perf/x86: Avoid exposing wrong/stale data in intel_pmu_lbr_read_32()

commit f2200ac311302fcdca6556fd0c5127eab6c65a3e upstream.

When the perf_branch_entry::{in_tx,abort,cycles} fields were added,
intel_pmu_lbr_read_32() wasn't updated to initialize them.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Fixes: 135c5612c460 ("perf/x86/intel: Support Haswell/v4 LBR format")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
index 659f01e165d57520f33b09ba68818f72cd206a4d..8900400230c623e57e2447b7288796d541c74831 100644 (file)
--- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
@@ -410,6 +410,9 @@ static void intel_pmu_lbr_read_32(struct cpu_hw_events *cpuc)
                cpuc->lbr_entries[i].to         = msr_lastbranch.to;
                cpuc->lbr_entries[i].mispred    = 0;
                cpuc->lbr_entries[i].predicted  = 0;
+               cpuc->lbr_entries[i].in_tx      = 0;
+               cpuc->lbr_entries[i].abort      = 0;
+               cpuc->lbr_entries[i].cycles     = 0;
                cpuc->lbr_entries[i].reserved   = 0;
        }
        cpuc->lbr_stack.nr = i;