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Date:   Thu, 13 Apr 2023 15:55:01 +0200
From:   Frederic Weisbecker <frederic@kernel.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Pengfei Xu <pengfei.xu@intel.com>, lihuafei1@huawei.com,
        rostedt@goodmis.org, linux-kernel@vger.kernel.org, lkp@intel.com,
        quic_neeraju@quicinc.com, paulmck@kernel.org, heng.su@intel.com
Subject: Re: [Syzkaller & bisect] There is "task hung in synchronize_rcu
 bisect" in v6.3-rc2 kernel
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References: <ZBG4HOCQIlGFFcIn@xpf.sh.intel.com>
 <ZDdsz+5/QehZ25hg@xpf.sh.intel.com>
 <ZDflLOCujdBNXl3D@lothringen>
 <441aa796-5c39-1cf5-c71a-f04633773968@kernel.dk>
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Le Thu, Apr 13, 2023 at 06:40:16AM -0600, Jens Axboe a ?crit :
> Is there a reproducer for this one so we can take a look? It's not
> impossible to get into this state if you muck with signals, eg ring
> exit work is queued but needs requests to complete, and the latter
> is prevented by deliberately sending a SIGSTOP to the task that needs
> to complete them.

Yep, the original message provides all the necessary steps to reproduce:

     https://lore.kernel.org/lkml/ZBG4HOCQIlGFFcIn@xpf.sh.intel.com/

I cross my fingers that you'll be able to trigger it...

Thanks.