Re: [PATCH] mm: kmem: make mem_cgroup_from_obj() vmalloc()-safe

From: Vasily Averin
Date: Sat Jun 11 2022 - 00:10:16 EST


On 6/10/22 21:10, Roman Gushchin wrote:
> On Fri, Jun 10, 2022 at 11:03:10AM -0700, Roman Gushchin wrote:
>> Currently mem_cgroup_from_obj() is not working properly with objects
>> allocated using vmalloc(). It creates problems in some cases, when
>> it's called for static objects belonging to modules or generally
>> allocated using vmalloc().
>>
>> This patch makes mem_cgroup_from_obj() safe to be called on objects
>> allocated using vmalloc().
>>
>> It also introduces mem_cgroup_from_slab_obj(), which is a faster
>> version to use in places when we know the object is either a slab
>> object or a generic slab page (e.g. when adding an object to a lru
>> list).
>>
>> Suggested-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
>> Signed-off-by: Roman Gushchin <roman.gushchin@xxxxxxxxx>
>> Tested-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
>> Acked-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
>
> Andrew,
>
> this patch is supposed to fix boot issues on arm introduced by
> the commit "net: set proper memcg for net_init hooks allocations".
>
> But as no I don't see this commit in linux-next or any mm branches,
> so I'm not sure if it's in stable or not. So I didn't add the Fixes
> tag. If it isn't in stable yet, I'd just put the fix before the problematic
> commit.

Roman,
Andrew dropped "net: set proper memcg for net_init hooks allocations" few days ago,
but I hope he will re-apply it again after your patch.
Thank you very much for your help!

Vasily Averin