From: Arjan van de Ven <arjan@infradead.org>
To: Tim Bird <tim.bird@am.sony.com>
Cc: linux kernel <linux-kernel@vger.kernel.org>
Subject: Re: kfree(0) - ok?
Date: Tue, 14 Aug 2007 15:55:48 -0700 [thread overview]
Message-ID: <1187132149.2618.2.camel@laptopd505.fenrus.org> (raw)
In-Reply-To: <46C233CB.9000602@am.sony.com>
On Tue, 2007-08-14 at 15:59 -0700, Tim Bird wrote:
> Hi all,
>
> I have a quick question.
>
> I'm trying to resurrect a patch from the Linux-tiny patch suite,
> to do accounting of kmalloc memory allocations. In testing it
> with Linux 2.6.22, I've found a large number of kfrees of
> NULL pointers.
>
> Is this considered OK? Or should I examine the offenders
> to see if something is coded badly?
kfree(NULL) is explicitly ok and it saves code size to not check
anywhere
(the idea is that kfree(kmalloc(...)); is a guaranteed safe nop)
NULL is not 0 though.
next prev parent reply other threads:[~2007-08-14 23:00 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-08-14 22:59 Tim Bird
2007-08-14 22:55 ` Arjan van de Ven [this message]
2007-08-14 23:21 ` Jason Uhlenkott
2007-08-15 7:28 ` Jan Engelhardt
2007-08-15 8:37 ` Rene Herman
2007-08-15 9:20 ` Jan Engelhardt
2007-08-15 9:43 ` Jason Uhlenkott
2007-08-15 9:58 ` Rene Herman
2007-08-15 10:20 ` Jan Engelhardt
2007-08-15 10:27 ` Rene Herman
2007-08-15 13:58 ` Kyle Moffett
2007-08-15 14:06 ` Jan Engelhardt
2007-08-15 14:34 ` Kyle Moffett
2007-08-15 16:01 ` H. Peter Anvin
2007-08-15 8:52 ` Jason Uhlenkott
2007-08-15 9:18 ` Andreas Schwab
2007-08-15 9:32 ` Giacomo A. Catenazzi
2007-08-14 23:42 ` Satyam Sharma
2007-08-15 0:19 ` Christoph Lameter
2007-08-17 18:22 ` Andrew Morton
2007-08-17 18:31 ` Arjan van de Ven
2007-08-17 18:50 ` Satyam Sharma
2007-08-17 18:37 ` Jan Engelhardt
2007-08-17 20:43 ` Christoph Lameter
2007-08-17 21:17 ` Satyam Sharma
2007-08-17 21:32 ` Satyam Sharma
2007-08-17 21:13 ` Satyam Sharma
2007-08-17 21:14 ` Christoph Lameter
2007-08-17 21:42 ` Pekka Enberg
2007-08-17 23:22 ` Christoph Lameter
2007-08-17 23:40 ` Thomas Gleixner
2007-08-18 0:02 ` Satyam Sharma
2007-08-18 1:03 ` Christoph Lameter
2007-08-18 8:10 ` Pekka Enberg
2007-08-18 8:21 ` Jan Engelhardt
2007-08-17 21:46 ` Satyam Sharma
2007-08-14 23:13 ` Satyam Sharma
[not found] <fa.oMJ6o9vN0dnAoFR83/o4hg1EptE@ifi.uio.no>
2007-08-14 23:05 ` Robert Hancock
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