Re: [PATCH 1/5] freepgt: free_pgtables use vma list

Hugh Dickins
2005-03-22T05:53:54Z

On Mon, 21 Mar 2005, David S. Miller wrote:
>
> flush_tlb_pgtables() on sparc64 has a BUG() check which
> is basically:
>
> BUG((long)start > (long)end);
>
> This catches two cases of bogus arguments:
>
> 1) start --> end straddles sparc64 address space hole

That's an interesting remark. I hadn't noticed the signed long type.
I believe the vma gathering in free_pgtables will have no problem with
that, but what about the old code? What happens if an app does a huge
munmap straddling the address space hole? Or is all the user address
space below the hole?

Hugh