From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id 970788D0040 for ; Mon, 28 Mar 2011 20:25:28 -0400 (EDT) Received: from hpaq2.eem.corp.google.com (hpaq2.eem.corp.google.com [172.25.149.2]) by smtp-out.google.com with ESMTP id p2T0PPt6031673 for ; Mon, 28 Mar 2011 17:25:25 -0700 Received: from yie16 (yie16.prod.google.com [10.243.66.16]) by hpaq2.eem.corp.google.com with ESMTP id p2T0On2n002695 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Mon, 28 Mar 2011 17:25:24 -0700 Received: by yie16 with SMTP id 16so1338878yie.16 for ; Mon, 28 Mar 2011 17:25:24 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <081DDE43F61F3D43929A181B477DCA95639B534E@MSXAOA6.twosigma.com> References: <081DDE43F61F3D43929A181B477DCA95639B52FD@MSXAOA6.twosigma.com> <081DDE43F61F3D43929A181B477DCA95639B5327@MSXAOA6.twosigma.com> <20110324174311.GA31576@infradead.org> <081DDE43F61F3D43929A181B477DCA95639B5349@MSXAOA6.twosigma.com> <081DDE43F61F3D43929A181B477DCA95639B534E@MSXAOA6.twosigma.com> Date: Mon, 28 Mar 2011 17:25:24 -0700 Message-ID: Subject: Re: XFS memory allocation deadlock in 2.6.38 From: Michel Lespinasse Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Sean Noonan Cc: Christoph Hellwig , "linux-kernel@vger.kernel.org" , Martin Bligh , Trammell Hudson , Christos Zoulas , "linux-xfs@oss.sgi.com" , Stephen Degler , "linux-mm@kvack.org" , Dave Chinner On Mon, Mar 28, 2011 at 2:34 PM, Sean Noonan wrote: >> Could you test if you see the deadlock before >> 5ecfda041e4b4bd858d25bbf5a16c2a6c06d7272 without MAP_POPULATE ? > > Built and tested 72ddc8f72270758951ccefb7d190f364d20215ab. > Confirmed that the original bug does not present in this version. > Confirmed that removing MAP_POPULATE does cause the deadlock to occur. It seems that the test (without MAP_POPULATE) reveals that the root cause is an xfs bug, which had been hidden up to now by MAP_POPULATE preallocating disk blocks (but could always be triggered by the same test without the MAP_POPULATE flag). I'm not sure how to go about debugging the xfs deadlock; it would probably be best if an xfs person could have a look ? -- Michel "Walken" Lespinasse A program is never fully debugged until the last user dies. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org