From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263040AbVG3Kan (ORCPT ); Sat, 30 Jul 2005 06:30:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263048AbVG3Kan (ORCPT ); Sat, 30 Jul 2005 06:30:43 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:4251 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S263040AbVG3Kaj (ORCPT ); Sat, 30 Jul 2005 06:30:39 -0400 Date: Sat, 30 Jul 2005 12:30:34 +0200 From: Pavel Machek To: Sanjoy Mahajan Cc: linux-kernel@vger.kernel.org, acpi-devel@lists.sourceforge.net Subject: Re: [ACPI] S3 and sigwait (was Re: 2.6.13-rc3: swsusp works (TP 600X)) Message-ID: <20050730103034.GC1942@elf.ucw.cz> References: <20050723003544.GC1988@elf.ucw.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > >> One other glitch is that pdnsd (a nameserver caching daemon) has crashed > >> when the system wakes up from swsusp. It also happens when waking up > >> from S3, which was working with 2.6.11.4 although not with 2.6.13-rc3. > >> Many people have said mysql also does not suspend well. Is their use of > >> a named pipe or socket causing the problem? > > > No idea, strace? > > The upshot of stracing is in tthe Debian BTS > #319572. Paul Rombouts, an author of pdnsd, reproduced the strace > crash and found the problem: > > > Apparently strace causes sigwait to return EINTR, which is > > inconsistent with the documentation I could find on sigwait. > > Which is true. The sigwait man entry (Debian 'etch') says: > The !sigwait! function never returns an error. > > His patch (available in the BTS and included below) fixed the problem > of strace or S3 sleep crashing pdnsd. If you think it is a linux bug, can you produce small test case doing just the sigwait, and post it on l-k with big title "sigwait() breaks when straced, and on suspend"? That way it is going to get some attetion, and you'll get either documentation or kernel fixed. Pavel -- teflon -- maybe it is a trademark, but it should not be.