From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Fabio Comolli" Subject: Re: [Bug #12155] Regression in 2.6.28-rc and 2.6.27-stable - hibernate related Date: Sat, 13 Dec 2008 19:45:18 +0100 Message-ID: References: Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:cc:in-reply-to:mime-version:content-type :content-transfer-encoding:content-disposition:references; bh=T59B38Db7O/bD40VAk7e7c7loU+hiC8VStvgEPdnaGM=; b=d20Rp51RO3f4jOWwLsjL7DXSGJui+gSdTQvbZvjy4QU44tpL3aENZ4CxVDpvaoKFv/ jv6Snu2G02yf3V2n3wZ8vu//Oa/BOiQMNdqhQ2InLIoUHeG3ANtqLxKxqCAwYBcwr/Lq jCO8G9b8zTsQw0k+ZlE0DeL03qrLShH/PzWY8= In-Reply-To: Content-Disposition: inline Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: "Rafael J. Wysocki" Cc: Linux Kernel Mailing List , Kernel Testers List , Dave Kleikamp Hi. On Sat, Dec 13, 2008 at 5:33 PM, Rafael J. Wysocki 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 > 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 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 Acked-by: Peter Zijlstra Signed-off-by: Ingo Molnar Cc: Chuck Ebbert Signed-off-by: Greg Kroah-Hartman ------------------------------------------------------------------------------------------------------------ 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).