linux-kernel - Re: [Bug #12155] Regression in 2.6.28-rc and 2.6.27-stable

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:	Sat, 13 Dec 2008 19:45:18 +0100
From:	"Fabio Comolli" <fabio.comolli@...il.com>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
Cc:	"Linux Kernel Mailing List" <linux-kernel@...r.kernel.org>,
	"Kernel Testers List" <kernel-testers@...r.kernel.org>,
	"Dave Kleikamp" <shaggy@...ux.vnet.ibm.com>
Subject: Re: [Bug #12155] Regression in 2.6.28-rc and 2.6.27-stable - hibernate related

Hi.

On Sat, Dec 13, 2008 at 5:33 PM, Rafael J. Wysocki <rjw@...k.pl> wrote:
> This message has been generated automatically as a part of a report
> of recent regressions.
>
> The following bug entry is on the current list of known regressions
> from 2.6.27.  Please verify if it still should be listed and let me know
> (either way).
>
>
> Bug-Entry       : http://bugzilla.kernel.org/show_bug.cgi?id=12155
> Subject         : Regression in 2.6.28-rc and 2.6.27-stable - hibernate related
> Submitter       : Fabio Comolli <fabio.comolli@...il.com>
> Date            : 2008-11-23 16:17 (21 days old)
> References      : http://marc.info/?l=linux-kernel&m=122745709926361&w=4

Still present. It has been bisected to:

---------------------------------------------------------------------------------------------------------------
commit 5e55aa8db085dad1aabb4574c73c23c7ae571e7b
Author: Dave Kleikamp <shaggy@...ux.vnet.ibm.com>
Date:   Sun Oct 26 18:20:14 2008 -0400

    sched_clock: prevent scd->clock from moving backwards

    commit 5b7dba4ff834259a5623e03a565748704a8fe449 upstream

    sched_clock: prevent scd->clock from moving backwards

    When sched_clock_cpu() couples the clocks between two cpus, it may
    increment scd->clock beyond the GTOD tick window that __update_sched_clock()
    uses to clamp the clock.  A later call to __update_sched_clock() may move
    the clock back to scd->tick_gtod + TICK_NSEC, violating the clock's
    monotonic property.

    This patch ensures that scd->clock will not be set backward.

    Signed-off-by: Dave Kleikamp <shaggy@...ux.vnet.ibm.com>
    Acked-by: Peter Zijlstra <a.p.zijlstra@...llo.nl>
    Signed-off-by: Ingo Molnar <mingo@...e.hu>
    Cc: Chuck Ebbert <cebbert@...hat.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>
------------------------------------------------------------------------------------------------------------

Both 2.6.27.8 and 2.6.28-rc8 with that commit reverted work fine
(well, at least they failed to show the bug so far).
--
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/