Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751532AbaLRRsP (ORCPT ); Thu, 18 Dec 2014 12:48:15 -0500 Received: from shards.monkeyblade.net ([149.20.54.216]:47111 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751117AbaLRRsO (ORCPT ); Thu, 18 Dec 2014 12:48:14 -0500 Date: Thu, 18 Dec 2014 12:48:11 -0500 (EST) Message-Id: <20141218.124811.1240082913671950177.davem@davemloft.net> To: andreas@gaisler.com Cc: sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, software@gaisler.com Subject: Re: [PATCH] sparc32: destroy_context() and switch_mm() needs to disable interrupts. From: David Miller In-Reply-To: <1418905403-11154-1-git-send-email-andreas@gaisler.com> References: <1418905403-11154-1-git-send-email-andreas@gaisler.com> X-Mailer: Mew version 6.5 on Emacs 24.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.7 (shards.monkeyblade.net [149.20.54.216]); Thu, 18 Dec 2014 09:48:13 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andreas Larsson Date: Thu, 18 Dec 2014 13:23:23 +0100 > Load balancing can be triggered in the critical sections protected by > srmmu_context_spinlock in destroy_context() and switch_mm() and can hang > the cpu waiting for the rq lock of another cpu that in turn has called > switch_mm hangning on srmmu_context_spinlock leading to deadlock. > > So, disable interrupt while taking srmmu_context_spinlock in > destroy_context() and switch_mm() so we don't deadlock. > > See also commit 77b838fa1ef0 ("[SPARC64]: destroy_context() needs to disable > interrupts.") > > Signed-off-by: Andreas Larsson Looks good, applied, thanks Andreas. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/