linux-kernel - Re: [-mm patch] Show memcg information during OOM (v3)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <498BA857.3080809@cn.fujitsu.com>
Date:	Fri, 06 Feb 2009 11:02:47 +0800
From:	Li Zefan <lizf@...fujitsu.com>
To:	balbir@...ux.vnet.ibm.com
CC:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"nishimura@....nes.nec.co.jp" <nishimura@....nes.nec.co.jp>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>
Subject: Re: [-mm patch] Show memcg information during OOM (v3)

> +	mem_cgrp = memcg->css.cgroup;
> +	task_cgrp = mem_cgroup_from_task(p)->css.cgroup;

I just noticed since v2, task's cgroup is also printed. Then 2 issues here:

1. this is better: task_cgrp = task_subsys_state(p, mem_cgroup_subsys_id);
2. getting cgroup from a task should be protected by task_lock or rcu_read_lock,
   so we can put the above statement inside rcu_read_lock below.

> +
> +	rcu_read_lock();
> +	ret = cgroup_path(task_cgrp, task_memcg_name, PATH_MAX);
> +	if (ret < 0) {
> +		/*
> +		 * Unfortunately, we are unable to convert to a useful name
> +		 * But we'll still print out the usage information
> +		 */
> +		rcu_read_unlock();
> +		goto done;
> +	}
> +	ret = cgroup_path(mem_cgrp, memcg_name, PATH_MAX);
> +	 if (ret < 0) {
> +		rcu_read_unlock();
> +		goto done;
> +	}
> +
> +	rcu_read_unlock();
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/