6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chun-Tse Shao <ctshao@xxxxxxxxxx> [ Upstream commit 02a55f2743012a8089f09f6867220c3d57f16564 ] Same as https://lore.kernel.org/all/20240514180050.182454-1-namhyung@xxxxxxxxxx/, we should skip `for_each_sibling_event()` for group leader since it doesn't have the ctx yet. Fixes: f3c0eba28704 ("perf: Add a few assertions") Reported-by: Greg Thelen <gthelen@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Tuan Phan <tuanphan@xxxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Chun-Tse Shao <ctshao@xxxxxxxxxx> Acked-by: Will Deacon <will@xxxxxxxxxx> Link: https://lore.kernel.org/r/20241108050806.3730811-1-ctshao@xxxxxxxxxx Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/perf/arm_smmuv3_pmu.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c index d5fa92ba83739..dabdb9f7bb82c 100644 --- a/drivers/perf/arm_smmuv3_pmu.c +++ b/drivers/perf/arm_smmuv3_pmu.c @@ -431,6 +431,17 @@ static int smmu_pmu_event_init(struct perf_event *event) return -EINVAL; } + /* + * Ensure all events are on the same cpu so all events are in the + * same cpu context, to avoid races on pmu_enable etc. + */ + event->cpu = smmu_pmu->on_cpu; + + hwc->idx = -1; + + if (event->group_leader == event) + return 0; + for_each_sibling_event(sibling, event->group_leader) { if (is_software_event(sibling)) continue; @@ -442,14 +453,6 @@ static int smmu_pmu_event_init(struct perf_event *event) return -EINVAL; } - hwc->idx = -1; - - /* - * Ensure all events are on the same cpu so all events are in the - * same cpu context, to avoid races on pmu_enable etc. - */ - event->cpu = smmu_pmu->on_cpu; - return 0; } -- 2.43.0
