Re: ptrace on linux 2.6.12 causes oops

Yep, just that now its the ptraceing process which is faulting in the 
page,
instead of the (ptraced) process itself.

So Anton, can you move the _tlbie() call up to

&& !test_bit(PG_arch_1, &page->flags)) {
<---------- HERE
if (vma->vm_mm == current->active_mm)
__flush_dcache_icache((void *) address);
else
flush_dcache_icache_page(page);
set_bit(PG_arch_1, &page->flags);

So that it covers both cases instead of just (vma->vm_mm == 
current->active_mm) ?

Its safe to do it because the address space ID is ignored by tlbie 
accordingly
to the manual page:

The ASID value in the entry is ignored for the purpose of
matching an invalidate address, thus multiple entries can be invalidated
if they have the same effective address and different ASID values.

Well, unfortunately, that doesn't work :(. If i'm right, the 
__flush_dcache_icache((void *) address) should avoid that the cache says 
faulting address again.
The flush_dcache_icache_page(page) should flush the cache, where stands, 
page not mapped. but the flush_dcache_icache_page(page) oopses on my system. 
but instead of this call, the call __flush_dcache_icache(page_address(page)) 
works. for me, that also makes more sence. and also, the 
flush_dcache_icache_page(page) calls the flush_dcache_icache_phys, which 
turns off the data virtual address mapping. i found that a bit strange. any 
comments?