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Date:   Wed, 21 Jun 2023 18:26:24 +0200
From:   Jan Kara <jack@suse.cz>
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Jan Kara <jack@suse.cz>, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org, linux-ext4@vger.kernel.org,
        linux-xfs@vger.kernel.org
Subject: Re: [PATCH 1/2] ext4: Fix crash in ext4_bdev_mark_dead()
Message-ID: <20230621162624.efgmx6lguqjnxcqv@quack3>
References: <20230621144354.10915-1-jack@suse.cz>
 <20230621144744.1580-1-jack@suse.cz>
 <ZJMOqynQKadyBOXX@infradead.org>
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On Wed 21-06-23 07:52:27, Christoph Hellwig wrote:
> On Wed, Jun 21, 2023 at 04:47:42PM +0200, Jan Kara wrote:
> > ext4_bdev_mark_dead() passes bdev->bd_holder to ext4_force_shutdown()
> > instead of bdev->bd_super leading to crashes. Fix it.
> 
> How does this crash? ext4_blkdev_get passes the sb as holder, and I
> actually tested this code.
> 
> This is not to be confused with the blkdev_get_by_path in get_tree_bdev,
> but that never ends up in ext4_bdev_mark_dead.

Indeed, I have confused the method called for journal device with the
method called for the main filesystem device. Both my patches are wrong and
I'm sorry for the confusion!

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR