From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Christopher S. Aker" Subject: Re: [Xen-devel] Re: kernel BUG at mm/swapfile.c:2527! [was 3.0.0 Xen pv guest - BUG: Unable to handle] Date: Thu, 15 Sep 2011 14:58:21 -0400 Message-ID: <4E724ACD.1050207@theshore.net> References: <9CAEB881-07FE-437C-8A6B-DB7B690CEABE@linode.com> <4E5BA49D.5060800@theshore.net> <20110829150734.GB24825@dumpdata.com> <1314704744.28989.2.camel@zakaz.uk.xensource.com> <4E5E9CDB.3070706@theshore.net> <20110906171319.GB29839@dumpdata.com> <4E6E2E11.1030602@theshore.net> <20110912161127.GB16100@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110912161127.GB16100@oracle.com> Sender: linux-kernel-owner@vger.kernel.org To: Konrad Rzeszutek Wilk Cc: Ian Campbell , "xen-devel@lists.xensource.com" , LKML , Jeremy Fitzhardinge List-Id: xen-devel@lists.xenproject.org On 9/12/11 12:11 PM, Konrad Rzeszutek Wilk wrote: > On Mon, Sep 12, 2011 at 12:06:41PM -0400, Christopher S. Aker wrote: >>> It would really neat if the issue you have been hitting was exactly this >>> and just having you revert the ef691947d8a3d479e67652312783aedcf629320a >>> would fix it. >> >> Reverted, built, deployed, and set as default. We shall see! > > No joy. Still getting reports even with the patched kernel. I was so confident that this was the problem -- I've tripled checked that the patch was applied and that this is indeed the correct kernel. It was built with DEBUG_HIGHMEM too, without any difference in the dump. BUG: unable to handle kernel paging request at f5768598 IP: [] swap_count_continued+0x84/0x180 *pdpt = 0000000000939027 *pde = 00000000017ef067 *pte = 0000000000000000 Oops: 0000 [#1] SMP Modules linked in: Pid: 1619, comm: apache2 Not tainted 3.0.4-linode37 #1 EIP: 0061:[] EFLAGS: 00010246 CPU: 2 EIP is at swap_count_continued+0x84/0x180 EAX: f5768598 EBX: ed13af80 ECX: ec9cf0a0 EDX: 00000080 ESI: ed1d35a0 EDI: 00000080 EBP: 00000598 ESP: e73d3dd4 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0069 Process apache2 (pid: 1619, ti=e73d2000 task=ebd0e410 task.ti=e73d2000) Stack: ebd3f240 0000e598 00000040 00000000 c01abdc1 ec540e30 ebd3f240 0000e598 00000000 c01ae027 ec540e30 b8fc6000 e73d3e68 c01a00e3 44846045 80000008 00000000 00000020 c0105c27 2bbca063 001cb300 eb424200 ecf7780c eaaade38 Call Trace: [] ? swap_entry_free+0xf1/0x120 [] ? free_swap_and_cache+0x27/0xd0 [] ? zap_pte_range+0x173/0x460 [] ? xen_force_evtchn_callback+0x17/0x30 [] ? unmap_page_range+0x100/0x180 [] ? unmap_vmas+0x8a/0xc0 [] ? exit_mmap+0x73/0x100 [] ? mmput+0x2b/0xc0 [] ? exit_mm+0xef/0x120 [] ? _raw_spin_lock_irq+0x10/0x20 [] ? do_exit+0x125/0x350 [] ? remove_vma+0x37/0x50 [] ? do_group_exit+0x3c/0xa0 [] ? sys_exit_group+0x11/0x20 [] ? syscall_call+0x7/0xb [] ? sctp_err_lookup+0xb0/0x110 Code: 00 00 89 fa 80 fa 80 74 22 e9 0b 01 00 00 90 e8 63 7a f7 ff 8b 5b 18 83 eb 18 39 de 0f 84 f3 00 00 00 89 d8 e8 de 7c f7 ff 01 e8 <0f> b6 10 80 fa 80 74 dc 84 d2 0f 84 e2 00 00 00 83 ea 01 80 fa EIP: [] swap_count_continued+0x84/0x180 SS:ESP 0069:e73d3dd4 CR2: 00000000f5768598 ---[ end trace 06805b7648b253a0 ]--- So today I built a new stack and enabled loglvl=warning and guest_loglvl=warning/info, however it's probably going to take a while before we have enough of these running and hit this problem. I'm going to play around with it some more and see if I can find a recipe that can reproduce. -Chris