Re: 2.6.4-mm1 - 4g patch breaks when X86_4G not selected

Ingo Molnar
2004-03-15T09:18:47Z

* Neil Brown <neilb@cse.unsw.edu.au> wrote:

> And it turns out it was spot on. Applying 4g-2.6.0-test2-mm2-A5.patch
> (on top of preceding -mm1 patches) causes my server not to boot.

hm. Since your .config boots on akpm's box, this is some BIOS dependency
creating an early-boot problem i fear. Debugging such bugs is hard. One
way would be via the PC speaker:

movb $0x3,%al; outb %al,$0x61

this will cause a continuous beep on a typical PC - it works in 16-bit
code too, doesnt have any memory-model assumptions, etc.

the first place to put this would be startup_32 - do we get to this
point at all? (check CONFIG_4G first, to make sure the beep triggers.)
If it beeps, then move it down until you find the place that crashes.

Ingo