Re: get_user_pages() still broken in 2.6

Timur Tabi
2004-09-29T14:46:38Z

Dave Hansen wrote:

> You probably want mlock(2) to keep the kernel from messing with the ptes
> at all.

mlock() can only be called via sys_mlock(), which is a user-space call.
Not only that, but only root can call sys_mlock(). This is not
compatible with our needs.

> But, you should probably really be thinking about why you're
> accessing the page tables at all. I count *ONE* instance in drivers/
> where page tables are accessed directly.

I access PTEs to get the physical addresses of a user-space buffer, so
that we can DMA to/from it directly.

--
Timur Tabi
Staff Software Engineer
timur.tabi@ammasso.com