Re: unify pagetable accessors patch causes double fault II

[Andi Kleen <andi@firstfloor.org>]

On Tue, Jan 15, 2008 at 02:53:17PM +0100, Ingo Molnar wrote:
> 
> * Jeremy Fitzhardinge <jeremy@goop.org> wrote:
> 
> > Can you try this out?  It applies after "x86: move all asm/pgtable 
> > constants into one place".
> 
> and here's the patch
> 
> Subject: Re: unify pagetable accessors patch causes double fault II
> From: Jeremy Fitzhardinge <jeremy@goop.org>

The patch does not fix the problem here. When I boot plain git-x86
upto commit 67db3027d691ff8049d19be7bc440eca0e5826d7
on my 6GB machine I still get an recursive oops on entering user space.

The only difference to earlier kernels seems to be that the problem
happens a little latter (in stty, not boot), but that might be just
coincidence.

Config http://halobates.de/config32

stty[1151]: segfault at b7f0ce98 ip b7e03b7a sp bfc31f9c error 7
Eeek! page_mapcount(page) went negative! (-1)
  page pfn = bfc12
  page->flags = 80000014
  page->count = 0
  page->mapping = 00000000
  vma->vm_ops = nfs_file_vm_ops+0x0/0x18
  vma->vm_ops->nopage = 0x0
  vma->vm_ops->fault = filemap_fault+0x0/0x34e
  vma->vm_file->f_op->mmap = nfs_file_mmap+0x0/0x61
------------[ cut here ]------------
kernel BUG at /home/lsrc/git-arch-x86/linux-2.6-x86/mm/rmap.c:631!
invalid opcode: 0000 [#1] SMP

-Andi