From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michal =?iso-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>
Subject: Re: [V2][PATCH] cgroup: fix memory leak caused by missing
 cgroup_bpf_offline
Date: Wed, 20 Oct 2021 19:28:40 +0200
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To: Quanyang Wang <quanyang.wang@windriver.com>
Cc: Ming Lei <ming.lei@redhat.com>, Tejun Heo <tj@kernel.org>, Zefan Li <lizefan.x@bytedance.com>, Johannes Weiner <hannes@cmpxchg.org>, Alexei Starovoitov <ast@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>, Andrii Nakryiko <andrii@kernel.org>, Jens Axboe <axboe@kernel.dk>, Roman Gushchin <guro@fb.com>, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org

On Wed, Oct 20, 2021 at 01:22:06PM +0800, Quanyang Wang <quanyang.wang@windriver.com> wrote:
> > If only precpu_ref data is leaked, it is fine to add "Fixes: 2b0d3d3e4fcf",
> > I thought cgroup_bpf_release() needs to release more for root cgroup, but
> > looks not true.
> For now, I can only observe that precpu_ref data is leaked when running ltp
> testsuite.

I assume you refer to ref->data. I considered the ref->percpu_count_ptr
allocated with __alloc_percpu_gfp(). Could it be that kmemleak won't
detect leaked percpu allocations?

(The patch you sent resolves this as well, I'm just curious.)

Michal