From: Namhyung Kim <namhyung@kernel.org>

Date: Wed, 26 Apr 2023 20:05:27 -0700

Subject: [PATCH] perf/x86: Fix missing sample size update on AMD BRS

References: bsc#1012628

Patch-mainline: 6.3.3

Git-commit: 90befef5a9e820ccccc33181ec14c015980300cc

commit 90befef5a9e820ccccc33181ec14c015980300cc upstream.

It missed to convert a PERF_SAMPLE_BRANCH_STACK user to call the new

perf_sample_save_brstack() helper in order to update the dyn_size.

This affects AMD Zen3 machines with the branch-brs event.

Fixes: eb55b455ef9c ("perf/core: Add perf_sample_save_brstack() helper")

Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>

Cc: stable@vger.kernel.org

Link: https://lkml.kernel.org/r/20230427030527.580841-1-namhyung@kernel.org

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 arch/x86/events/core.c | 6 ++----

 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c

index d096b04b..9d248703 100644

--- a/arch/x86/events/core.c

+++ b/arch/x86/events/core.c

@@ -1703,10 +1703,8 @@ int x86_pmu_handle_irq(struct pt_regs *regs)

 		perf_sample_data_init(&data, 0, event->hw.last_period);

-		if (has_branch_stack(event)) {

-			data.br_stack = &cpuc->lbr_stack;

-			data.sample_flags |= PERF_SAMPLE_BRANCH_STACK;

-		}

+		if (has_branch_stack(event))

+			perf_sample_save_brstack(&data, event, &cpuc->lbr_stack);

 		if (perf_event_overflow(event, &data, regs))

 			x86_pmu_stop(event, 0);

-- 

2.35.3