Message-ID: <1415874993.14686.434.camel@mfleming-mobl1.ger.corp.intel.com>
Subject: Re: BUG() at boot in __phys_addr with DEBUG_VIRTUAL
From: Matt Fleming <matt.fleming@intel.com>
To: Borislav Petkov <bp@suse.de>
CC: Dave Hansen <dave.hansen@intel.com>,
        the arch/x86 maintainers <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
Date: Thu, 13 Nov 2014 10:36:33 +0000
In-Reply-To: <20141112172513.GC17793@pd.tnic>
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	 <54637576.7030004@intel.com> <20141112151106.GB17793@pd.tnic>
	 <54637AD5.6060300@intel.com> <20141112172513.GC17793@pd.tnic>
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On Wed, 2014-11-12 at 18:25 +0100, Borislav Petkov wrote:
> 
> But before we do that: Matt, why do we need the kernel text mapped 1:1
> in the EFI page table at all?
> 
> You've added this with
> 
> 4f9dbcfc4029 ("x86/efi: Add mixed runtime services support")

So that when we switch into 32-bit mode we can still access the kernel
text via the 1:1 mapping in protected mode.

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