Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753333AbaBOO1G (ORCPT ); Sat, 15 Feb 2014 09:27:06 -0500 Received: from mx1.redhat.com ([209.132.183.28]:20480 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753153AbaBOO1E (ORCPT ); Sat, 15 Feb 2014 09:27:04 -0500 Date: Sat, 15 Feb 2014 15:27:00 +0100 From: Oleg Nesterov To: Al Viro Cc: Linus Torvalds , Dave Chinner , Dave Jones , Eric Sandeen , Linux Kernel , xfs@oss.sgi.com Subject: Re: 3.14-rc2 XFS backtrace because irqs_disabled. Message-ID: <20140215142700.GA15540@redhat.com> References: <20140212042215.GN18016@ZenIV.linux.org.uk> <20140212054043.GB13997@dastard> <20140212113928.GO18016@ZenIV.linux.org.uk> <20140212211421.GP18016@ZenIV.linux.org.uk> <20140213174020.GA14455@redhat.com> <20140215052531.GX18016@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140215052531.GX18016@ZenIV.linux.org.uk> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/15, Al Viro wrote: > > OK, _very_ preliminary patch follows. It's uglier than it has to And I'm afraid it needs more uglifications... > +void dismiss_siginfo(ksiginfo_t *info) > +{ > + if (info->q) > + __sigqueue_free(info->q); > + info->q = NULL; > +} 1. info->q can be already freed if SIGQUEUE_PREALLOC. Once get_signal_to_deliver() or any other caller drops ->siglock another thread can do sys_timer_delete()->sigqueue_free(). 2. We need to move do_schedule_next_timer() from dequeue_signal() here. Otherwise ->q can be reused/overwritten by the next send_sigqueue() right affter ->siglock is dropped. Oleg. -- 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/