside big mode

Again, I do not know what to do here, can you submit the needed fix to the networking developers so this gets fixed?

thanks,

greg k-h