From 201aa8c3bc08ce144ca0ccd563daeb56bfc87ba0 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 15 Mar 2013 13:56:44 -0700 Subject: [PATCH] 3.8-stable patches added patches: perf-x86-fix-kernel-crash-with-pebs-bts-after-suspend-resume.patch --- ...h-with-pebs-bts-after-suspend-resume.patch | 80 +++++++++++++++++++ queue-3.8/series | 1 + 2 files changed, 81 insertions(+) create mode 100644 queue-3.8/perf-x86-fix-kernel-crash-with-pebs-bts-after-suspend-resume.patch diff --git a/queue-3.8/perf-x86-fix-kernel-crash-with-pebs-bts-after-suspend-resume.patch b/queue-3.8/perf-x86-fix-kernel-crash-with-pebs-bts-after-suspend-resume.patch new file mode 100644 index 00000000000..f36a15369a5 --- /dev/null +++ b/queue-3.8/perf-x86-fix-kernel-crash-with-pebs-bts-after-suspend-resume.patch @@ -0,0 +1,80 @@ +From 1d9d8639c063caf6efc2447f5f26aa637f844ff6 Mon Sep 17 00:00:00 2001 +From: Stephane Eranian +Date: Fri, 15 Mar 2013 14:26:07 +0100 +Subject: perf,x86: fix kernel crash with PEBS/BTS after suspend/resume + +From: Stephane Eranian + +commit 1d9d8639c063caf6efc2447f5f26aa637f844ff6 upstream. + +This patch fixes a kernel crash when using precise sampling (PEBS) +after a suspend/resume. Turns out the CPU notifier code is not invoked +on CPU0 (BP). Therefore, the DS_AREA (used by PEBS) is not restored properly +by the kernel and keeps it power-on/resume value of 0 causing any PEBS +measurement to crash when running on CPU0. + +The workaround is to add a hook in the actual resume code to restore +the DS Area MSR value. It is invoked for all CPUS. So for all but CPU0, +the DS_AREA will be restored twice but this is harmless. + +Reported-by: Linus Torvalds +Signed-off-by: Stephane Eranian +Signed-off-by: Linus Torvalds +Signed-off-by: Greg Kroah-Hartman + +--- + arch/x86/kernel/cpu/perf_event_intel_ds.c | 8 ++++++++ + arch/x86/power/cpu.c | 2 ++ + include/linux/perf_event.h | 2 ++ + 3 files changed, 12 insertions(+) + +--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c ++++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c +@@ -729,3 +729,11 @@ void intel_ds_init(void) + } + } + } ++ ++void perf_restore_debug_store(void) ++{ ++ if (!x86_pmu.bts && !x86_pmu.pebs) ++ return; ++ ++ init_debug_store_on_cpu(smp_processor_id()); ++} +--- a/arch/x86/power/cpu.c ++++ b/arch/x86/power/cpu.c +@@ -11,6 +11,7 @@ + #include + #include + #include ++#include + + #include + #include +@@ -228,6 +229,7 @@ static void __restore_processor_state(st + do_fpu_end(); + x86_platform.restore_sched_clock_state(); + mtrr_bp_restore(); ++ perf_restore_debug_store(); + } + + /* Needed by apm.c */ +--- a/include/linux/perf_event.h ++++ b/include/linux/perf_event.h +@@ -753,6 +753,7 @@ extern void perf_event_enable(struct per + extern void perf_event_disable(struct perf_event *event); + extern int __perf_event_disable(void *info); + extern void perf_event_task_tick(void); ++extern void perf_restore_debug_store(void); + #else + static inline void + perf_event_task_sched_in(struct task_struct *prev, +@@ -792,6 +793,7 @@ static inline void perf_event_enable(str + static inline void perf_event_disable(struct perf_event *event) { } + static inline int __perf_event_disable(void *info) { return -1; } + static inline void perf_event_task_tick(void) { } ++static inline void perf_restore_debug_store(void) { } + #endif + + #define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x)) diff --git a/queue-3.8/series b/queue-3.8/series index c57910c8c6f..255c88204f5 100644 --- a/queue-3.8/series +++ b/queue-3.8/series @@ -26,3 +26,4 @@ tty-disable-debugging-warning.patch tty-do-not-reset-master-s-packet-mode.patch fix-4-port-and-add-support-for-8-port-unknown-pci-serial-port-cards.patch arm-kirkwood-fix-to-retain-gbe-mac-addresses-for-dt-kernels.patch +perf-x86-fix-kernel-crash-with-pebs-bts-after-suspend-resume.patch -- 2.47.3