Re: [PATCH 0/13] maps: pagemap, kpagemap, and related cleanups

Nick Piggin
2007-04-13T12:46:28Z

Ananth N Mavinakayanahalli wrote:
> On Fri, Apr 13, 2007 at 12:50:20PM +1000, Nick Piggin wrote:

>>It definitely seems like you can use some kernel functions, but the
>>ones I saw may just be systemtap facilities. But what is so surprising
>>about being able to call a kernel function when running in kernel
>>context? Perhaps there is some fundamental limitation of kprobes that
>>I don't understand.
>
>
> The main requirement for kprobes handlers is that they can't sleep. You
> could definitely call a kernel function from kprobe handlers as long as
> the function doesn't sleep.

That would be enough to access basically all the VM data structures.

--
SUSE Labs, Novell Inc.