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Date: Mon, 30 Jun 2025 18:42:49 -0600
From: Keith Busch <kbusch@kernel.org>
To: Bart Van Assche <bvanassche@acm.org>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	linux-block@vger.kernel.org, Nilay Shroff <nilay@linux.ibm.com>,
	stable@vger.kernel.org
Subject: Re: [PATCH v2] block: Fix a deadlock related to modifying the
 readahead attribute
Message-ID: <aGMvCXklxJ_rlZOM@kbusch-mbp>
References: <20250626203713.2258558-1-bvanassche@acm.org>
 <20250627071702.GA992@lst.de>
 <d03ccb5c-f44c-40e7-9964-2e9ec67bb96f@acm.org>
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In-Reply-To: <d03ccb5c-f44c-40e7-9964-2e9ec67bb96f@acm.org>

On Mon, Jun 30, 2025 at 03:39:18PM -0700, Bart Van Assche wrote:
> On 6/27/25 12:17 AM, Christoph Hellwig wrote:
> > Well, if there are queued never completed bios the freeze will obviously
> > fail.  I don't see how this freeze is special vs other freezes or other
> > attributes that freeze.
> 
> Hi Christoph,
> 
> Do you perhaps want me to remove the freeze/unfreeze calls from all
> sysfs store callbacks from which it is safe to remove these callbacks?

But don't the remaining attributes that are not safe remain susceptible
to this deadlock?