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* [PATCH 2/9] memcg: accounting for fib6_nodes cache
@ 2021-03-09  8:03 Vasily Averin
  2021-03-09 21:16 ` Shakeel Butt
  0 siblings, 1 reply; 3+ messages in thread
From: Vasily Averin @ 2021-03-09  8:03 UTC (permalink / raw)
  To: cgroups, linux-mm; +Cc: Johannes Weiner, Michal Hocko, Vladimir Davydov

Objects can be created from memcg-limited tasks
but its misuse may lead to host OOM.

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
---
 net/ipv6/ip6_fib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index ef9d022..fa92ed1 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -2445,7 +2445,7 @@ int __init fib6_init(void)
 
 	fib6_node_kmem = kmem_cache_create("fib6_nodes",
 					   sizeof(struct fib6_node),
-					   0, SLAB_HWCACHE_ALIGN,
+					   0, SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT,
 					   NULL);
 	if (!fib6_node_kmem)
 		goto out;
-- 
1.8.3.1



^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH 2/9] memcg: accounting for fib6_nodes cache
  2021-03-09  8:03 [PATCH 2/9] memcg: accounting for fib6_nodes cache Vasily Averin
@ 2021-03-09 21:16 ` Shakeel Butt
  2021-03-10  0:13   ` Roman Gushchin
  0 siblings, 1 reply; 3+ messages in thread
From: Shakeel Butt @ 2021-03-09 21:16 UTC (permalink / raw)
  To: Vasily Averin
  Cc: Cgroups, Linux MM, Johannes Weiner, Michal Hocko, Vladimir Davydov

On Tue, Mar 9, 2021 at 12:04 AM Vasily Averin <vvs@virtuozzo.com> wrote:
>
> Objects can be created from memcg-limited tasks
> but its misuse may lead to host OOM.
>
> Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
> ---
>  net/ipv6/ip6_fib.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
> index ef9d022..fa92ed1 100644
> --- a/net/ipv6/ip6_fib.c
> +++ b/net/ipv6/ip6_fib.c
> @@ -2445,7 +2445,7 @@ int __init fib6_init(void)
>
>         fib6_node_kmem = kmem_cache_create("fib6_nodes",

Can you talk a bit more about the lifetime of the object created from
this kmem cache? Also who and what operation can trigger allocation?

Similarly can you add this information to the remaining patches of
your series as well?

>                                            sizeof(struct fib6_node),
> -                                          0, SLAB_HWCACHE_ALIGN,
> +                                          0, SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT,
>                                            NULL);
>         if (!fib6_node_kmem)
>                 goto out;
> --
> 1.8.3.1
>


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH 2/9] memcg: accounting for fib6_nodes cache
  2021-03-09 21:16 ` Shakeel Butt
@ 2021-03-10  0:13   ` Roman Gushchin
  0 siblings, 0 replies; 3+ messages in thread
From: Roman Gushchin @ 2021-03-10  0:13 UTC (permalink / raw)
  To: Shakeel Butt
  Cc: Vasily Averin, Cgroups, Linux MM, Johannes Weiner, Michal Hocko,
	Vladimir Davydov

On Tue, Mar 09, 2021 at 01:16:13PM -0800, Shakeel Butt wrote:
> On Tue, Mar 9, 2021 at 12:04 AM Vasily Averin <vvs@virtuozzo.com> wrote:
> >
> > Objects can be created from memcg-limited tasks
> > but its misuse may lead to host OOM.
> >
> > Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
> > ---
> >  net/ipv6/ip6_fib.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
> > index ef9d022..fa92ed1 100644
> > --- a/net/ipv6/ip6_fib.c
> > +++ b/net/ipv6/ip6_fib.c
> > @@ -2445,7 +2445,7 @@ int __init fib6_init(void)
> >
> >         fib6_node_kmem = kmem_cache_create("fib6_nodes",
> 
> Can you talk a bit more about the lifetime of the object created from
> this kmem cache? Also who and what operation can trigger allocation?

The lifetime is less of a concern since we have a slab reparenting mechanism,
unless it's a very short-living object.


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-03-10  0:14 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2021-03-09  8:03 [PATCH 2/9] memcg: accounting for fib6_nodes cache Vasily Averin
2021-03-09 21:16 ` Shakeel Butt
2021-03-10  0:13   ` Roman Gushchin

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