linux-kernel - Re: [PATCH v2 0/2] Quieten softlockup detector on virtualised kernels

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 02 Feb 2015 15:58:38 +1100
From:	Cyril Bur <cyrilbur@...il.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	mpe@...erman.id.au, drjones@...hat.com, dzickus@...hat.com,
	linux-kernel@...r.kernel.org, mingo@...nel.org,
	uobergfe@...hat.com, chaiw.fnst@...fujitsu.com, fabf@...net.be,
	atomlin@...hat.com, benzh@...omium.org, schwidefsky@...ibm.com
Subject: Re: [PATCH v2 0/2] Quieten softlockup detector on virtualised
 kernels

Hi Andrew,

Could you please pick these patches up through your tree?

Thanks,

Cyril

On Fri, 2015-01-09 at 14:34 +1100, Cyril Bur wrote:
> When the hypervisor pauses a virtualised kernel the kernel will observe a jump
> in timebase, this can cause spurious messages from the softlockup detector.
> 
> Whilst these messages are harmless, they are accompanied with a stack trace
> which causes undue concern and more problematically the stack trace in the
> guest has nothing to do with the observed problem and can only be misleading.
> 
> Futhermore, on POWER8 this is completely avoidable with the introduction of
> the Virtual Time Base (VTB) register.
> 
> V2:
> 	Remove the export of running_clock
> 	Added #ifdef CONFIG_PPC_PSERIES and optimised the non lpar + vtb cases.
> 	Replaced the use of sched_clock_with local_clock it was used originally in
> the softlockup detector.
> 
> Cyril Bur (2):
>   Add another clock for use with the soft lockup watchdog.
>   powerpc: add running_clock for powerpc to prevent spurious softlockup
>     warnings
> 
>  arch/powerpc/kernel/time.c | 32 ++++++++++++++++++++++++++++++++
>  include/linux/sched.h      |  1 +
>  kernel/sched/clock.c       | 13 +++++++++++++
>  kernel/watchdog.c          |  2 +-
>  4 files changed, 47 insertions(+), 1 deletion(-)
> 


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/