ARMv8.5-PMU introduces 64-bit event counters, however KVM doesn't yet support this. Let's trap the Debug Feature Registers in order to limit PMUVer/PerfMon in the Debug Feature Registers to PMUv3 for ARMv8.4.
Signed-off-by: Andrew Murray <[email protected]> Reviewed-by: Suzuki K Poulose <[email protected]> --- arch/arm64/include/asm/sysreg.h | 5 +++++ arch/arm64/kvm/sys_regs.c | 11 +++++++++++ 2 files changed, 16 insertions(+) diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 6e919fafb43d..d969df417f88 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -672,6 +672,11 @@ #define ID_AA64DFR0_TRACEVER_SHIFT 4 #define ID_AA64DFR0_DEBUGVER_SHIFT 0 +#define ID_DFR0_PERFMON_SHIFT 24 + +#define ID_DFR0_EL1_PMUVER_8_4 5 +#define ID_AA64DFR0_EL1_PMUVER_8_4 5 + #define ID_ISAR5_RDM_SHIFT 24 #define ID_ISAR5_CRC32_SHIFT 16 #define ID_ISAR5_SHA2_SHIFT 12 diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 9f2165937f7d..028c93a88a51 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1085,6 +1085,17 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, (0xfUL << ID_AA64ISAR1_API_SHIFT) | (0xfUL << ID_AA64ISAR1_GPA_SHIFT) | (0xfUL << ID_AA64ISAR1_GPI_SHIFT)); + } else if (id == SYS_ID_AA64DFR0_EL1) { + /* Limit guests to PMUv3 for ARMv8.4 */ + val = cpuid_feature_cap_signed_field_width(val, + ID_AA64DFR0_PMUVER_SHIFT, + 4, ID_AA64DFR0_EL1_PMUVER_8_4); + } else if (id == SYS_ID_DFR0_EL1) { + /* Limit guests to PMUv3 for ARMv8.4 */ + val = cpuid_feature_cap_signed_field_width(val, + ID_DFR0_PERFMON_SHIFT, + 4, ID_DFR0_EL1_PMUVER_8_4); + } return val; -- 2.21.0 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
