From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH 0/2] drmtest: Fix hanging child processes Date: Tue, 3 Dec 2013 17:59:49 +0100 Message-ID: <20131203165949.GK27344@phenom.ffwll.local> References: <1386089095-9966-1-git-send-email-tvrtko.ursulin@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ee0-f42.google.com (mail-ee0-f42.google.com [74.125.83.42]) by gabe.freedesktop.org (Postfix) with ESMTP id BFB6FFB4AA for ; Tue, 3 Dec 2013 08:59:03 -0800 (PST) Received: by mail-ee0-f42.google.com with SMTP id e53so680026eek.15 for ; Tue, 03 Dec 2013 08:59:03 -0800 (PST) Content-Disposition: inline In-Reply-To: <1386089095-9966-1-git-send-email-tvrtko.ursulin@linux.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org To: Tvrtko Ursulin Cc: Intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, Dec 03, 2013 at 04:44:53PM +0000, Tvrtko Ursulin wrote: > From: Tvrtko Ursulin > > It was observed both on Linux and Android that tests which > fork can sometimes hang failing to terminate child > processes. > > This was eventually tracked down to race conditions in C > library implementations, all with regards to caching of > PID/TGID and TID values. > > Solution is to revert the previous workaround, which closed > the race under glibc a bit, and ensure current values from > the kernel are used during timing sensitive periods. > > This was tested under Android only but should be a generic fix. > > Tvrtko Ursulin (2): > Revert "lib/drmtest: ducttape over fork race" > drmtest: Avoid wrong PID/TID after clone races Both merged, thanks for the patches. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch