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Message-ID: <19f34abd0811250207k3e0991bbgeaa41ccb48f4e4ac@mail.gmail.com>
Date: Tue, 25 Nov 2008 11:07:29 +0100
From: "Vegard Nossum" <vegard.nossum@gmail.com>
To: "Huang Ying" <ying.huang@intel.com>, "Ingo Molnar" <mingo@elte.hu>
Subject: Re: v2.6.28-rc2: x86_32 relocation regression?
Cc: "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
       "H. Peter Anvin" <hpa@zytor.com>
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On Tue, Nov 25, 2008 at 2:30 AM, Huang Ying <ying.huang@intel.com> wrote:
> Hi, Vegard,
>
> On Tue, 2008-11-25 at 05:19 +0800, Vegard Nossum wrote:
> [...]
>> It looks like everything was offset by 0xe00000:
>>
>>     $ addr2line -e vmlinux c119e613
>>     arch/x86/lib/string_32.c:20
>
> Because relocation is supported in recent Linux kernel, it is possible
> that the run-time address is different with compile-time address. In
> most cases, the kernel will be loaded into 0x100000 during boot, so the
> kernel run-time address range from 0xc0100000 on. But it seems that your
> kernel compile-time address range from 0xc0f00000 on. Please check
> CONFIG_PHYSICAL_START in your .config. In most cases, it will be set to
> 0x100000, so that it is same as run-time address in most cases.

Thanks!

It seems to be caused by this commit:

commit 5cb04df8d3f03e37a19f2502591a84156be71772
Author: Ingo Molnar <mingo@elte.hu>
Date:   Sun May 4 19:49:04 2008 +0200

    x86: defconfig updates

-CONFIG_PHYSICAL_START=0x100000
-# CONFIG_RELOCATABLE is not set
-CONFIG_PHYSICAL_ALIGN=0x100000
...
+CONFIG_PHYSICAL_START=0x1000000
+CONFIG_RELOCATABLE=y
+CONFIG_PHYSICAL_ALIGN=0x200000

Were all changes intentional?


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036