On Fri 06-04-18 11:54:41, Johannes Weiner wrote:
> On Fri, Apr 06, 2018 at 02:53:30PM +1000, Stephen Rothwell wrote:
> > Hi Andrew,
> >
> > After merging the akpm-current tree, today's linux-next build (x86_64
> > allmodconfig) produced this warning:
> >
> > mm/memcontrol.c: In function 'memory_events_show':
> > mm/memcontrol.c:5453:23: warning: array subscript is above array bounds
> > [-Warray-bounds]
> > atomic_long_read(&memcg->memory_events[OOM_KILL]));
> > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > Introduced by commit
> >
> > 725844c87a0d ("mm: memcg: make sure memory.events is uptodate when waking
> > pollers")
>
> Ah, silly, I missed that warning. The below fixes it.
>
> Signed-off-by: Johannes Weiner <han...@cmpxchg.org>
> ---
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 04ea2b104ee2..9bac6dc26e09 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -5199,8 +5199,7 @@ static int memory_events_show(struct seq_file *m, void
> *v)
> atomic_long_read(&memcg->memory_events[MEMCG_MAX]));
> seq_printf(m, "oom %lu\n",
> atomic_long_read(&memcg->memory_events[MEMCG_OOM]));
> - seq_printf(m, "oom_kill %lu\n",
> - atomic_long_read(&memcg->memory_events[OOM_KILL]));
> + seq_printf(m, "oom_kill %lu\n", memcg_sum_events(memcg, OOM_KILL));
Ohh, this is so easy to miss.
--
Michal Hocko
SUSE Labs
