Re: [syzbot] WARNING: suspicious RCU usage (5)

[Xuan Zhuo]

On Thu, 23 Jun 2022 00:35:13 -0700, syzbot <syzbot+9cbc6bed3a22f1d37395@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> syzbot has bisected this issue to:
>
> commit c2ff53d8049f30098153cd2d1299a44d7b124c57
> Author: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
> Date:   Thu Feb 18 20:50:02 2021 +0000
>
>     net: Add priv_flags for allow tx skb without linear
>
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=11596838080000
> start commit:   a5b00f5b78b7 Merge branch 'hns3-fixres'
> git tree:       net
> final oops:     https://syzkaller.appspot.com/x/report.txt?x=13596838080000
> console output: https://syzkaller.appspot.com/x/log.txt?x=15596838080000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=20ac3e0ebf0db3bd
> dashboard link: https://syzkaller.appspot.com/bug?extid=9cbc6bed3a22f1d37395
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=143b22abf00000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=125194eff00000
>
> Reported-by: syzbot+9cbc6bed3a22f1d37395@xxxxxxxxxxxxxxxxxxxxxxxxx
> Fixes: c2ff53d8049f ("net: Add priv_flags for allow tx skb without linear")


I think it's unlikely that my patch is causing the problem, because my patch is
very simple and doesn't have any effect on the kernel. I don't know if there is
something wrong.

I used the above config (make olddefconfig) to compile this commit, and it
crashed directly after starting it in qemu.

Thanks.


>
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection