From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <axboe@kernel.dk>
Subject: Re: [PATCH] blk-mq: Take tagset lock when updaing hw queues
To: Keith Busch <keith.busch@intel.com>, linux-block@vger.kernel.org
Cc: Bart Van Assche <Bart.VanAssche@sandisk.com>,
 Gabriel Krisman Bertazi <krisman@collabora.co.uk>,
 linux-nvme@lists.infradead.org
References: <1496169551-26868-1-git-send-email-keith.busch@intel.com>
From: Jens Axboe <axboe@kernel.dk>
Message-ID: <56ed7162-5397-b4dd-14d2-1e017c6b7c33@kernel.dk>
Date: Tue, 30 May 2017 12:32:59 -0600
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In-Reply-To: <1496169551-26868-1-git-send-email-keith.busch@intel.com>
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On 05/30/2017 12:39 PM, Keith Busch wrote:
> The tagset lock needs to be held when iterating the tag_list, so a
> lockdep assert was added when updating number of hardware queues. The
> drivers calling this API, however, were unaware of the new requirement,
> so are failing the assertion.
> 
> This patch takes the lock within the blk-mq function so the drivers do
> not have to be modified in order to be safe.

Thanks Keith, applied for 4.12 with the typo in the subject line fixed
up.

-- 
Jens Axboe