From: Andreas Friedrich Berendsen Subject: Re: possible ext4 race situation freezing linux Date: Wed, 25 Feb 2009 06:03:33 +1300 Message-ID: <1235495013.11758.37.camel@localhost.localdomain> References: <1235478142.11758.9.camel@localhost.localdomain> <20090224141749.GC5482@mit.edu> <49A41469.6090604@redhat.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit To: linux-ext4 Return-path: Received: from rv-out-0506.google.com ([209.85.198.228]:5443 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754389AbZBXRDl (ORCPT ); Tue, 24 Feb 2009 12:03:41 -0500 Received: by rv-out-0506.google.com with SMTP id g37so2556548rvb.1 for ; Tue, 24 Feb 2009 09:03:39 -0800 (PST) In-Reply-To: <49A41469.6090604@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Tso & Eric, I'll try again to reproduce the error, but when the system freezes, I have the X interface running. And, indeed, I'm not familiar with the behaviour of sysreq. Which sysrq should I use when the problem happens? Will the system change to the text interface? If there are no disk activity (all leds are off), where the information will be recorded? -- Berendsen -----Original Message----- From: Eric Sandeen To: Theodore Tso Cc: Andreas Friedrich Berendsen , linux-ext4@vger.kernel.org Subject: Re: possible ext4 race situation freezing linux Date: Tue, 24 Feb 2009 09:38:17 -0600 Theodore Tso wrote: > On Wed, Feb 25, 2009 at 01:22:22AM +1300, Andreas Friedrich Berendsen wrote: >> Kernel version: 2.26.28.7 >> efs2progs version: 1.41.4 >> arch: x86_64 (amd) >> >> I made this test four times and the results were the same: linux >> freezes and becomes unresponsive. Only solution is to reset the box. I >> do not know if the problem is with the USB devices sub-subsystem or a >> possible ext4 race condition. > > Can you use alt-sysrq to get some stack traces or a register dump out, > so we can see where the kernel is hanging? > > - Ted alt-sysrq-w would be a good place to start (just in case you're not familiar w/ the sysrq keys) It'd also be great to test w/ 2.6.29, as a deadlock was fixed there recently (it's on its way to .28.x too AFAIK) Thanks, -Eric -- __________________________________________ Andreas Friedrich Berendsen SCA OCP MSCA A+ Linux+ Network+ HpMASE