From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Gabriel Krisman Bertazi To: Keith Busch Cc: Jens Axboe , linux-block@vger.kernel.org, Bart Van Assche , linux-nvme@lists.infradead.org Subject: Re: [PATCH] blk-mq: Take tagset lock when updaing hw queues References: <1496169551-26868-1-git-send-email-keith.busch@intel.com> Date: Tue, 30 May 2017 16:52:14 -0300 In-Reply-To: <1496169551-26868-1-git-send-email-keith.busch@intel.com> (Keith Busch's message of "Tue, 30 May 2017 14:39:11 -0400") Message-ID: <87fufmm8b5.fsf@dilma.collabora.co.uk> MIME-Version: 1.0 Content-Type: text/plain List-ID: Keith Busch writes: > 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. > > Fixes: 705cda97e ("blk-mq: Make it safe to use RCU to iterate over blk_mq_tag_set.tag_list") > > Reported-by: Gabriel Krisman Bertazi > Reviewed-by: Bart Van Assche > Signed-off-by: Keith Busch I know it is already applied but, FWIW, I can confirm it fixed the issue in our CI. Feel free to add: Tested-by: Gabriel Krisman Bertazi Thanks again, Keith. -- Gabriel Krisman Bertazi