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Date: Mon, 7 Jan 2013 16:53:39 +0100
From: Borislav Petkov <bp@alien8.de>
To: Yinghai Lu <yinghai@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
        "H. Peter Anvin" <hpa@zytor.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
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        Jan Kiszka <jan.kiszka@web.de>,
        Jason Wessel <jason.wessel@windriver.com>,
        linux-kernel@vger.kernel.org,
        Alexander Duyck <alexander.h.duyck@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>
Subject: Re: [PATCH v7u1 05/31] x86, 64bit: copy zero-page early
Message-ID: <20130107155339.GA29449@x1.alien8.de>
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	Yinghai Lu <yinghai@kernel.org>,
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On Thu, Jan 03, 2013 at 04:48:25PM -0800, Yinghai Lu wrote:
> real_mode_data aka zero-page could be above 4g.

I think this could be more informative if it said 'struct boot_params'
instead of real_mode_data because real_mode_data is the argument name
passed to the respective function and grepping for struct boot_params
actually gives you the struct definition with the helpful comments and
offsets in arch/x86/include/uapi/asm/bootparam.h.

> We will have #PF handler to set page table for not accessible ram
> early, but could limit it before x86_64_start_reservations to limit
> the change to native path.
> 
> Also we will need to ramdisk info in zero-page to access microcode
		   s/to/the/				  ^
							the

> blob in ramdisk in x86_64_start_kernel, so copy zero-page early make
								  makes
> it accessing ramdisk info simple.
> 
> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
> Cc: Alexander Duyck <alexander.h.duyck@intel.com>
> Cc: Fenghua Yu <fenghua.yu@intel.com>

-- 
Regards/Gruss,
Boris.