linux-kernel - Re: [PATCH 0/5] Candidate fix for increased number of GFP

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, 22 Oct 2009 17:47:10 +0300
From:	Pekka Enberg <penberg@...helsinki.fi>
To:	Mel Gorman <mel@....ul.ie>
Cc:	Frans Pop <elendil@...net.nl>, Jiri Kosina <jkosina@...e.cz>,
	Sven Geggus <lists@...hsschwanzdomain.de>,
	Karol Lewandowski <karol.k.lewandowski@...il.com>,
	Tobias Oetiker <tobi@...iker.ch>,
	"Rafael J. Wysocki" <rjw@...k.pl>,
	David Miller <davem@...emloft.net>,
	Reinette Chatre <reinette.chatre@...el.com>,
	Kalle Valo <kalle.valo@....fi>,
	David Rientjes <rientjes@...gle.com>,
	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Mohamed Abbas <mohamed.abbas@...el.com>,
	Jens Axboe <jens.axboe@...cle.com>,
	"John W. Linville" <linville@...driver.com>,
	Bartlomiej Zolnierkiewicz <bzolnier@...il.com>,
	Greg Kroah-Hartman <gregkh@...e.de>,
	Stephan von Krawczynski <skraw@...net.com>,
	Kernel Testers List <kernel-testers@...r.kernel.org>,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
	"linux-mm@...ck.org\"" <linux-mm@...ck.org>,
	akpm@...ux-foundation.org, cl@...ux-foundation.org,
	torvalds@...ux-foundation.org
Subject: Re: [PATCH 0/5] Candidate fix for increased number of GFP_ATOMIC 
	failures V2

On Thu, Oct 22, 2009 at 5:22 PM, Mel Gorman <mel@....ul.ie> wrote:
> Test 1: Verify your problem occurs on 2.6.32-rc5 if you can
>
> Test 2: Apply the following two patches and test again
>
>  1/5 page allocator: Always wake kswapd when restarting an allocation attempt after direct reclaim failed
>  2/5 page allocator: Do not allow interrupts to use ALLOC_HARDER

These are pretty obvious bug fixes and should go to linux-next ASAP IMHO.

> Test 5: If things are still screwed, apply the following
>  5/5 Revert 373c0a7e, 8aa7e847: Fix congestion_wait() sync/async vs read/write confusion
>
>        Frans Pop reports that the bulk of his problems go away when this
>        patch is reverted on 2.6.31. There has been some confusion on why
>        exactly this patch was wrong but apparently the conversion was not
>        complete and further work was required. It's unknown if all the
>        necessary work exists in 2.6.31-rc5 or not. If there are still
>        allocation failures and applying this patch fixes the problem,
>        there are still snags that need to be ironed out.

As explained by Jens Axboe, this changes timing but is not the source
of the OOMs so the revert is bogus even if it "helps" on some
workloads. IIRC the person who reported the revert to help things did
report that the OOMs did not go away, they were simply harder to
trigger with the revert.
--
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/