Subject: Re: [vserver] Help me shed some light on a kernel bug
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Tue, 3 Feb 2009 13:24:21 +0100

On Mon, Feb 02, 2009 at 11:44:03PM -0500, Cedric Veilleux wrote:
> Hi,
> 
> I had a server running a vserver patched kernel crash repeatedly (3-4
> times) in a 48 hours period.
> 
> The only error logged was the one pasted below. There was in fact
> sometimes one of these logged, some times many similar ones before a
> crash.
> 
> So, the log output might be misleading as it did not lead immediately to
> a system crash, but everytime it happened, the system would freeze
> eventually.
> 
> What is very special is that this system had 440 days of uptime before
> the first crash. It was running on a Debian Backports kernel labeled
> 2.6.22-6~bpo40+1, with vserver-info showing:
> 
>                    Kernel: 2.6.22-3-vserver-amd64
>                    VS-API: 0x00020200
>              util-vserver: 0.30.216-pre2772; Nov  8 2008, 21:49:08
> 
> 
> So, this might very well not be a vserver related bug at all, but I am
> posting here since people more knowledgeable than me can point me in the
> right direction.
> 
> Also, I would suspect a failing system, maybe some failing system
> memory? But the wording of the error message "Kernel BUG at ..." leads
> me to believe this is a software error and not hardware related...?
> 
> Finally, I since upgraded to 2.6.26-bpo.1-vserver-amd64 and now it has
> been running fine for 4 days with no errors.
> 
> 
> Let me know what you think.
> 
> Thank you
> 
> Cedric
> 
> Jan 28 19:05:19 mtl1 kernel: ------------[ cut here ]------------
> Jan 28 19:05:19 mtl1 kernel: kernel BUG at mm/rmap.c:629!

sounds like bad/unstable memory, I'd give memtest
a longer run (like 6 hours or so) and see if the
memory passes all tests ...

best,
Herbert

> Jan 28 19:05:19 mtl1 kernel: invalid opcode: 0000 [1] SMP 
> Jan 28 19:05:19 mtl1 kernel: CPU 3 
> Jan 28 19:05:19 mtl1 kernel: Modules linked in: generic piix ide_core ata_generic
ata_piix libata ehci_hcd scsi_mod tg3 uhci_hcd thermal processor fan
> Jan 28 19:05:19 mtl1 kernel: Pid: 706:#0, comm: udevd Not tainted 2.6.22-3-vserver-amd64
#1
> Jan 28 19:05:19 mtl1 kernel: RIP: 0010:[<ffffffff8027d383>]  [<ffffffff8027d383>]
page_remove_rmap+0xed/0x109
> Jan 28 19:05:19 mtl1 kernel: RSP: 0018:ffff8101191cfdb8  EFLAGS: 00010246
> Jan 28 19:05:19 mtl1 kernel: RAX: 0000000000000000 RBX: ffff81011fb674a0 RCX: 0000000000004e51
> Jan 28 19:05:19 mtl1 kernel: RDX: 00000000ffffff01 RSI: ffff81011b4048b8 RDI: ffffffff804c3d5c
> Jan 28 19:05:19 mtl1 kernel: RBP: ffff8101196b3348 R08: 000000000000000e R09: 000000007fffffff
> Jan 28 19:05:19 mtl1 kernel: R10: 0000000000000000 R11: ffffffff8031e493 R12: 0000000000517000
> Jan 28 19:05:19 mtl1 kernel: R13: ffff81011b4048b8 R14: ffff810119160f40 R15: 0000000000552000
> Jan 28 19:05:19 mtl1 kernel: FS:  0000000000000000(0000) GS:ffff81011ba10b40(0000)
knlGS:0000000000000000
> Jan 28 19:05:19 mtl1 kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> Jan 28 19:05:19 mtl1 kernel: CR2: 00002b8cfc7fb4c8 CR3: 0000000119aef000 CR4: 00000000000006e0
> Jan 28 19:05:19 mtl1 kernel: Process udevd (pid: 706[#0], threadinfo ffff8101191ce000,
task ffff81011af18140)
> Jan 28 19:05:19 mtl1 kernel: Stack:  000000001ab23020 ffff81011fb674a0 000000000afcc020
ffffffff8027516e
> Jan 28 19:05:19 mtl1 kernel:  0000000000000000 ffff8101191cfea8 ffffffffffffffff 0000000000000000
> Jan 28 19:05:19 mtl1 kernel:  ffff8101196b3348 ffff8101191cfeb0 00000000003e9ffd 0000000000000000
> Jan 28 19:05:19 mtl1 kernel: Call Trace:
> Jan 28 19:05:19 mtl1 kernel:  [<ffffffff8027516e>] unmap_vmas+0x3f9/0x758
> Jan 28 19:05:19 mtl1 kernel:  [<ffffffff8027ad26>] exit_mmap+0x76/0x19c
> Jan 28 19:05:19 mtl1 kernel:  [<ffffffff8022fe34>] mmput+0x2c/0x9d
> Jan 28 19:05:19 mtl1 kernel:  [<ffffffff802356e4>] do_exit+0x222/0x947
> Jan 28 19:05:19 mtl1 kernel:  [<ffffffff80235e88>] sys_exit_group+0x0/0xe
> Jan 28 19:05:19 mtl1 kernel:  [<ffffffff80209d9e>] system_call+0x7e/0x83
> Jan 28 19:05:19 mtl1 kernel: 
> Jan 28 19:05:19 mtl1 kernel: 
> Jan 28 19:05:19 mtl1 kernel: Code: 0f 0b eb fe 8b 77 18 41 58 5b 5d 83 e6 01 f7 de
83 c6 04 e9 
> Jan 28 19:05:19 mtl1 kernel: RIP  [<ffffffff8027d383>] page_remove_rmap+0xed/0x109
> Jan 28 19:05:19 mtl1 kernel:  RSP <ffff8101191cfdb8>
> Jan 28 19:05:19 mtl1 kernel: Fixing recursive fault but reboot is needed!
> 
> 
> 
> 
> 
> 
> 
> -  
> Cédric Veilleux
> Solutions Internet Neopeak inc.
> http://www.neopeak.com/
> 514-906-5847   #252
> 1-866-760-1350 #252
>