All of lore.kernel.org
 help / color / mirror / Atom feed
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
Date: Tue, 4 Jun 2013 19:32:52 +0200	[thread overview]
Message-ID: <20130604173252.GA22223@redhat.com> (raw)
In-Reply-To: <20130603190640.GA11481@redhat.com>

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.


      parent reply	other threads:[~2013-06-04 17:36 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-03 19:06 [PATCH v2 0/4] proc: first_tid() fix/cleanup Oleg Nesterov
2013-06-03 19:06 ` [PATCH v2 1/4] proc: first_tid: fix the potential use-after-free Oleg Nesterov
2013-06-03 19:07 ` [PATCH v2 2/4] proc: change first_tid() to use while_each_thread() Oleg Nesterov
2013-06-03 19:07 ` [PATCH v2 3/4] proc: simplify proc_task_readdir/first_tid paths Oleg Nesterov
2013-06-03 22:06   ` Eric W. Biederman
2013-06-03 19:07 ` [PATCH v2 4/4] proc: avoid ->f_pos overflows in proc_task_readdir() paths Oleg Nesterov
2013-06-03 22:18   ` Eric W. Biederman
2013-06-04 17:14     ` Oleg Nesterov
2013-06-04 17:39       ` Al Viro
2013-06-04 19:57         ` Oleg Nesterov
2013-06-04 21:06           ` Al Viro
2013-06-04  0:58   ` Al Viro
2013-06-04 17:35     ` Oleg Nesterov
2013-06-04 17:32 ` Oleg Nesterov [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20130604173252.GA22223@redhat.com \
    --to=oleg@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=dserrg@gmail.com \
    --cc=ebiederm@xmission.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mhocko@suse.cz \
    --cc=viro@ZenIV.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.