Commit 0fdf1bb75953 ("arm64: perf: Avoid PMXEV* indirection") changed armv8pmu_read_evcntr() to return a u32 instead of u64. The result is silent truncation of the event counter when using 64-bit counters. Given the offending commit appears to have passed thru several folks, it seems likely this was a bad rebase after v8.5 PMU 64-bit counters landed.
Fixes: 0fdf1bb75953 ("arm64: perf: Avoid PMXEV* indirection") Cc: Alexandru Elisei <alexandru.eli...@arm.com> Cc: Julien Thierry <julien.thierry.k...@gmail.com> Cc: Mark Rutland <mark.rutl...@arm.com> Cc: Will Deacon <w...@kernel.org> Cc: Catalin Marinas <catalin.mari...@arm.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Ingo Molnar <mi...@redhat.com> Cc: Arnaldo Carvalho de Melo <a...@kernel.org> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com> Cc: Jiri Olsa <jo...@redhat.com> Cc: Namhyung Kim <namhy...@kernel.org> Signed-off-by: Rob Herring <r...@kernel.org> --- arch/arm64/kernel/perf_event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index 7d2318f80955..4658fcf88c2b 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c @@ -460,7 +460,7 @@ static inline int armv8pmu_counter_has_overflowed(u32 pmnc, int idx) return pmnc & BIT(ARMV8_IDX_TO_COUNTER(idx)); } -static inline u32 armv8pmu_read_evcntr(int idx) +static inline u64 armv8pmu_read_evcntr(int idx) { u32 counter = ARMV8_IDX_TO_COUNTER(idx); -- 2.27.0