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Date: Tue, 4 Jun 2013 19:32:52 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>,
        Al Viro <viro@ZenIV.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>, Michal Hocko <mhocko@suse.cz>,
        Sergey Dyasly <dserrg@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/4] proc: first_tid() fix/cleanup
Message-ID: <20130604173252.GA22223@redhat.com>
References: <20130603190640.GA11481@redhat.com>
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Andrew,

On 06/03, Oleg Nesterov wrote:
>
> next_thread() should be avoided, probably next_tid() is the
> only "valid" user.
>
> But now we have another reason to avoid (and probably even kill)
> it, we are going to replace or fix while_each_thread(), almost
> every lockless usage is wrong.
>
> Changes:
>
> 	1/4: Update the changelog, do not move the comment.
>
> 	2/4: No changes.

So these two are fine, but please ignore 3 and 4.

> 	3/4: Update the comment following the explanations from
> 	     Eric.
>
> 	     Eric pointed that get_proc_task() without rcu lock
> 	     can trigger the (bogus) warning. Extract the similar
> 	     check from pid_delete_dentry() into the new helper
> 	     and use it instead.
>
> 	     I didn't dare to preserve his ack, but the only change
> 	     is the new proc_inode_is_dead() helper and
>
> 		- if (pid_task(proc_pid(inode))
> 		+ if (proc_inode_is_dead(inode))
>
> 	     in proc_task_readdir().

Looks like a good cleanup and it was acked, but conflicts (textually)
with viro/vfs.git#experimental.

> 	4/4: New.

Should be updated and conflicts too.

Oleg.