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Date: Tue, 24 Jun 2008 19:55:44 +0200 (CEST)
From: Julia Lawall <julia@diku.dk>
To: "Luck, Tony" <tony.luck@intel.com>
Cc: "akinobu.mita@gmail.com" <akinobu.mita@gmail.com>,
       "linux-ia64@vger.kernel.org" <linux-ia64@vger.kernel.org>,
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Subject: RE: [PATCH 3/14] arch/ia64: Eliminate NULL test and memset after
 alloc_bootmem
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On Tue, 24 Jun 2008, Luck, Tony wrote:

> > As noted by Akinobu Mita in patch b1fceac2b9e04d278316b2faddf276015fc06e3b,
> > alloc_bootmem and related functions never return NULL and always return a
> > zeroed region of memory.  Thus a NULL test or memset after calls to these
> > functions is unnecessary.
> 
> There is no commit b1fceac2b9e04d278316b2faddf276015fc06e3b in Linus' tree.

I am not sure to know how to tell precisely where you are looking, but you 
can find it here:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=b1fceac2b9e04d278316b2faddf276015fc06e3b


> In addition the current alloc_bootmem() is a macro that uses __alloc_bootmem
> which most defintely can return NULL.

The "return NULL;" at the bottom of __alloc_bootmem is preceded by 
panic("Out of memory");, which I assume cannot return?

> Is this against -mm or linux-next?

I pull files from the following git repository:

git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git

julia