[PATCH 00/13] x86/debug: Untangle handle_debug()

From: Peter Zijlstra
Date: Wed Sep 02 2020 - 11:46:49 EST


Hi,

The first two patches probably ought to go in x86/urgent, the rest (!RFC) can
go into x86/core and wait a bit.

handle_debug() is a mess, and now that we have separate user and kernel paths,
try and clean it up a bit.

There's two RFC patches at the end that impact the ptrace_{get,set}_debugreg(6)
ABI, I've no idea what, if anything, is expected of that or if anybody actually
cares about that. If I read the code correctly nothing actually consumes the
value from ptrace_set_debugreg(6).

Kyle, you seem to be pushing all this to the edge with RR, any clues?

Since v2:

- fixed (user) INT1 / icebp detection
- some further cleanups
- two additional RFC patches