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Date: Wed, 05 Dec 2012 16:36:29 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Yinghai Lu <yinghai@kernel.org>
CC: Bjorn Helgaas <bhelgaas@google.com>, Matthew Garrett <mjg59@srcf.ucam.org>,
        linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-efi@vger.kernel.org, mfleming@intel.com, dwmw2@infradead.org,
        "Eric W. Biederman" <ebiederm@xmission.com>
Subject: Re: Use PCI ROMs from EFI boot services
References: <1345739803-21017-1-git-send-email-mjg@redhat.com> <CAErSpo6dn_0b8Ngx9VT=ARs_UXQftEx=2Kczeqemtmo0XyKzuQ@mail.gmail.com> <20121203200241.GG5906@thinkpad-t410> <CAE9FiQVdpmmExrPrLf7HYVuo0cTY9Xjn6bWzObbuSSeQ-e1PbA@mail.gmail.com>
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On 12/05/2012 04:15 PM, Yinghai Lu wrote:
> 
> -#ifndef CONFIG_DEBUG_BOOT_PARAMS
> -struct boot_params __initdata boot_params;
> -#else
>  struct boot_params boot_params;
> -#endif

> 
> No, that is not a right fix
> 
> We should only cache pointer to setup_data.
> 
> at the same time we should export setup_data into /sys, so kexec could
> append this pointer to command of
> second kernel, just like kexec append acpi_rsdp.
> That should address DavidW's concern.
> 

I don't see why that isn't the right fix.  We copy the data into
boot_params early in the boot; that *is* the official copy as far as the
kernel is concerned.

So this patch very much seems like The Right Thing.

	-hpa