This is a note to let you know that I've just added the patch titled
perf/x86: Avoid exposing wrong/stale data in intel_pmu_lbr_read_32()
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
perf-x86-avoid-exposing-wrong-stale-data-in-intel_pmu_lbr_read_32.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From f2200ac311302fcdca6556fd0c5127eab6c65a3e Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Date: Tue, 11 Apr 2017 10:10:28 +0200
Subject: perf/x86: Avoid exposing wrong/stale data in intel_pmu_lbr_read_32()
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
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@xxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Fixes: 135c5612c460 ("perf/x86/intel: Support Haswell/v4 LBR format")
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/perf_event_intel_lbr.c | 3 +++
1 file changed, 3 insertions(+)
--- 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
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;
Patches currently in stable-queue which might be from peterz@xxxxxxxxxxxxx are
queue-4.4/x86-vdso-ensure-vdso32_enabled-gets-set-to-valid-values-only.patch
queue-4.4/x86-vdso-plug-race-between-mapping-and-elf-header-setup.patch
queue-4.4/cgroup-kthread-close-race-window-where-new-kthreads-can-be-migrated-to-non-root-cgroups.patch
queue-4.4/perf-x86-avoid-exposing-wrong-stale-data-in-intel_pmu_lbr_read_32.patch