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Date:   Tue, 8 Aug 2023 19:38:54 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Christian Brauner <brauner@kernel.org>, clm@fb.com,
        dsterba@suse.com, josef@toxicpanda.com,
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        syzbot <syzbot+26860029a4d562566231@syzkaller.appspotmail.com>
Subject: Re: [syzbot] [btrfs?] KASAN: slab-use-after-free Read in
 btrfs_open_devices
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On Tue, Aug 08, 2023 at 06:01:41PM +0200, Christoph Hellwig wrote:
> Yes, probably.  The lifetimes looked fishy to me to start with, but
> this might have made things worse.

The locking rules for device structures are not following any commonly
found patterns so it's easy to break it. We've spent a lot of time
chasing races reported by syzbot, so please hold on with this patch
before a final merge. Keeping it in for-next for testing is OK.