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Date: Tue, 15 May 2012 14:20:06 +0100
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Jan Beulich <JBeulich@suse.com>
Cc: mingo@elte.hu, tglx@linutronix.de, matt.fleming@linux.intel.com,
        linux-kernel@vger.kernel.org, hpa@zytor.com
Subject: Re: [PATCH] x86-64: use EFI to deal with platform wall clock
Message-ID: <20120515132006.GA26196@srcf.ucam.org>
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On Tue, May 15, 2012 at 02:19:07PM +0100, Jan Beulich wrote:

> I would have expected that things work that way, but they
> don't. In particular is the function in efi_64.c that's being
> modified here called from efi_call_phys_{pro,epi}log(), and at
> that point we can't expect virtual addresses to be uniformly
> set yet. So it's a physical call that requires the fixup done
> here, as efi_set_executable() simply expects ->virt_addr to
> be valid. I suspect that no physical calls other than
> phys_efi_set_virtual_address_map() were being done so far
> at all on 64-bit, hiding the problem.

In that case we need to split the mapping code into two chunks and 
configure the memory map earlier. You can't depend on __va() doing 
anything useful on runtime addresses.

-- 
Matthew Garrett | mjg59@srcf.ucam.org
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