From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qc0-f171.google.com (mail-qc0-f171.google.com [209.85.216.171]) by kanga.kvack.org (Postfix) with ESMTP id 5494F6B0035 for ; Wed, 17 Sep 2014 17:38:27 -0400 (EDT) Received: by mail-qc0-f171.google.com with SMTP id x3so1796970qcv.2 for ; Wed, 17 Sep 2014 14:38:27 -0700 (PDT) Received: from aserp1040.oracle.com (aserp1040.oracle.com. [141.146.126.69]) by mx.google.com with ESMTPS id g66si6598389yhc.18.2014.09.17.14.38.26 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 17 Sep 2014 14:38:26 -0700 (PDT) Message-ID: <5419FF2F.4000705@oracle.com> Date: Wed, 17 Sep 2014 17:37:51 -0400 From: Sasha Levin MIME-Version: 1.0 Subject: Re: mm: BUG in unmap_page_range References: <54082B25.9090600@oracle.com> <20140908171853.GN17501@suse.de> <540DEDE7.4020300@oracle.com> <20140909213309.GQ17501@suse.de> <540F7D42.1020402@oracle.com> <20140910124732.GT17501@suse.de> <54110C62.4030702@oracle.com> <20140911162827.GZ17501@suse.de> <5412246E.109@oracle.com> In-Reply-To: <5412246E.109@oracle.com> Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Hugh Dickins , "linux-mm@kvack.org" , Andrew Morton , Dave Jones , LKML , "Kirill A. Shutemov" , Peter Zijlstra , Rik van Riel , Johannes Weiner , Cyrill Gorcunov On 09/11/2014 06:38 PM, Sasha Levin wrote: > On 09/11/2014 12:28 PM, Mel Gorman wrote: >> > Agreed. If 3.17-rc4 looks stable with the VM_BUG_ON then it would be >> > really nice if you could bisect 3.17-rc4 to linux-next carrying the >> > VM_BUG_ON(!(val & _PAGE_PRESENT)) check at each bisection point. I'm not >> > 100% sure if I'm seeing the same corruption as you or some other issue and >> > do not want to conflate numerous different problems into one. I know this >> > is a pain in the ass but if 3.17-rc4 looks stable then a bisection might >> > be faster overall than my constant head scratching :( > The good news are that 3.17-rc4 seems to be stable. I'll start the bisection, > which I suspect would take several days. I'll update when I run into something. I might need a bit of a help here. The bisection is going sideways because I can't reliably reproduce the issue. We don't know what's causing this issue, but we know what the symptoms are. Is there a VM_BUG_ON we could add somewhere so that it would be more likely to trigger? Thanks, Sasha -- 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/ . Don't email: email@kvack.org