Re: new x86 setup code hangs on Dell Inspiron 5150

[Will Simoneau <simoneau@ele.uri.edu>]

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On 23:41 Thu 30 Aug     , H. Peter Anvin wrote:
> H. Peter Anvin wrote:
>> Will Simoneau wrote:
>>> While trying to put together a new kernel for my laptop (Dell I5150, as
>>> in subject) I found that recent kernels just don't boot. Right after
>>> grub loads the kernel, before the "Uncompressing Linux" message is
>>> shown, it hangs. The BIOS appears to still be alive (ctrl-alt-del works,
>>> keyboard lock LEDs respond). It seems to be caused by the new x86 setup
>>> code.
>>>
>>> My kernel is Linus' git as of a1c582d0720f2eff61043e90711767decf37b917.
>>> I bisected and confirmed that 4fd06960f120e02e9abc802a09f9511c400042a5
>>> triggers a non-functioning boot.
>>>
>>> This system has Dell BIOS rev A38 and a P4 3.2 w/HT.
>>>
>>> What should I do next to debug this problem?
>> Can you put in some printf's in the code and see how far it gets?
>
> Specifically, the places to add printf's are to main() in main.c and 
> go_to_protected_mode() in pm.c.
>
> 	-hpa

It dies in vesa_probe() right after calling int10 with ax=4f01 and
checking the return status, which was 0x004f (success). This happens on
the third iteration of the loop; the first two modes it finds are
framebuffer modes. This would be just after line 72 in video-vesa.c .

I have CONFIG_VIDEO_VESA=y and CONFIG_FB=y, but am not passing the
kernel options that would use vesafb as the console.

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