From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f44.google.com (mail-pa0-f44.google.com [209.85.220.44]) by kanga.kvack.org (Postfix) with ESMTP id 26DE86B0038 for ; Wed, 21 Oct 2015 21:00:19 -0400 (EDT) Received: by pacfv9 with SMTP id fv9so73078369pac.3 for ; Wed, 21 Oct 2015 18:00:18 -0700 (PDT) Received: from mail-pa0-x22a.google.com (mail-pa0-x22a.google.com. [2607:f8b0:400e:c03::22a]) by mx.google.com with ESMTPS id tb8si17044714pab.225.2015.10.21.18.00.18 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 21 Oct 2015 18:00:18 -0700 (PDT) Received: by padhk11 with SMTP id hk11so70098804pad.1 for ; Wed, 21 Oct 2015 18:00:18 -0700 (PDT) Date: Wed, 21 Oct 2015 17:59:59 -0700 (PDT) From: Hugh Dickins Subject: Re: kernel oops on mmotm-2015-10-15-15-20 In-Reply-To: <20151022000648.GD23631@bbox> Message-ID: References: <20151021052836.GB6024@bbox> <20151021110723.GC10597@node.shutemov.name> <20151022000648.GD23631@bbox> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: "Kirill A. Shutemov" , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Hugh Dickins , Rik van Riel , Mel Gorman , Michal Hocko , Johannes Weiner , Vlastimil Babka On Thu, 22 Oct 2015, Minchan Kim wrote: > > I added the code to check it and queued it again but I had another oops > in this time but symptom is related to anon_vma, too. > (kernel is based on recent mmotm + unconditional mkdirty for bug fix) > It seems page_get_anon_vma returns NULL since the page was not page_mapped > at that time but second check of page_mapped right before try_to_unmap seems > to be true. > > Adding 4191228k swap on /dev/vda5. Priority:-1 extents:1 across:4191228k FS > Adding 4191228k swap on /dev/vda5. Priority:-1 extents:1 across:4191228k FS > page:ffffea0001cfbfc0 count:3 mapcount:1 mapping:ffff88007f1b5f51 index:0x600000aff > flags: 0x4000000000048019(locked|uptodate|dirty|swapcache|swapbacked) > page dumped because: VM_BUG_ON_PAGE(PageAnon(page) && !PageKsm(page) && !anon_vma) That's interesting, that's one I added in my page migration series. Let me think on it, but it could well relate to the one you got before. > page->mem_cgroup:ffff88007f3dcc00 > ------------[ cut here ]------------ > kernel BUG at mm/migrate.c:889! > invalid opcode: 0000 [#1] SMP > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 11 PID: 59 Comm: khugepaged Not tainted 4.3.0-rc6-next-20151021-THP-ref-madv_free+ #1557 Hmm, it might be me to blame, or it might be Kirill, don't know yet. Oh, hold on, I think Andrew has just posted a new mmotm, and it includes an update to Kirill's migrate_pages-try-to-split-pages-on-queueing.patch: I haven't digested yet, but it might turn out to be relevant. Hugh -- 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