please pull powerpc-merge.git

[Paul Mackerras]

Linus Torvalds writes:

> Hey, I just got an oops.
> 
> This was with a plain 2.6.15-rc1 kernel (so before the merge):
> 
> 	Unable to handle kernel paging request for data at address 0xc0000000ff000000

How much RAM do you have?  That address is in the I/O hole (from 2G to
4G).

> 	NIP [C000000000031200] .clear_user_page+0x10/0x60
...
> 	[C0000001561F3B50] [C000000000097B24] .__handle_mm_fault+0xd34/0xf10 (unreliable)
> 	[C0000001561F3C60] [C00000000049729C] .do_page_fault+0x4ec/0x7f0
> 	[C0000001561F3E30] [C000000000004760] .handle_page_fault+0x20/0x54

That looks like just an ordinary page fault that got a bad address
back from alloc_page_vma in alloc_zeroed_user_highpage.  Why, I have
no idea.

> (There are other reports of VM-induced problems on -rc1, this is probably 
> not ppc64-related).

Looks that way to me...

Paul.