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Date: Mon, 26 Feb 2018 11:15:34 +0300
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@suse.de>,
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        kirill.shutemov@linux.intel.com, peterz@infradead.org,
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Subject: Re: [tip:x86/boot] x86/boot/compressed/64: Prepare trampoline memory
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On Mon, Feb 26, 2018 at 11:02:56AM +0300, Kirill A. Shutemov wrote:
...
> > Also, could do a puts() hexdump of the affected memory area _before_ we overwrite 
> > it? Is it empty? Could we add some debug warning that checks that it's all zeroes?
> 
> The problem is that we don't really have a way get a message out of there.
> 
> http://lkml.kernel.org/r/793b9c55-e85b-97b5-c857-dd8edcda4081@zytor.com
> 

I'm sorry for stepping in (since I didn't follow the series in details)
but can't we use vga memory here and print this early data tere?