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Date:   Sat, 11 Jun 2022 07:10:06 +0300
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Subject: Re: [PATCH] mm: kmem: make mem_cgroup_from_obj() vmalloc()-safe
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To:     Roman Gushchin <roman.gushchin@linux.dev>,
        Andrew Morton <akpm@linux-foundation.org>
Cc:     linux-kernel@vger.kernel.org,
        Naresh Kamboju <naresh.kamboju@linaro.org>,
        Qian Cai <quic_qiancai@quicinc.com>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Linux Kernel Functional Testing <lkft@linaro.org>,
        Shakeel Butt <shakeelb@google.com>
References: <20220610180310.1725111-1-roman.gushchin@linux.dev>
 <YqOJBy2kHRJj/uLB@carbon>
From:   Vasily Averin <vvs@openvz.org>
In-Reply-To: <YqOJBy2kHRJj/uLB@carbon>
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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@huawei.com>
>> Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
>> Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
>> Acked-by: Shakeel Butt <shakeelb@google.com>
> 
> 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