From: Kan Liang kan.liang@linux.intel.com
The EAX of the CPUID Leaf 023H enumerates the mask of valid sub-leaves. To tell the availability of the sub-leaf 1 (enumerate the counter mask), perf should check the bit 1 (0x2) of EAS, rather than bit 0 (0x1).
The error is not user-visible on bare metal. Because the sub-leaf 0 and the sub-leaf 1 are always available. However, it may bring issues in a virtualization environment when a VMM only enumerates the sub-leaf 0.
Fixes: eb467aaac21e ("perf/x86/intel: Support Architectural PerfMon Extension leaf") Signed-off-by: Kan Liang kan.liang@linux.intel.com Cc: stable@vger.kernel.org --- arch/x86/events/intel/core.c | 4 ++-- arch/x86/include/asm/perf_event.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 7ca40002a19b..2f3bf3bbbd77 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -4886,8 +4886,8 @@ static void update_pmu_cap(struct x86_hybrid_pmu *pmu) if (ebx & ARCH_PERFMON_EXT_EQ) pmu->config_mask |= ARCH_PERFMON_EVENTSEL_EQ;
- if (sub_bitmaps & ARCH_PERFMON_NUM_COUNTER_LEAF_BIT) { - cpuid_count(ARCH_PERFMON_EXT_LEAF, ARCH_PERFMON_NUM_COUNTER_LEAF, + if (sub_bitmaps & ARCH_PERFMON_NUM_COUNTER_LEAF) { + cpuid_count(ARCH_PERFMON_EXT_LEAF, ARCH_PERFMON_NUM_COUNTER_LEAF_BIT, &eax, &ebx, &ecx, &edx); pmu->cntr_mask64 = eax; pmu->fixed_cntr_mask64 = ebx; diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h index 91b73571412f..41ace8431e01 100644 --- a/arch/x86/include/asm/perf_event.h +++ b/arch/x86/include/asm/perf_event.h @@ -190,7 +190,7 @@ union cpuid10_edx { #define ARCH_PERFMON_EXT_UMASK2 0x1 #define ARCH_PERFMON_EXT_EQ 0x2 #define ARCH_PERFMON_NUM_COUNTER_LEAF_BIT 0x1 -#define ARCH_PERFMON_NUM_COUNTER_LEAF 0x1 +#define ARCH_PERFMON_NUM_COUNTER_LEAF BIT(ARCH_PERFMON_NUM_COUNTER_LEAF_BIT)
/* * Intel Architectural LBR CPUID detection/enumeration details: