| commit | fb242be88da991bc7b03d74c049062174544c290 | [log] [tgz] |
|---|---|---|
| author | Rob Herring <[email protected]> | Tue Mar 09 17:44:12 2021 -0700 |
| committer | Greg Kroah-Hartman <[email protected]> | Wed Mar 17 17:06:28 2021 +0100 |
| tree | 2d362a18938799f89162a2cd3643957fda2ab641 | |
| parent | ffb9a77d0a7fe47044795748eabcc8c68f65c0bc [diff] |
arm64: perf: Fix 64-bit event counter read truncation
commit 7bb8bc6eb550116c504fb25af8678b9d7ca2abc5 upstream.
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.
Cc: Alexandru Elisei <[email protected]>
Cc: Julien Thierry <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: <[email protected]>
Fixes: 0fdf1bb75953 ("arm64: perf: Avoid PMXEV* indirection")
Signed-off-by: Rob Herring <[email protected]>
Acked-by: Mark Rutland <[email protected]>
Reviewed-by: Alexandru Elisei <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index 3605f77a..11852e0 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);