linux-kernel - Re: TSC not updating after resume: Bug or Feature?

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:	Thu, 18 Dec 2008 23:19:56 +0100
From:	"Rafael J. Wysocki" <rjw@...k.pl>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Peter Zijlstra <peterz@...radead.org>,
	Steven Rostedt <srostedt@...hat.com>, dsaxena@...xity.net,
	Thomas Gleixner <tglx@...utronix.de>,
	linux-kernel@...r.kernel.org,
	Dave Kleikamp <shaggy@...ux.vnet.ibm.com>
Subject: Re: TSC not updating after resume: Bug or Feature?

On Thursday, 18 of December 2008, Ingo Molnar wrote:
> 
> * Peter Zijlstra <peterz@...radead.org> wrote:
> 
> > Rafael, would something like this explain why we had to revert Shaggy's 
> > patch?

Well, I have yet to understand what the suspend-resume of the timekeeping code
actually does.

The original description sounds worrisome to me, it looks like we've overlooked
something at least.

> > His patch fixes the backward motion filter and I'm at an utter  
> > loss why that would break suspend.
> 
> yes, i'd love to have this commit reinstated:
> 
>  5b7dba4: sched_clock: prevent scd->clock from moving backwards
> 
> and the bug triggered by hibernation fixed instead.

Shaggy said he had an idea of what was wrong, so I expect an updated version
of the patch to appear.

Thanks,
Rafael
--
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/