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Date: Fri, 15 Apr 2016 23:53:28 +0100
From: Matt Fleming <matt@codeblueprint.co.uk>
To: Roger Pau =?iso-8859-1?Q?Monn=E9?= <roger.pau@citrix.com>
Cc: Andy Lutomirski <luto@amacapital.net>, Juergen Gross <jgross@suse.com>,
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Subject: Re: HVMLite / PVHv2 - using x86 EFI boot entry
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(Sorry, just realised I never replied to this)

On Wed, 13 Apr, at 01:59:10PM, Roger Pau Monné wrote:
> 
> Is this header compatible with the ELF header? Con both co-exist in the 
> same binary without issues?
 
Nope, they cannot. We get away with mixing bzImage headers and PE/COFF
headers for the EFI stub because bzImage has no magic string and
contains historical code at the start of the file. The code is never
executed in practice nowadays (it tells the user to use a boot loader
instead of direct execution) so we just stamp a PE/COFF header over it
when CONFIG_EFI_STUB is enabled.