From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sukadev Bhattiprolu Subject: Re: [PATCH][usercr]: Ghost tasks must be detached Date: Wed, 9 Feb 2011 11:02:16 -0800 Message-ID: <20110209190216.GA17051@us.ibm.com> References: <20101211033548.GA12584@us.ibm.com> <4D2BB78A.9090701@cs.columbia.edu> <4D4D9D1B.3000209@cs.columbia.edu> <20110205214032.GA12944@us.ibm.com> <4D4DC90B.3010103@cs.columbia.edu> <20110209020942.GA5339@us.ibm.com> <20110209120100.GD13323@hawkmoon.kerlabs.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20110209120100.GD13323-Hu8+6S1rdjywhHL9vcZdMVaTQe2KTcn/@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Oren Laadan , Containers List-Id: containers.vger.kernel.org Louis Rilling [Louis.Rilling-aw0BnHfMbSpBDgjK7y7TUQ@public.gmane.org] wrote: | > | Are we still getting it with 2.6.37 ? | > | > I am not currently getting the crash on 2.6.37 - I thought it was due to | > the following commit which removed the check for task_detached() in | > do_wait_thread(). | > | > commit 9cd80bbb07fcd6d4d037fad4297496d3b132ac6b | > Author: Oleg Nesterov | > Date: Thu Dec 17 15:27:15 2009 -0800 | | I don't think that this introduced the bug. The bug triggers with EXIT_DEAD | tasks, for which wait() must ignore (see below). So, the bug looks still there | in 2.6.37. Sorry, I did not mean to imply that the above commit caused the crash you saw in Jun 2010. I can reproduce a crash with 2.6.32 - where if container-init terminates before a detached child, we get a crash when the detached child calls proc_flush_mnt(). I suspected it was because do_wait_thread() skipped over detached tasks (in 2.6.32). The same test case does not crash on 2.6.37 - which includes the above commit. The removes the check for detached tasks, my initial guess is that the above commit, may have contributed to _fixing_ the crash in 2.6.37. Sukadev