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Date:   Sat, 26 Mar 2022 21:24:10 +0900
From:   asmadeus@codewreck.org
To:     Christian Schoenebeck <linux_oss@crudebyte.com>
Cc:     David Kahurani <k.kahurani@gmail.com>, davem@davemloft.net,
        ericvh@gmail.com, kuba@kernel.org, linux-kernel@vger.kernel.org,
        lucho@ionkov.net, netdev@vger.kernel.org,
        syzkaller-bugs@googlegroups.com,
        v9fs-developer@lists.sourceforge.net,
        syzbot+5e28cdb7ebd0f2389ca4@syzkaller.appspotmail.com
Subject: Re: [syzbot] WARNING in p9_client_destroy
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References: <CAAZOf26g-L2nSV-Siw6mwWQv1nv6on8c0fWqB4bKmX73QAFzow@mail.gmail.com>
 <3597833.OkAhqpS0b6@silver>
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Christian Schoenebeck wrote on Sat, Mar 26, 2022 at 12:48:26PM +0100:
> [...]
>
> > Signed-off-by: David Kahurani <k.kahurani@gmail.com>
> > Reported-by: syzbot+5e28cdb7ebd0f2389ca4@syzkaller.appspotmail.com

Looks good to me - it's pretty much what I'd have done if I hadn't
forgotten!
It doesn't strike me as anything critical and I don't have anything else
for this cycle so I'll just queue it in -next for now, and submit it
at the start of the 5.19 cycle in ~2months.

> I'm not absolutely sure that this will really fix this issue, but it seems to 
> be a good idea to add a rcu_barrier() call here nevertheless.

Yeah, I'm not really sure either but this is the only idea I have given
the debug code doesn't list anything left in the cache, and David came
to the same conclusion :/

Can't hurt though, so let's try and see if syzbot complains
again. Thanks for the review!

-- 
Dominique