From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Eric Paris <eparis@redhat.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>, Ingo Molnar <mingo@elte.hu>,
Peter Zijlstra <peterz@infradead.org>,
Miles Lane <miles.lane@gmail.com>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] RCU: don't turn off lockdep when find suspicious rcu_dereference_check() usage
Date: Tue, 20 Apr 2010 06:28:39 -0700 [thread overview]
Message-ID: <20100420132839.GB2628@linux.vnet.ibm.com> (raw)
In-Reply-To: <1271766716.2972.16.camel@dhcp231-113.rdu.redhat.com>
On Tue, Apr 20, 2010 at 08:31:56AM -0400, Eric Paris wrote:
> On Tue, 2010-04-20 at 16:23 +0800, Lai Jiangshan wrote:
>
> > [PATCH] RCU: don't turn off lockdep when find suspicious rcu_dereference_check() usage
> >
> > When suspicious rcu_dereference_check() usage is detected, lockdep is still
> > available actually, so we should not call debug_locks_off() in
> > lockdep_rcu_dereference().
> >
> > For get rid of too much "suspicious rcu_dereference_check() usage"
> > output when the "if(!debug_locks_off())" statement is removed. This patch uses
> > static variable '__warned's for very usage of "rcu_dereference*()".
> >
> > One variable per usage, so, Now, we can get multiple complaint
> > when we detect multiple different suspicious rcu_dereference_check() usage.
> >
> > Requested-by: Eric Paris <eparis@redhat.com>
> > Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
>
> Although mine was a linux-next kernel and it doesn't appear that I have
> rcu_dereference_protected() at all, so I dropped that bit of the patch,
> it worked great! I got 4 more complaints to harass people with. Feel
> free to add my tested by if you care to.
>
> Tested-by: Eric Paris <eparis@redhat.com>
Very nice!!! Queued for urgent, thank you Lai and Eric!!!
Thanx, Paul
next prev parent reply other threads:[~2010-04-20 13:28 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-08 1:26 INFO: suspicious rcu_dereference_check() usage - include/linux/cgroup.h:492 invoked rcu_dereference_check() without protection! Miles Lane
2010-03-11 3:28 ` Paul E. McKenney
2010-04-12 18:44 ` Eric Paris
2010-04-12 18:47 ` Peter Zijlstra
2010-04-14 10:47 ` Peter Zijlstra
2010-04-15 15:47 ` Paul E. McKenney
2010-04-19 3:45 ` Lai Jiangshan
2010-04-19 18:26 ` Eric Paris
2010-04-19 23:01 ` Paul E. McKenney
2010-04-20 1:25 ` Eric Paris
2010-04-20 3:04 ` Paul E. McKenney
2010-04-20 7:21 ` Peter Zijlstra
2010-04-20 8:23 ` [PATCH] RCU: don't turn off lockdep when find suspicious rcu_dereference_check() usage Lai Jiangshan
2010-04-20 8:36 ` Peter Zijlstra
2010-04-20 12:31 ` Eric Paris
2010-04-20 13:28 ` Paul E. McKenney [this message]
[not found] ` <j2ya44ae5cd1004200545q6be4ec82o18ae99d93e8c29c7@mail.gmail.com>
2010-04-20 13:52 ` Paul E. McKenney
2010-04-20 15:38 ` Miles Lane
2010-04-21 6:04 ` Borislav Petkov
2010-04-21 21:45 ` Paul E. McKenney
2010-04-21 21:35 ` Paul E. McKenney
2010-04-21 21:48 ` Paul E. McKenney
2010-04-21 21:57 ` Eric Dumazet
2010-04-21 22:14 ` Paul E. McKenney
2010-04-21 23:26 ` Eric W. Biederman
2010-04-22 14:56 ` Vivek Goyal
2010-04-22 16:01 ` Paul E. McKenney
2010-04-23 12:50 ` Miles Lane
2010-04-23 19:42 ` Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 01/12] rcu: Fix RCU lockdep splat in set_task_cpu on fork path Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 02/12] rcu: fix RCU lockdep splat on freezer_fork path Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 03/12] rcu: leave lockdep enabled after RCU lockdep splat Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 04/12] NFSv4: Fix the locking in nfs_inode_reclaim_delegation() Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 05/12] NFS: Fix RCU issues in the NFSv4 delegation code Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 06/12] KEYS: Fix an RCU warning Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 07/12] KEYS: Fix an RCU warning in the reading of user keys Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 08/12] cgroup: Fix an RCU warning in cgroup_path() Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 09/12] cgroup: Fix an RCU warning in alloc_css_id() Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 10/12] sched: Fix an RCU warning in print_task() Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 11/12] cgroup: Check task_lock in task_subsys_state() Paul E. McKenney
2010-04-23 19:43 ` [PATCH v2.6.34-rc5 12/12] memcg: css_id() must be called under rcu_read_lock() Paul E. McKenney
2010-04-23 22:59 ` [PATCH] RCU: don't turn off lockdep when find suspicious rcu_dereference_check() usage Miles Lane
2010-04-24 5:35 ` Miles Lane
2010-04-25 2:36 ` Paul E. McKenney
2010-04-25 2:34 ` Paul E. McKenney
2010-04-25 7:45 ` Johannes Berg
2010-04-25 7:49 ` David Miller
2010-04-26 2:07 ` Paul E. McKenney
2010-04-25 15:49 ` Miles Lane
2010-04-25 20:20 ` Miles Lane
2010-04-26 16:09 ` Paul E. McKenney
2010-04-26 18:35 ` Eric W. Biederman
2010-04-27 4:27 ` Paul E. McKenney
2010-04-27 16:22 ` Paul E. McKenney
2010-04-27 16:33 ` Eric Dumazet
2010-04-27 17:58 ` Miles Lane
2010-04-27 23:31 ` Paul E. McKenney
2010-04-27 23:42 ` David Miller
2010-04-27 23:52 ` Paul E. McKenney
[not found] ` <p2ka44ae5cd1004281358n86ce29d2tbece16b2fb974dab@mail.gmail.com>
2010-04-28 21:37 ` Paul E. McKenney
2010-05-01 17:26 ` Miles Lane
2010-05-01 21:55 ` Paul E. McKenney
2010-05-02 2:00 ` Miles Lane
2010-05-02 4:11 ` Paul E. McKenney
2010-04-21 1:05 ` INFO: suspicious rcu_dereference_check() usage - include/linux/cgroup.h:492 invoked rcu_dereference_check() without protection! Li Zefan
2010-04-21 3:14 ` Paul E. McKenney
2010-04-14 16:03 ` Paul E. McKenney
-- strict thread matches above, loose matches on Subject: below --
2010-06-01 13:06 [PATCH] RCU: don't turn off lockdep when find suspicious rcu_dereference_check() usage Daniel J Blueman
2010-06-02 14:56 ` Paul E. McKenney
2010-06-02 15:24 ` Daniel J Blueman
2010-06-03 9:22 ` Li Zefan
2010-06-03 18:30 ` Paul E. McKenney
2010-06-04 2:44 ` Li Zefan
2010-06-04 4:10 ` Paul E. McKenney
2010-06-04 8:54 ` Daniel J Blueman
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=20100420132839.GB2628@linux.vnet.ibm.com \
--to=paulmck@linux.vnet.ibm.com \
--cc=eparis@redhat.com \
--cc=laijs@cn.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=miles.lane@gmail.com \
--cc=mingo@elte.hu \
--cc=peterz@infradead.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox