Re: Fwd: Hurd shutdown problems

[Samuel Thibault]

Richard Braun, on Fri 12 Aug 2016 19:50:51 +0200, wrote:
> On Fri, Aug 12, 2016 at 07:08:07PM +0200, Samuel Thibault wrote:
> > More precisely though, adding debugging to vm_page_load:
> > 
> > vm_page_load 10000-1000000 10000-1000000
> > vm_page_load 1000000-7a000000 114f000-79c41000
> > vm_page_load 7a000000-7ffe0000 7a000000-7ffe0000
> > 
> > I.e. it properly skips the kernel (1000000-114f000), but nothing else.
> > 
> > What is supposed to exclude everything else? (modules, VGA BIOS, etc.)
> 
> Look at the vm_page_load calls and you'll see there is a range of
> available pages inside each loaded region.

That's what I'm talking about, and that's the second part of the printfs
above, and they are wrong: 10000-1000000 is definitely wrong on a PC,
and it includes the debugging symbols.

> 3/ When enabling the virtual memory system, biosmem_setup is called.
> It loads each segment into the vm_page module, but is careful to clip
> the biosmem heap from them.

But nothing else.

> When loading a segment, the biosmem heap
> part is passed as [avail_start, avail_end] to vm_page_load.

> To properly answer your question, step 1/ is what looks at the boot
> data (biosmem_find_boot_data) so that the resulting heap boundaries
> completely exclude any.

Yes, but only the heap. The load of segments not containing the heap is
full:

vm_page_load 10000-1000000 10000-1000000
vm_page_load 7a000000-7ffe0000 7a000000-7ffe0000

Samuel