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Date: Thu, 3 Oct 2024 11:30:44 -1000
From: Tejun Heo <tj@kernel.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: Dan Carpenter <dan.carpenter@linaro.org>,
	Waiman Long <longman@redhat.com>, Yu Kuai <yukuai3@huawei.com>,
	Josef Bacik <josef@toxicpanda.com>, cgroups@vger.kernel.org,
	linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
	kernel-janitors@vger.kernel.org, Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH v2] blk_iocost: remove some duplicate irq disable/enables
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On Thu, Oct 03, 2024 at 11:22:09AM -1000, Tejun Heo wrote:
> Yeah, that should be spin_lock_irq() for consistency but at the same time it
> doesn't look like anything is actually grabbing that lock (or blkcg->lock
> nesting outside of it) from an IRQ context, so no actual deadlock scenario
> exists and lockdep doesn't trigger.

Oh, wait, it's not that. blkg_conf_prep() implies queue_lock, so the IRQ is
disabled around it and adding _irq will trigger lockdep.

Thanks.

-- 
tejun