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From: Michal Hocko <mhocko@kernel.org>
To: Yizhuo Zhai <yzhai003@ucr.edu>
Cc: Chengyu Song <csong@cs.ucr.edu>, Zhiyun Qian <zhiyunq@cs.ucr.edu>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Vladimir Davydov <vdavydov.dev@gmail.com>,
	cgroups@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/memcg: return value of the function mem_cgroup_from_css() is not checked
Date: Thu, 22 Aug 2019 22:12:00 +0200	[thread overview]
Message-ID: <20190822201200.GP12785@dhcp22.suse.cz> (raw)
In-Reply-To: <CABvMjLRCt4gC3GKzBehGppxfyMOb6OGQwW-6Yu_+MbMp5tN3tg@mail.gmail.com>

On Thu 22-08-19 13:07:17, Yizhuo Zhai wrote:
> This will happen if variable "wb->memcg_css" is NULL. This case is reported
> by our analysis tool.

Does your tool report the particular call path and conditions when that
happen? Or is it just a "it mignt happen" kinda thing?

> Since the function mem_cgroup_wb_domain() is visible to the global, we
> cannot control caller's behavior.

I am sorry but I do not understand what is this supposed to mean.
-- 
Michal Hocko
SUSE Labs

  parent reply	other threads:[~2019-08-22 20:12 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-22  6:22 [PATCH] mm/memcg: return value of the function mem_cgroup_from_css() is not checked Yizhuo
2019-08-22  7:05 ` Michal Hocko
     [not found]   ` <CABvMjLRCt4gC3GKzBehGppxfyMOb6OGQwW-6Yu_+MbMp5tN3tg@mail.gmail.com>
2019-08-22 20:12     ` Michal Hocko [this message]
2019-08-30 22:27       ` Yizhuo Zhai

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