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| author | Kan Liang <kan.liang@linux.intel.com> | 2018-04-25 14:57:17 -0400 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2018-04-25 21:41:22 +0200 |
| commit | 4e949e9b9d1e3edcdab3b54656c5851bd9e49c67 (patch) | |
| tree | 13ba7875d137a83f1c330c8a7476d3267da50050 /arch | |
| parent | 6d08b06e67cd117f6992c46611dfb4ce267cd71e (diff) | |
| download | linux-0-day-4e949e9b9d1e3edcdab3b54656c5851bd9e49c67.tar.gz linux-0-day-4e949e9b9d1e3edcdab3b54656c5851bd9e49c67.tar.xz | |
perf/x86/intel: Don't enable freeze-on-smi for PerfMon V1
The SMM freeze feature was introduced since PerfMon V2. But the current
code unconditionally enables the feature for all platforms. It can
generate #GP exception, if the related FREEZE_WHILE_SMM bit is set for
the machine with PerfMon V1.
To disable the feature for PerfMon V1, perf needs to
- Remove the freeze_on_smi sysfs entry by moving intel_pmu_attrs to
intel_pmu, which is only applied to PerfMon V2 and later.
- Check the PerfMon version before flipping the SMM bit when starting CPU
Fixes: 6089327f5424 ("perf/x86: Add sysfs entry to freeze counters on SMI")
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: ak@linux.intel.com
Cc: eranian@google.com
Cc: acme@redhat.com
Link: https://lkml.kernel.org/r/1524682637-63219-1-git-send-email-kan.liang@linux.intel.com
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/events/intel/core.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 607bf565a90c9..707b2a96e516b 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3339,7 +3339,8 @@ static void intel_pmu_cpu_starting(int cpu) cpuc->lbr_sel = NULL; - flip_smm_bit(&x86_pmu.attr_freeze_on_smi); + if (x86_pmu.version > 1) + flip_smm_bit(&x86_pmu.attr_freeze_on_smi); if (!cpuc->shared_regs) return; @@ -3502,6 +3503,8 @@ static __initconst const struct x86_pmu core_pmu = { .cpu_dying = intel_pmu_cpu_dying, }; +static struct attribute *intel_pmu_attrs[]; + static __initconst const struct x86_pmu intel_pmu = { .name = "Intel", .handle_irq = intel_pmu_handle_irq, @@ -3533,6 +3536,8 @@ static __initconst const struct x86_pmu intel_pmu = { .format_attrs = intel_arch3_formats_attr, .events_sysfs_show = intel_event_sysfs_show, + .attrs = intel_pmu_attrs, + .cpu_prepare = intel_pmu_cpu_prepare, .cpu_starting = intel_pmu_cpu_starting, .cpu_dying = intel_pmu_cpu_dying, @@ -3911,8 +3916,6 @@ __init int intel_pmu_init(void) x86_pmu.max_pebs_events = min_t(unsigned, MAX_PEBS_EVENTS, x86_pmu.num_counters); - - x86_pmu.attrs = intel_pmu_attrs; /* * Quirk: v2 perfmon does not report fixed-purpose events, so * assume at least 3 events, when not running in a hypervisor: |