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From:   Palash Oswal <oswalpalash@gmail.com>
Date:   Sun, 2 May 2021 20:31:03 +0530
Message-ID: <CAGyP=7fAsgXjaK9MHOCLAWLY9ay6Z03KtxaFQVcNtk25KQ5poQ@mail.gmail.com>
Subject: Re: INFO: task hung in io_uring_cancel_sqpoll
To:     Pavel Begunkov <asml.silence@gmail.com>,
        Hillf Danton <hdanton@sina.com>
Cc:     Jens Axboe <axboe@kernel.dk>, io-uring@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        syzbot+11bf59db879676f59e52@syzkaller.appspotmail.com
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On Sun, May 2, 2021 at 4:04 PM Pavel Begunkov <asml.silence@gmail.com> wrote:

> > I tested against the HEAD b1ef997bec4d5cf251bfb5e47f7b04afa49bcdfe
>
> However, there is a bunch patches fixing sqpoll cancellations in
> 5.13, all are waiting for backporting. and for-next doesn't trigger
> the issue for me.
>
> Are you absolutely sure b1ef997bec4d5cf251bfb5e47f7b04afa49bcdfe
> does hit it?
>
> > commit on for-next tree
> > https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/?h=for-next
> > and the reproducer fails.

Hi Pavel and Hillf,

I believe there's a little misunderstanding, apologies. The reproducer
does not trigger the bug on the for-next tree which has patches for
5.13. The reproducer process exits correctly. Likely one of those
commits that will be back-ported to 5.12 will address this issue.
When I wrote `the reproducer fails`, I meant to indicate that the bug
is not triggered on for-next. I will word it better next time!

Palash