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Message-ID: <11868eb4-0528-4298-b8bc-2621fd1aac83@kernel.dk>
Date: Thu, 25 Jan 2024 09:11:34 -0700
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From: Jens Axboe <axboe@kernel.dk>
Subject: Re: [syzbot] [jfs?] INFO: task hung in path_mount (2)
To: Christian Brauner <brauner@kernel.org>
Cc: syzbot <syzbot+fb337a5ea8454f5f1e3f@syzkaller.appspotmail.com>,
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On Thu, Jan 25, 2024 at 9:08?AM Christian Brauner <brauner@kernel.org> wrote:
>
> On Thu, Jan 25, 2024 at 03:59:03AM -0800, syzbot wrote:
> > syzbot suspects this issue was fixed by commit:
> >
> > commit 6f861765464f43a71462d52026fbddfc858239a5
> > Author: Jan Kara <jack@suse.cz>
> > Date:   Wed Nov 1 17:43:10 2023 +0000
> >
> >     fs: Block writes to mounted block devices
> >
> > bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=13175a53e80000
> > start commit:   2ccdd1b13c59 Linux 6.5-rc6
> > git tree:       upstream
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=9c37cc0e4fcc5f8d
> > dashboard link: https://syzkaller.appspot.com/bug?extid=fb337a5ea8454f5f1e3f
> > syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17ba5d53a80000
> > C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14265373a80000
> >
> > If the result looks correct, please mark the issue as fixed by replying with:
>
> #syz fix: fs: Block writes to mounted block devices

Like Dave replied a few days ago, I'm kind of skeptical on all of these
bugs being closed by this change. I'm guessing that they are all
resolved now because a) the block writes while mounted option was set to
Y, and b) the actual bug is just masked by that.

Maybe this is fine, but it does seem a bit... sketchy? The bugs aren't
really fixed, and what happens if someone doesn't turn on that option?
If it's required, perhaps it should not be an option at all? Though
that'd seem to be likely to break some funky use cases, whether they are
valid or not.

-- 
Jens Axboe