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Date: Thu, 3 Apr 2025 07:44:57 +0200
From: Christoph Hellwig <hch@lst.de>
To: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
	Valdis =?utf-8?Q?Kl=C4=93tnieks?= <valdis.kletnieks@vt.edu>,
	Nilay Shroff <nilay@linux.ibm.com>, Christoph Hellwig <hch@lst.de>,
	syzbot+4c7e0f9b94ad65811efb@syzkaller.appspotmail.com
Subject: Re: [PATCH V2 3/3] block: use blk_mq_no_io() for avoiding lock
 dependency
Message-ID: <20250403054457.GC24133@lst.de>
References: <20250403025214.1274650-1-ming.lei@redhat.com> <20250403025214.1274650-4-ming.lei@redhat.com>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Thu, Apr 03, 2025 at 10:52:10AM +0800, Ming Lei wrote:
> Lock implied in blk_mq_enter_no_io() won't connect with any lock in IO
> code paths now, so use it to prevent IO from entering queue for avoiding
> lock dependency between freeze lock and elevator lock, and we have got
> many such reports.

Please explain what this actually fixes here.