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Date:   Tue, 4 Feb 2020 12:13:07 +0100
From:   Christian Brauner <christian.brauner@ubuntu.com>
To:     Michal =?utf-8?Q?Koutn=C3=BD?= <mkoutny@suse.com>
Cc:     linux-api@vger.kernel.org, linux-kernel@vger.kernel.org,
        Tejun Heo <tj@kernel.org>, Oleg Nesterov <oleg@redhat.com>,
        Ingo Molnar <mingo@redhat.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Li Zefan <lizefan@huawei.com>,
        Peter Zijlstra <peterz@infradead.org>, cgroups@vger.kernel.org
Subject: Re: [PATCH v5 5/6] clone3: allow spawning processes into cgroups
Message-ID: <20200204111307.hxtundpcneju2y7n@wittgenstein>
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On Mon, Feb 03, 2020 at 03:32:28PM +0100, Michal Koutný wrote:
> On Sun, Feb 02, 2020 at 10:37:02AM +0100, Christian Brauner <christian.brauner@ubuntu.com> wrote:
> > cgroup_post_fork() is called past the point of no return for fork and
> > cgroup_css_set_put_fork() is explicitly documented as only being
> > callable before forks point of no return:
> I missed this and somehow incorrectly assumed it's called at the end of
> fork too. I find the css_set refcounting correct now.
> 
> BTW any reason why not to utilize cgroup_css_set_put_fork() for the
> regular cleanup in cgroup_post_fork() too?

Hmyeah, should be doable if we do:
kargs->cset = NULL;
cgroup_css_set_put_fork(kargs);

Christian