Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934111AbXFFAES (ORCPT ); Tue, 5 Jun 2007 20:04:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764804AbXFFAEJ (ORCPT ); Tue, 5 Jun 2007 20:04:09 -0400 Received: from gate.crashing.org ([63.228.1.57]:47830 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764245AbXFFAEI (ORCPT ); Tue, 5 Jun 2007 20:04:08 -0400 Subject: Re: [PATCH/RFC] signal races/bugs, losing TIF_SIGPENDING and other woes From: Benjamin Herrenschmidt To: Nicholas Miell Cc: Davide Libenzi , Linus Torvalds , Linux Kernel list , Andrew Morton , Paul Mackerras In-Reply-To: <1181087462.2788.8.camel@entropy> References: <1181006711.31677.97.camel@localhost.localdomain> <1181009413.31677.117.camel@localhost.localdomain> <1181013756.31677.123.camel@localhost.localdomain> <1181023787.2785.14.camel@entropy> <1181028453.31677.127.camel@localhost.localdomain> <1181087462.2788.8.camel@entropy> Content-Type: text/plain Date: Wed, 06 Jun 2007 10:03:58 +1000 Message-Id: <1181088238.31677.150.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: 999 Lines: 24 On Tue, 2007-06-05 at 16:51 -0700, Nicholas Miell wrote: > Yes, that's certainly wrong, but that's an implementation issue. I was > more concerned about the design of the API. > > Naively, I would expect a reads on a signalfd to return either process > signals or thread signals targeted towards the thread doing the read. > > What it actually does (delivering process signals or thread signals > targeted towards the thread that created the signalfd) is weird. > > For one, it means you can't create a single signalfd, stick it in an > epoll set, and then wait on that set from multiple threads. Heh, well, I'll let you discuss that apsect with Davide. Right now, I'm just trying to make sure that the implementation in the kernel copes :-) 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/