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Date: Wed, 1 Aug 2007 14:02:29 +1000
From: Paul Mackerras <paulus@samba.org>
To: Greg KH <gregkh@suse.de>
Cc: Andreas Schwab <schwab@suse.de>, WANG Cong <xiyou.wangcong@gmail.com>,
       Satyam Sharma <satyam@infradead.org>,
       Christian Borntraeger <borntraeger@de.ibm.com>,
       jack@hawkeye.stone.uk.eu.org, linux-kernel@vger.kernel.org,
       trivial@kernel.org
Subject: Re: [Patch 09/16] Remove unnecessary kmalloc casts in the pci
	subsystem.
In-Reply-To: <20070731174755.GA8592@suse.de>
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Greg KH writes:

> On Tue, Jul 31, 2007 at 06:20:29PM +0200, Andreas Schwab wrote:
> > Greg KH <gregkh@suse.de> writes:
> > 
> > > On Tue, Jul 31, 2007 at 10:46:19PM +0800, WANG Cong wrote:
> > >> However, I think using resource_size_t is a bit better than unsigned long,
> > >> so that we don't need to check the defination of it.
> > >> 
> > >> - res->start = (unsigned long)kmalloc(*size, GFP_KERNEL);
> > >> + res->start = (resource_size_t)kmalloc(*size, GFP_KERNEL);
> > >> 
> > >> Is this change OK?
> > >
> > > Yes, that is the proper cast to have here.
> > 
> > It will generate a warning when resoure_size_t is 64bit on a 32bit arch.
> 
> How?  And if so, what should the proper cast be?

You'll get a "cast from pointer to different-sized integer" type of
warning.  The proper cast is unsigned long, just like the code is
without this patch. :)

Paul.