From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Subject: Re: [PATCH] memcg: do not expose uninitialized mem_cgroup_per_node to world Date: Wed, 27 Jul 2011 09:58:45 +0200 Message-ID: <20110727075845.GA4024__28599.5830935009$1311753674$gmane$org@tiehlicka.suse.cz> References: <20110601152039.GG4266@tiehlicka.suse.cz> <4DE66BEB.7040502@redhat.com> <4DE8D50F.1090406@redhat.com> <4DEE26E7.2060201@redhat.com> <20110608123527.479e6991.kamezawa.hiroyu@jp.fujitsu.com> <20110608140951.115ab1dd.akpm@linux-foundation.org> <4DF24D04.1080802@redhat.com> <20110726141754.c69b96c6.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20110726141754.c69b96c6.akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Andrew Morton Cc: Tim Deegan , containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Igor Mammedov , Paul Menage , Hiroyuki Kamezawa , balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org List-Id: containers.vger.kernel.org On Tue 26-07-11 14:17:54, Andrew Morton wrote: > On Fri, 10 Jun 2011 18:57:40 +0200 > Igor Mammedov wrote: > > > On 06/08/2011 11:09 PM, Andrew Morton wrote: > > > The original patch: > > > > > > --- a/mm/memcontrol.c > > > +++ b/mm/memcontrol.c > > > @@ -4707,7 +4707,6 @@ static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) > > > if (!pn) > > > return 1; > > > > > > - mem->info.nodeinfo[node] = pn; > > > for (zone = 0; zone< MAX_NR_ZONES; zone++) { > > > mz =&pn->zoneinfo[zone]; > > > for_each_lru(l) > > > @@ -4716,6 +4715,7 @@ static int alloc_mem_cgroup_per_zone_info(struct mem_cgroup *mem, int node) > > > mz->on_tree = false; > > > mz->mem = mem; > > > } > > > + mem->info.nodeinfo[node] = pn; > > > return 0; > > > } > > > > > > looks like a really good idea. But it needs a new changelog and I'd be > > > a bit reluctant to merge it as it appears that the aptch removes our > > > only known way of reproducing a bug. > > > > > > So for now I think I'll queue the patch up unchangelogged so the issue > > > doesn't get forgotten about. > > > > > Problem was in rhel's xen hv. > > It was missing fix for imul emulation. > > Details here > > http://lists.xensource.com/archives/html/xen-devel/2011-06/msg00801.html > > Thanks to Tim Deegan and everyone who was involved in the discussion. > > I really don't want to trawl through a lengthy xen bug report The bug turned out to be Xen specific and this patch just hidden the bug in Xen. > and write your changelog for you. > > We still have no changelog for this patch. Please send one. Appart from a better programming style is there any other reason for taking it? If applied it might hide potential bugs when somebody is touching data too early. -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic