On 4/23/21 5:30 AM, Roman Gushchin wrote: > On Fri, Apr 23, 2021 at 05:09:01AM +0300, Vasily Averin wrote: >> On 4/23/21 4:00 AM, Roman Gushchin wrote: >>> On Thu, Apr 22, 2021 at 08:44:15AM +0300, Vasily Averin wrote: >>>> init_pid_ns.pid_cachep have enabled memcg accounting, though this >>>> setting was disabled for nested pid namespaces. >>>> >>>> Signed-off-by: Vasily Averin <vvs@xxxxxxxxxxxxx> >>>> --- >>>> kernel/pid_namespace.c | 3 ++- >>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c >>>> index 6cd6715..a46a372 100644 >>>> --- a/kernel/pid_namespace.c >>>> +++ b/kernel/pid_namespace.c >>>> @@ -51,7 +51,8 @@ static struct kmem_cache *create_pid_cachep(unsigned int level) >>>> mutex_lock(&pid_caches_mutex); >>>> /* Name collision forces to do allocation under mutex. */ >>>> if (!*pkc) >>>> - *pkc = kmem_cache_create(name, len, 0, SLAB_HWCACHE_ALIGN, 0); >>>> + *pkc = kmem_cache_create(name, len, 0, >>>> + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, 0); >>>> mutex_unlock(&pid_caches_mutex); >>>> /* current can fail, but someone else can succeed. */ >>>> return READ_ONCE(*pkc); >>>> -- >>>> 1.8.3.1 >>>> >>> >>> It looks good to me! It makes total sense to apply the same rules to the root >>> and non-root levels. >>> >>> Acked-by: Roman Gushchin <guro@xxxxxx> >>> >>> Btw, is there any reason why this patch is not included into the series? >> >> It is a bugfix and I think it should be added to upstream ASAP. > > Then it would be really useful to add some details on why it's a bug, > what kind of problems it causes, etc. If it has to be backported to > stable, please, add cc stable/fixes tag. I mean, in this case we already decided to account pids, but forget to do it. In another cases we did not have final decision about accounting. I doubt we specially denied accounting for pids frem nested pid namespaces, especially because they consumes more memory. We can expect that all pids are accounted -- but it does not happen in fact.
