From: Tejun Heo <tj@kernel.org>
To: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
linux-kernel@vger.kernel.org,
"David S. Miller" <davem@davemloft.net>,
Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
yrl.pp-manager.tt@hitachi.com
Subject: Re: [PATCH -tip ] [BUGFIX] kprobes: Fix a double lock bug of kprobe_mutex
Date: Thu, 18 Apr 2013 11:17:09 -0700 [thread overview]
Message-ID: <20130418181709.GE9897@mtj.dyndns.org> (raw)
In-Reply-To: <20130418093318.13070.29847.stgit@mhiramat-M0-7522>
On Thu, Apr 18, 2013 at 06:33:18PM +0900, Masami Hiramatsu wrote:
> Fix a double locking bug caused when debug.kprobe-optimization=0.
> While the proc_kprobes_optimization_handler locks kprobe_mutex,
> wait_for_kprobe_optimizer locks it again and that causes a double lock.
> To fix the bug, this introduces different mutex for protecting
> sysctl parameter and locks it in proc_kprobes_optimization_handler.
> Of course, since we need to lock kprobe_mutex when touching kprobes
> resources, that is done in *optimize_all_kprobes().
>
> This bug was from ad72b3bea744b4db01c89af0f86f3e8920d354df
>
> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Tejun Heo <tj@kernel.org>
> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
> Cc: "David S. Miller" <davem@davemloft.net>
Oops,
Acked-by: Tejun Heo <tj@kernel.org>
Thanks.
--
tejun
next prev parent reply other threads:[~2013-04-18 18:17 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-18 9:33 [PATCH -tip ] [BUGFIX] kprobes: Fix a double lock bug of kprobe_mutex Masami Hiramatsu
2013-04-18 15:49 ` Ananth N Mavinakayanahalli
2013-04-18 18:17 ` Tejun Heo [this message]
2013-04-19 7:22 ` Ingo Molnar
2013-04-19 7:25 ` Ingo Molnar
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=20130418181709.GE9897@mtj.dyndns.org \
--to=tj@kernel.org \
--cc=ananth@in.ibm.com \
--cc=davem@davemloft.net \
--cc=linux-kernel@vger.kernel.org \
--cc=masami.hiramatsu.pt@hitachi.com \
--cc=mingo@redhat.com \
--cc=torvalds@linux-foundation.org \
--cc=yrl.pp-manager.tt@hitachi.com \
/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