Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753407AbaBOPW7 (ORCPT ); Sat, 15 Feb 2014 10:22:59 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:52930 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753361AbaBOPW6 (ORCPT ); Sat, 15 Feb 2014 10:22:58 -0500 Date: Sat, 15 Feb 2014 15:22:51 +0000 From: Al Viro To: Oleg Nesterov 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: <20140215152251.GY18016@ZenIV.linux.org.uk> References: <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> <20140215142700.GA15540@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140215142700.GA15540@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 15, 2014 at 03:27:00PM +0100, Oleg Nesterov wrote: > 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(). How the devil would it find the sucker? It's off the list already. > 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. Ditto. We rip them out of queue on collect_signal(); the only thing we do not do is actual __sigqueue_free(). -- 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/