Mikael Pettersson wrote:
> My '94 vintage 486 has problems booting 2.5.55 and 2.5.56.
> When it fails, the boot gets to loading the kernel and
> printing "Ok, booting the kernel.". Then there is a short
> pause (line a tenth of a second) and the machine reboots.
> 
> After doing a binary search with "for(;;);" statements
> (printk doesn't work this early) I found that the reboot
> occurs in arch/i386/mm/init.c:kernel_physical_mapping_init():
> (start_kernel() -> setup_arch() -> paging_init() ->
> pagetable_init() -> kernel_physical_mapping_init())
> 

The problem is that one_page_table_init() pulls the rug out from under 
the kernel by installing a new page table before setting it up.  A 486 
has a small TLB so any miss will cause a triple fault and reset.  Try 
this patch and see if it fixes it.

--
				Brian Gerst