Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Fri, 10 Jun 2022 11:10:15 -0700
From:   Roman Gushchin <roman.gushchin@linux.dev>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     linux-kernel@vger.kernel.org,
        Naresh Kamboju <naresh.kamboju@linaro.org>,
        Vasily Averin <vvs@openvz.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>
Subject: Re: [PATCH] mm: kmem: make mem_cgroup_from_obj() vmalloc()-safe
Message-ID: <YqOJBy2kHRJj/uLB@carbon>
References: <20220610180310.1725111-1-roman.gushchin@linux.dev>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20220610180310.1725111-1-roman.gushchin@linux.dev>
Precedence: bulk

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.

Thank you!