From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753647AbZEaRri (ORCPT ); Sun, 31 May 2009 13:47:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751583AbZEaRr3 (ORCPT ); Sun, 31 May 2009 13:47:29 -0400 Received: from smtp02.lnh.mail.rcn.net ([207.172.157.102]:52265 "EHLO smtp02.lnh.mail.rcn.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750866AbZEaRr3 (ORCPT ); Sun, 31 May 2009 13:47:29 -0400 Subject: Re: [PATCH] coredump: Retry writes where appropriate From: Paul Smith Reply-To: paul@mad-scientist.net To: Alan Cox Cc: Olivier Galibert , linux-kernel@vger.kernel.org, stable@kernel.org, Andrew Morton , Andi Kleen , Oleg Nesterov , Roland McGrath In-Reply-To: <20090531173144.0a552386@lxorguk.ukuu.org.uk> References: <1243748019.7369.319.camel@homebase.localnet> <20090531111851.07eb1df3@lxorguk.ukuu.org.uk> <20090531140354.GA92675@dspnet.fr.eu.org> <20090531173144.0a552386@lxorguk.ukuu.org.uk> Content-Type: text/plain Content-Transfer-Encoding: 7bit Organization: GNU's Not Unix! Date: Sun, 31 May 2009 13:46:19 -0400 Message-Id: <1243791979.7369.385.camel@homebase.localnet> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2009-05-31 at 17:31 +0100, Alan Cox wrote: > The only source of signals during a dump should be external ones. Far > better would be to set some kind of defined signal mask during the dump > (say SIGPIPE, SIGINT, SIGQUIT) ? I agree with Paul's patch in the sense > we don't want spurious SIGIO events or similar spoiling a dump. Something similar to this is what Andi Kleen first proposed. The issue is that it modifies the signal mask for the process before the core was dumped, so that the mask saved in the core was not the real mask used by the process when it took the exception. Andi mentioned this problem and suggested we'd need to keep the original mask around to be saved in the core. That would involve deeper hacking in the ELF format but maybe this is the right answer.