From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@linux-foundation.org>
Date: Wed, 13 Feb 2013 00:22:22 +0000
Subject: Re: [PATCH V3] ia64/mm: fix a bad_page bug when crash kernel booting
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To: Tony Luck <tony.luck@gmail.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>, Matt Fleming <matt.fleming@intel.com>, fenghua.yu@intel.com, Liujiang <jiang.liu@huawei.com>, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, linux-mm@kvack.org, Hanjun Guo <guohanjun@huawei.com>, WuJianguo <wujianguo@huawei.com>

On Tue, 12 Feb 2013 16:11:33 -0800
Tony Luck <tony.luck@gmail.com> wrote:

> Building linux-next today (tag next-20130212) I get the following errors when
> building arch/ia64/configs/{tiger_defconfig, zx1_defconfig, bigsur_defconfig,
> sim_defconfig}
> 
> arch/ia64/mm/init.c: In function 'free_initrd_mem':
> arch/ia64/mm/init.c:215: error: 'max_addr' undeclared (first use in
> this function)
> arch/ia64/mm/init.c:215: error: (Each undeclared identifier is
> reported only once
> arch/ia64/mm/init.c:215: error: for each function it appears in.)
> arch/ia64/mm/init.c:216: error: implicit declaration of function
> 'GRANULEROUNDDOWN'
> 

`max_addr' is an awesomely bad name for a global identifier, btw.

And this:

-static u64 mem_limit = ~0UL, max_addr = ~0UL, min_addr = 0UL;
+u64 mem_limit = ~0UL, max_addr = ~0UL, min_addr = 0UL;

needlessly exported `mem_limit' and `min_addr' as well.  These too are
very poor global identifiers.

Also, Matt suggested an alternative implementation which afaik hasn't
been responded to.


I think I'll just drop the patch.