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Subject[PATCH 2/2] Avoid raising segv using an obvious null dereference
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An optimized build such as:
make -C tools/perf CLANG=1 CC=clang EXTRA_CFLAGS="-O3
will turn the dereference operation into a ud2 instruction, raising a SIGILL
rather than a SIGSEGV. Use raise(..) for correctness and clarity.

Similar issues were addressed in Numfor Mbiziwo-Tiapo's patch:
https://lkml.org/lkml/2019/7/8/1234

Signed-off-by: Ian Rogers <irogers@google.com>
---
tools/perf/tests/perf-hooks.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tools/perf/tests/perf-hooks.c b/tools/perf/tests/perf-hooks.c
index dbc27199c65e..dd865e0bea12 100644
--- a/tools/perf/tests/perf-hooks.c
+++ b/tools/perf/tests/perf-hooks.c
@@ -19,12 +19,11 @@ static void sigsegv_handler(int sig __maybe_unused)
static void the_hook(void *_hook_flags)
{
int *hook_flags = _hook_flags;
- int *p = NULL;

*hook_flags = 1234;

/* Generate a segfault, test perf_hooks__recover */
- *p = 0;
+ raise(SIGSEGV);
}

int test__perf_hooks(struct test *test __maybe_unused, int subtest __maybe_unused)
--
2.23.0.351.gc4317032e6-goog
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