Re: [PATCH] Fix e820 end address with EFI

From: Yinghai Lu
Date: Sun Mar 01 2009 - 21:17:21 EST


Huang Ying wrote:
> On Mon, 2009-03-02 at 09:39 +0800, Brian Maly wrote:
>> Huang Ying wrote:
>>> Hi, Brian,
>>>
>>> On Mon, 2009-03-02 at 04:13 +0800, Brian Maly wrote:
>>>
>>>> I was able verify the kernel that does not boot on the MacBook (vanilla
>>>> 2.6.29-rc4) does call efi_ioremap() which bails out early returning
>>>> NULL. So no remapping happens in this case. I have no idea if
>>>> efi_ioremap ever does succeed in mapping any ranges though being I have
>>>> no video or console this early in the boot and have to rely on triple
>>>> faulting as a means of debugging.
>>>>
>>> Please attach your dmesg of successful boot, so we can take a look at
>>> the EFI memory map.
>>>
>>> Best Regards,
>>> Huang Ying
>>>
>> This dmesg is from a 2.6.25 kernel which works fine. I can gather
>> other debugging info from the booting kernels if needed. But its a
>> challenge to debug the bad kernel being efifb is initialized very late
>> (so you never even get to the video initialization and cant see any
>> logged messages) and since its a MacBook I dont have a real serial
>> port for serial console. The efi map is for MacBook has a different
>> layout from other EFI systems I have to test on. 2.6.29 kernel works
>> on every EFI system I have except MacBook.
>
> It seems that you have an EFI system which has too big runtime area.
>
> EFI: mem44: type=0, attr=0x8000000000000000, range=[0x000000007ff00000-0x0000000080000000) (1MB)
>
> efi_ioremap() can map only memory range < 400k now.
>
> It seems that efi_ioremap is the bottle net now. Can we just use
> init_memory_mapping() instead of efi_ioremap() for EFI runtime area?
>
> Yinghai, how about your opinion?

you could call init_memory_maping() in that efi_ioremap position?

problems is how about 32bit?

YH
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