[PATCH 00/12] breakpoint: Rework arch validation v2

From: Frederic Weisbecker
Date: Fri May 18 2018 - 21:50:08 EST



Changes since v1:

- Avoid arch code duplication between check and commit. Use a temporary
struct arch_hw_breakpoint to fill up arch data on the fly
(Mark Rutland)

- Start with a default weak version of hw_breakpoint_arch_parse() that
architectures override one by one (Peter Zijlstra, Andy Lutomirski)

git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
perf/breakpoint-v2

HEAD: a350174ed8f7240b91ae46933bfe2274d3d03806

--- Summary ---

When we modify a hardware breakpoint, the architecture code fills up
the architecture data as the validation of generic attributes progresses.
If something goes wrong in the middle, the architecture data changes
aren't rolled back and we are left with a halfway fiddled breakpoint.

This set fixes the various misdesigns that back this bad behaviour.

Thanks,
Frederic
---

Frederic Weisbecker (12):
perf/breakpoint: Split attribute parse and commit
perf/breakpoint: Pass arch breakpoint struct to arch_check_bp_in_kernelspace()
x86: Implement hw_breakpoint_arch_parse()
powerpc: Implement hw_breakpoint_arch_parse()
arm: Implement hw_breakpoint_arch_parse()
arm64: Implement hw_breakpoint_arch_parse()
sh: Remove "struct arch_hw_breakpoint::name" unused field
sh: Implement hw_breakpoint_arch_parse()
xtensa: Implement hw_breakpoint_arch_parse()
perf/breakpoint: Remove default hw_breakpoint_arch_parse()
perf/breakpoint: Pass new breakpoint type to modify_breakpoint_slot()
perf/breakpoint: Clean up and consolidate modify_user_hw_breakpoint_check()


arch/arm/include/asm/hw_breakpoint.h | 7 +-
arch/arm/kernel/hw_breakpoint.c | 78 +++++++++---------
arch/arm64/include/asm/hw_breakpoint.h | 7 +-
arch/arm64/kernel/hw_breakpoint.c | 86 ++++++++++----------
arch/powerpc/include/asm/hw_breakpoint.h | 7 +-
arch/powerpc/kernel/hw_breakpoint.c | 47 ++++++-----
arch/sh/include/asm/hw_breakpoint.h | 8 +-
arch/sh/kernel/hw_breakpoint.c | 53 ++++++-------
arch/x86/include/asm/hw_breakpoint.h | 7 +-
arch/x86/kernel/hw_breakpoint.c | 131 ++++++++++++++++---------------
arch/xtensa/include/asm/hw_breakpoint.h | 7 +-
arch/xtensa/kernel/hw_breakpoint.c | 40 ++++------
kernel/events/hw_breakpoint.c | 92 +++++++++++++---------
13 files changed, 294 insertions(+), 276 deletions(-)