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Date:   Mon, 31 Jul 2023 15:57:50 +0200
From:   Christian Brauner <brauner@kernel.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Gao Xiang <hsiangkao@linux.alibaba.com>,
        syzbot <syzbot+69c477e882e44ce41ad9@syzkaller.appspotmail.com>,
        chao@kernel.org, huyue2@coolpad.com, jack@suse.cz,
        jefflexu@linux.alibaba.com, linkinjeon@kernel.org,
        linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org, sj1557.seo@samsung.com,
        syzkaller-bugs@googlegroups.com, xiang@kernel.org
Subject: Re: [syzbot] [erofs?] [fat?] WARNING in erofs_kill_sb
Message-ID: <20230731-deswegen-chatten-4ff6c45563ad@brauner>
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On Mon, Jul 31, 2023 at 03:53:25PM +0200, Christoph Hellwig wrote:
> On Mon, Jul 31, 2023 at 03:22:28PM +0200, Christian Brauner wrote:
> > Uh, no. I vasty underestimated how sensitive that change would be. Plus
> > arguably ->kill_sb() really should be callable once the sb is visible.
> > 
> > Are you looking into this or do you want me to, Christoph?
> 
> I'm planning to look into it, but I won't get to it before tomorrow.

Ok, let me go through the callsites and make sure that all callers are
safe. I think we should just continue calling deactivate_locked_super()
exactly the way we do right now but remove shenanigans like the one we
have in erofs_kill_sb().