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Date: Thu, 21 Jul 2016 18:18:07 +0200
From: Ingo Molnar <mingo@kernel.org>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Matt Fleming <mfleming@suse.de>, Thomas Gleixner <tglx@linutronix.de>,
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        "H. Peter Anvin" <hpa@zytor.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH] x86/boot: Reorganize and clean up the BIOS area
 reservation code
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* Andy Lutomirski <luto@amacapital.net> wrote:

> It would be very easy to implement this if we could handle overlapping memblocks 
> precisely or set a lower limit on the memblock allocator. Then we could block 
> off everything below 1MB or 2MB very early and then unblock it or temporarily 
> change the lower limit and ask for a single page for the trampoline after that.

So my suggestion was/is to _permanently_ allocate the SMP trampoline page, and 
leave it also reserved.

'Reserving' a memory area is really just a kernel internal matter. We can still 
use it. No need to unreserve/allocate/re-reserve ... unless I'm missing something.

Thanks,

	Ingo