From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx110.postini.com [74.125.245.110]) by kanga.kvack.org (Postfix) with SMTP id 6FB938D0003 for ; Fri, 11 May 2012 15:59:23 -0400 (EDT) Date: Fri, 11 May 2012 12:59:21 -0700 From: Andrew Morton Subject: Re: [Bug 43227] New: BUG: Bad page state in process wcg_gfam_6.11_i Message-Id: <20120511125921.a888e12c.akpm@linux-foundation.org> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: bugzilla-daemon@bugzilla.kernel.org, sliedes@cc.hut.fi (switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). On Thu, 10 May 2012 23:29:46 +0000 (UTC) bugzilla-daemon@bugzilla.kernel.org wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=43227 > > Summary: BUG: Bad page state in process wcg_gfam_6.11_i > Product: Memory Management > Version: 2.5 > Kernel Version: 3.3.5 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: Other > AssignedTo: akpm@linux-foundation.org > ReportedBy: sliedes@cc.hut.fi > Regression: No > > > Created an attachment (id=73246) > --> (https://bugzilla.kernel.org/attachment.cgi?id=73246) > Entire dmesg > > Hi, > > I noticed that a number of bad page state bugs have apparently been fixed in > recent stable kernels. Unfortunately it seems there's still some such bug left > in 3.3.5. > > I just saw this bug for the first time after upgrading from (mainline) 3.3.2 to > 3.3.5 (having read the other bug reports I suspect this is the significant > change) and changing my root filesystem from ext4 to xfs, hence causing heavier > exercise of the xfs code than before (but I've had a backup partition on xfs > before with no issues). > > This is the bug I'm seeing: > > [67031.755786] BUG: Bad page state in process wcg_gfam_6.11_i pfn:02519 > [67031.755790] page:ffffea0000094640 count:0 mapcount:0 mapping: > (null) index:0x7f1eb293b > [67031.755792] page flags: 0x4000000000000014(referenced|dirty) AFAICT we got this warning because the page allocator found a free page with PG_referenced and PG_dirty set. It would be a heck of a lot more useful if we'd been told about this when the page was freed, not when it was reused! Can anyone think of a reason why PAGE_FLAGS_CHECK_AT_FREE doesn't include these flags (at least)? > ... > > [67031.755872] Pid: 5229, comm: wcg_gfam_6.11_i Tainted: G O 3.3.5 #2 > [67031.755874] Call Trace: > [67031.755880] [] bad_page+0xcb/0xe0 > [67031.755884] [] get_page_from_freelist+0x54e/0x5f0 > [67031.755888] [] ? string.isra.4+0x3e/0xd0 > [67031.755891] [] __alloc_pages_nodemask+0x115/0x810 > [67031.755895] [] ? seq_printf+0x56/0x90 > [67031.755898] [] ? do_task_stat+0x6ba/0xbf0 > [67031.755901] [] ? anon_vma_prepare+0xfb/0x170 > [67031.755904] [] handle_pte_fault+0x736/0x970 > [67031.755906] [] handle_mm_fault+0x1c8/0x2f0 > [67031.755909] [] do_page_fault+0x16e/0x4f0 > [67031.755913] [] page_fault+0x25/0x30 > [67031.755916] [] ? copy_user_generic_string+0x2d/0x40 > [67031.755919] [] ? seq_read+0x2c8/0x390 > [67031.755922] [] vfs_read+0xa4/0x180 > [67031.755924] [] sys_read+0x45/0x90 > [67031.755927] [] ia32_do_call+0x13/0x13 > [67031.755929] Disabling lock debugging due to kernel taint > > Before that there's a warning about "irq 17: nobody cared" (see the attached > entire dmesg if you are interested); this is apparently an unrelated, known > issue with Asus motherboards which has persisted for a long time without > causing bad page state bugs. > > FWIW, I noticed that a number of the patches that may have something to do with > this and that have gone in since v3.3.2 are KVM related. I have run a large > number of KVM guests on this computer between the boot and this bug occuring, > so this might (or might not) be KVM related. -- 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