Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762946AbXFEDWx (ORCPT ); Mon, 4 Jun 2007 23:22:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756873AbXFEDWo (ORCPT ); Mon, 4 Jun 2007 23:22:44 -0400 Received: from gate.crashing.org ([63.228.1.57]:48704 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756130AbXFEDWn (ORCPT ); Mon, 4 Jun 2007 23:22:43 -0400 Subject: Re: [PATCH/RFC] signal races/bugs, losing TIF_SIGPENDING and other woes From: Benjamin Herrenschmidt To: Davide Libenzi Cc: Linus Torvalds , Linux Kernel list , Andrew Morton , Paul Mackerras In-Reply-To: References: <1181006711.31677.97.camel@localhost.localdomain> <1181009413.31677.117.camel@localhost.localdomain> Content-Type: text/plain Date: Tue, 05 Jun 2007 13:22:36 +1000 Message-Id: <1181013756.31677.123.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.10.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1221 Lines: 26 On Mon, 2007-06-04 at 19:38 -0700, Davide Libenzi wrote: > > - I still think there's something wrong with dequeue_signal() being > > potentially called with a task different than current by signalfd, since > > __dequeue_signal() (among others) mucks around with current regardless. > > I'd love to just make signalfd's read() only do anything if current == > > ctx->tsk and remove the task argument from dequeue_signal... that would > > fix it nicely too no ? > > There's got to be a clean solution that does not limit signalfd, no? I > have no time to look at it immediately, but I can look into it in the > next few days, if someone else does not do it before... Is there a real usage to dequeuing somebody else signals with signalfd ? If yes, then we can do something around the lines of passing task down to __dequeue_signal, though I'm not too sure waht this notifier is about and wether it might rely on being called from within the affected task context... Ben. - 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/