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From:   Aleksandr Nogikh <nogikh@google.com>
Date:   Wed, 19 Jul 2023 10:45:07 +0200
Message-ID: <CANp29Y6T2sKnnTGtotraCX8saAUw1kSUhS-be=3GM_t+szZ-3Q@mail.gmail.com>
Subject: Re: [syzbot] [bluetooth?] general protection fault in hci_uart_tty_ioctl
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     syzbot <syzbot+c19afa60d78984711078@syzkaller.appspotmail.com>,
        davem@davemloft.net, hdanton@sina.com, jiri@nvidia.com,
        johan.hedberg@gmail.com, linux-bluetooth@vger.kernel.org,
        linux-kernel@vger.kernel.org, luiz.dentz@gmail.com,
        marcel@holtmann.org, netdev@vger.kernel.org,
        syzkaller-bugs@googlegroups.com
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On Tue, Jul 18, 2023 at 9:45=E2=80=AFPM Jakub Kicinski <kuba@kernel.org> wr=
ote:
>
> On Mon, 17 Jul 2023 13:22:24 -0700 syzbot wrote:
> > syzbot suspects this issue was fixed by commit:
> >
> > commit d772781964415c63759572b917e21c4f7ec08d9f
> > Author: Jakub Kicinski <kuba@kernel.org>
> > Date:   Fri Jan 6 06:33:54 2023 +0000
> >
> >     devlink: bump the instance index directly when iterating
>
> Hm, don't think so. It's not the first issue where syzbot decided
> this commit was the resolution. I wonder what makes it special.

Judging by the bisection log, the commit fixed some "INFO: rcu
detected stall in" error that was also triggerable by the reproducer.
Though for me it's not clear how exactly -- at least the reproducer
does not seem to be interacting with devlink..

--=20
Aleksandr


>
> --