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Re: [Xen-devel] [PATCH] Elf loader fixes

To: Jan Beulich <JBeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH] Elf loader fixes
From: Gerd Hoffmann <kraxel@xxxxxxx>
Date: Wed, 22 Feb 2006 17:10:42 +0100
Cc: Xen devel list <xen-devel@xxxxxxxxxxxxxxxxxxx>
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>> The elf kernel loader certainly doesn't look like it cares much
>> about virtual address (other than VIRT_BASE) ...
> Correct. And the same applies to boot loaders.

Well, the difference between xen and other boot loaders is that xen
boots the kernel with paging already enabled ...

Right now it's completely broken: the loader works only with virtual
addresses in the paddr header field.  It can't stay that way, especially
if we'll want to have kexec working with xenlinux kernels some day ;)

As I see things there are basically two ways to fixup this: Either
create a simple linear mapping using paddr + VIRT_BASE, which would be
pretty close to the current behaviour (and other boot loaders). Or do a
complete virtual memory setup, which probably can't be done without
major changes in the domain builder ...



Gerd 'just married' Hoffmann <kraxel@xxxxxxx>
I'm the hacker formerly known as Gerd Knorr.

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