linux-kernel - Re: [PATCH 0/9] perf/x86: implement HT counter corruption workaround

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, 5 Jun 2014 14:45:29 +0200
From:	Stephane Eranian <eranian@...gle.com>
To:	Andi Kleen <ak@...ux.intel.com>
Cc:	LKML <linux-kernel@...r.kernel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	"mingo@...e.hu" <mingo@...e.hu>, Jiri Olsa <jolsa@...hat.com>,
	"Yan, Zheng" <zheng.z.yan@...el.com>,
	Maria Dimakopoulou <maria.n.dimakopoulou@...il.com>
Subject: Re: [PATCH 0/9] perf/x86: implement HT counter corruption workaround

On Thu, Jun 5, 2014 at 12:28 AM, Andi Kleen <ak@...ux.intel.com> wrote:
>> There is no HW or FW workaround for this problem.
>
> Actually there is for global measurements:
>
> measure with Any bit set and divide by two.
>
> Please add a check that the any bit is set, and disable
> the workaround for that case.
>
I think this assume same event is measured on sibling counters at any time.
Otherwise, how does that eliminate the corruption?
--
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/