Re: [x86/MCE] 81aa021b8c: WARNING: CPU: 0 PID: 0 at arch/x86/kernel/cpu/mcheck/mce.c:716 machine_check_poll+0x66/0x21c
From: Borislav Petkov
Date: Thu Nov 10 2016 - 07:46:40 EST
On Thu, Nov 10, 2016 at 08:36:02PM +0800, kernel test robot wrote:
> FYI, we noticed the following commit:
>
> https://github.com/0day-ci/linux Borislav-Petkov/x86-MCE-Correct-TSC-timestamping-of-error-records/20161110-021431
> commit 81aa021b8c6f464b68c6e6df93e64ffe2c2adda6 ("x86/MCE: Remove MCP_TIMESTAMP")
>
> in testcase: boot
>
> on test machine: qemu-system-x86_64 -enable-kvm -m 320M
>
> caused below changes:
>
>
> +-----------------------------------------------------------------+------------+------------+
> | | b2eca63145 | 81aa021b8c |
> +-----------------------------------------------------------------+------------+------------+
> | boot_successes | 16 | 0 |
> | boot_failures | 0 | 10 |
> | WARNING:at_arch/x86/kernel/cpu/mcheck/mce.c:#machine_check_poll | 0 | 10 |
> +-----------------------------------------------------------------+------------+------------+
>
>
>
> [ 0.238462] Mountpoint-cache hash table entries: 1024 (order: 1, 8192 bytes)
> [ 0.240536] mce: CPU supports 10 MCE banks
> [ 0.241403] ------------[ cut here ]------------
> [ 0.242334] WARNING: CPU: 0 PID: 0 at arch/x86/kernel/cpu/mcheck/mce.c:716 machine_check_poll+0x66/0x21c
> [ 0.244554] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.0-rc4-00300-g81aa021 #64
> [ 0.246089] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
> [ 0.247857] Call Trace:
> [ 0.248341] dump_stack+0x61/0x7e
> [ 0.249018] __warn+0xb3/0xce
> [ 0.249594] warn_slowpath_null+0x18/0x1a
Thanks guys, this actually helps!
I'll remove the WARN_ON_ONCE as it confirms a theory we had.
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.