On Thu, Jan 23, 2025 at 02:07:03PM +0000, Dapeng Mi wrote:
> From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
>
> 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@xxxxxxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> 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 5e8521a54474..12eb96219740 100644
> --- a/arch/x86/events/intel/core.c
> +++ b/arch/x86/events/intel/core.c
> @@ -4966,8 +4966,8 @@ 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 adaeb8ca3a8a..71e2ae021374 100644
> --- a/arch/x86/include/asm/perf_event.h
> +++ b/arch/x86/include/asm/perf_event.h
> @@ -197,7 +197,7 @@ 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)
if you'll look around, you'll note this file uses BIT_ULL(), please stay
consistent.
