From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752727AbdKVClQ (ORCPT ); Tue, 21 Nov 2017 21:41:16 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:57481 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752709AbdKVClO (ORCPT ); Tue, 21 Nov 2017 21:41:14 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Johannes Thumshirn" , "Christoph Hellwig" , "Jens Axboe" , "Bart Van Assche" , "Hannes Reinecke" , "Andrew Morton" , "Paolo 'Blaisorblade' Giarrusso" Date: Wed, 22 Nov 2017 01:58:12 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 039/133] block: Relax a check in blk_start_queue() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.51-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche commit 4ddd56b003f251091a67c15ae3fe4a5c5c5e390a upstream. Calling blk_start_queue() from interrupt context with the queue lock held and without disabling IRQs, as the skd driver does, is safe. This patch avoids that loading the skd driver triggers the following warning: WARNING: CPU: 11 PID: 1348 at block/blk-core.c:283 blk_start_queue+0x84/0xa0 RIP: 0010:blk_start_queue+0x84/0xa0 Call Trace: skd_unquiesce_dev+0x12a/0x1d0 [skd] skd_complete_internal+0x1e7/0x5a0 [skd] skd_complete_other+0xc2/0xd0 [skd] skd_isr_completion_posted.isra.30+0x2a5/0x470 [skd] skd_isr+0x14f/0x180 [skd] irq_forced_thread_fn+0x2a/0x70 irq_thread+0x144/0x1a0 kthread+0x125/0x140 ret_from_fork+0x2a/0x40 Fixes: commit a038e2536472 ("[PATCH] blk_start_queue() must be called with irq disabled - add warning") Signed-off-by: Bart Van Assche Cc: Paolo 'Blaisorblade' Giarrusso Cc: Andrew Morton Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Johannes Thumshirn Signed-off-by: Jens Axboe [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings --- block/blk-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/block/blk-core.c +++ b/block/blk-core.c @@ -198,7 +198,7 @@ EXPORT_SYMBOL(blk_delay_queue); **/ void blk_start_queue(struct request_queue *q) { - WARN_ON(!irqs_disabled()); + WARN_ON(!in_interrupt() && !irqs_disabled()); queue_flag_clear(QUEUE_FLAG_STOPPED, q); __blk_run_queue(q);