From: John Stultz <john.stultz@linaro.org>
To: Joe Perches <joe@perches.com>
Cc: Jiri Slaby <jirislaby@gmail.com>,
LKML <linux-kernel@vger.kernel.org>, Ted Ts'o <tytso@mit.edu>,
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
David Rientjes <rientjes@google.com>,
Dave Hansen <dave@linux.vnet.ibm.com>,
Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org
Subject: Re: [PATCH 2/3] printk: Add %ptc to safely print a task's comm
Date: Mon, 16 May 2011 17:11:43 -0700 [thread overview]
Message-ID: <1305591103.2915.70.camel@work-vm> (raw)
In-Reply-To: <1305590200.2503.48.camel@Joe-Laptop>
On Mon, 2011-05-16 at 16:56 -0700, Joe Perches wrote:
> On Mon, 2011-05-16 at 16:10 -0700, John Stultz wrote:
> > On Mon, 2011-05-16 at 23:54 +0200, Jiri Slaby wrote:
> > > > In my attempt to clean up unprotected comm access, I've noticed
> > > > most comm access is done for printk output. To simplify correct
> > > > locking in these cases, I've introduced a new %ptc format,
> > > > which will print the corresponding task's comm.
> > > > Example use:
> > > > printk("%ptc: unaligned epc - sending SIGBUS.\n", current);
> > > > diff --git a/lib/vsprintf.c b/lib/vsprintf.c
> []
> > > > +static noinline_for_stack
> > > Actually, why noinline? Did your previous version have there some
> > > TASK_COMM_LEN buffer or anything on stack which is not there anymore?
> > No, I was just following how almost all of the pointer() called
> > functions were declared.
> > But with two pointers and a long, I add more then ip6_string() has on
> > the stack, which uses the same notation.
> > But I can drop that bit if there's really no need for it.
>
> vsprintf can be recursive, I think you should keep it.
Ok. I'll keep it then. Thanks!
-john
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next prev parent reply other threads:[~2011-05-17 0:11 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-16 21:19 [PATCH 0/3] v4 Improve task->comm locking situation John Stultz
2011-05-16 21:19 ` [PATCH 1/3] comm: Introduce comm_lock seqlock to protect task->comm access John Stultz
2011-05-16 22:01 ` Jiri Slaby
2011-05-17 1:47 ` John Stultz
2011-05-18 0:28 ` KOSAKI Motohiro
2011-05-16 21:19 ` [PATCH 2/3] printk: Add %ptc to safely print a task's comm John Stultz
2011-05-16 21:54 ` Jiri Slaby
2011-05-16 23:10 ` John Stultz
2011-05-16 23:56 ` Joe Perches
2011-05-17 0:11 ` John Stultz [this message]
2011-05-17 7:21 ` Jiri Slaby
2011-05-18 0:32 ` KOSAKI Motohiro
2011-05-16 21:19 ` [PATCH 3/3] checkpatch.pl: Add check for task comm references John Stultz
2011-05-16 21:29 ` Michal Nazarewicz
2011-05-16 21:34 ` David Rientjes
2011-05-16 23:04 ` Joe Perches
2011-05-16 23:11 ` Michal Nazarewicz
2011-05-16 23:22 ` Joe Perches
-- strict thread matches above, loose matches on Subject: below --
2011-05-17 20:47 [PATCH 0/3] v5 Improve task->comm locking situation John Stultz
2011-05-17 20:47 ` [PATCH 2/3] printk: Add %ptc to safely print a task's comm John Stultz
2011-05-17 21:42 ` Jiri Slaby
2011-05-17 21:52 ` Joe Perches
2011-05-17 22:04 ` Jiri Slaby
2011-05-17 22:17 ` Joe Perches
2011-05-17 22:17 ` John Stultz
2011-05-12 23:02 [PATCH 0/3] v3 Improve task->comm locking situation John Stultz
2011-05-12 23:02 ` [PATCH 2/3] printk: Add %ptc to safely print a task's comm John Stultz
2011-05-11 0:23 [RFC][PATCH 0/3] v2 Improve task->comm locking situation John Stultz
2011-05-11 0:23 ` [PATCH 2/3] printk: Add %ptc to safely print a task's comm John Stultz
2011-05-11 0:51 ` Joe Perches
2011-05-11 1:10 ` John Stultz
2011-05-11 1:16 ` john stultz
2011-05-11 1:20 ` Joe Perches
2011-05-12 22:12 ` David Rientjes
2011-05-12 22:29 ` Joe Perches
2011-05-13 21:56 ` David Rientjes
2011-05-12 22:10 ` David Rientjes
2011-05-11 9:33 ` Américo Wang
2011-05-11 21:02 ` John Stultz
2011-05-12 10:43 ` Américo Wang
2011-05-12 10:45 ` Américo Wang
2011-05-12 18:01 ` John Stultz
2011-05-11 17:36 ` Andi Kleen
2011-05-11 21:04 ` John Stultz
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