On Saturday 11 August 2007 00:00:12 akpm@linux-foundation.org wrote:

From: Christoph Hellwig <hch@lst.de>

x86(-64) are the last architectures still using the page fault notifier
cruft for the kprobes page fault hook.  This patch converts them to the
proper direct calls, and removes the now unused pagefault notifier bits
aswell as the cruft in kprobes.c that was related to this mess.

I know Andi didn't really like this, but all other architecture maintainers
agreed the direct calls are much better and besides the obvious cruft
removal a common way of dealing with kprobes across architectures is
important aswell.

This means the debuggers just have to readd it. Not merged.

If you worry about cycles notifiers could be probably optimized a bit
for the nothing registered case.

-Andi