perf/hw_breakpoint: Fix arch_hw_breakpoint use-before-initialization
authorMark-PK Tsai <mark-pk.tsai@mediatek.com>
Fri, 6 Sep 2019 06:01:16 +0000 (14:01 +0800)
committerIngo Molnar <mingo@kernel.org>
Fri, 6 Sep 2019 06:24:01 +0000 (08:24 +0200)
commit310aa0a25b338b3100c94880c9a69bec8ce8c3ae
tree8914f769fdcf64d0c2f343ad79c40ebeac29fbae
parent0f4cd769c410e2285a4e9873a684d90423f03090
perf/hw_breakpoint: Fix arch_hw_breakpoint use-before-initialization

If we disable the compiler's auto-initialization feature, if
-fplugin-arg-structleak_plugin-byref or -ftrivial-auto-var-init=pattern
are disabled, arch_hw_breakpoint may be used before initialization after:

  9a4903dde2c86 ("perf/hw_breakpoint: Split attribute parse and commit")

On our ARM platform, the struct step_ctrl in arch_hw_breakpoint, which
used to be zero-initialized by kzalloc(), may be used in
arch_install_hw_breakpoint() without initialization.

Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alix Wu <alix.wu@mediatek.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: YJ Chiang <yj.chiang@mediatek.com>
Link: https://lkml.kernel.org/r/20190906060115.9460-1-mark-pk.tsai@mediatek.com
[ Minor edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel/events/hw_breakpoint.c