linux-kernel - Re: [PATCH -mm] vmscan: fix sane_reclaim helper for legacy memcg

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]

Message-ID: <20150918140857.GA17606@dhcp22.suse.cz>
Date:	Fri, 18 Sep 2015 16:08:57 +0200
From:	Michal Hocko <mhocko@...nel.org>
To:	Vladimir Davydov <vdavydov@...allels.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Johannes Weiner <hannes@...xchg.org>,
	Tejun Heo <tj@...nel.org>, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH -mm] vmscan: fix sane_reclaim helper for legacy memcg

On Fri 18-09-15 15:48:00, Vladimir Davydov wrote:
> The sane_reclaim() helper is supposed to return false for memcg reclaim
> if the legacy hierarchy is used, because the latter lacks dirty
> throttling mechanism, and so it did before it was accidentally broken by
> commit 33398cf2f360c ("memcg: export struct mem_cgroup"). Fix it.
> 
> Fixes: 33398cf2f360c ("memcg: export struct mem_cgroup")
> Signed-off-by: Vladimir Davydov <vdavydov@...allels.com>

Acked-by: Michal Hocko <mhocko@...e.com>

Thanks for catching this up!

> ---
>  mm/vmscan.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index db5339dd4a32..dbc3b3ae48de 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -175,7 +175,7 @@ static bool sane_reclaim(struct scan_control *sc)
>  	if (!memcg)
>  		return true;
>  #ifdef CONFIG_CGROUP_WRITEBACK
> -	if (memcg->css.cgroup)
> +	if (cgroup_on_dfl(memcg->css.cgroup))
>  		return true;
>  #endif
>  	return false;
> -- 
> 2.1.4

-- 
Michal Hocko
SUSE Labs
--
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/