double fault -> PAGE_KERNEL flagged memory

[Frank Ch. Eigler]

Mathieu Desnoyers wrote:

> [...]  For Tom : can you flag the RelayFS buffer memory PAGE_KERNEL
> instead of GFP_KERNEL ? Otherwise, it leads to page faults when
> accessing those pages when accessed for the first time (seen with
> LTTng).

FWIW, relayfs is not used by default.

> [...]  Make sure that the SystemTAP code is _always_ in contiguous
> memory non swappable to disk :

Is my impression correct that no ordinary kernel-allocated memory such
as .ko .text/.data is swappable?  Remember, this is what systemtap
creates, plus a few batches of dynamically allocated (k/vmalloc)
memory during module initialization.

- FChE