KVM: arm64: Drop unnecessary masking of PMU registers

We always sanitise our PMU sysreg on the write side, so there
is no need to do it on the read side as well.

Drop the unnecessary masking.
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210719123902.1493805-3-maz@kernel.org

arch/arm64/kvm/pmu-emul.c

@@ -373,7 +373,6 @@ static u64 kvm_pmu_overflow_status(struct kvm_vcpu *vcpu)
 		reg = __vcpu_sys_reg(vcpu, PMOVSSET_EL0);
 		reg &= __vcpu_sys_reg(vcpu, PMCNTENSET_EL0);
 		reg &= __vcpu_sys_reg(vcpu, PMINTENSET_EL1);
-		reg &= kvm_pmu_valid_counter_mask(vcpu);
 	}
 
 	return reg;
@@ -569,7 +568,7 @@ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val)
 
 	if (val & ARMV8_PMU_PMCR_E) {
 		kvm_pmu_enable_counter_mask(vcpu,
-		       __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask);
+		       __vcpu_sys_reg(vcpu, PMCNTENSET_EL0));
 	} else {
 		kvm_pmu_disable_counter_mask(vcpu, mask);
 	}

arch/arm64/kvm/sys_regs.c

@@ -880,7 +880,7 @@ static bool access_pmcnten(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 			kvm_pmu_disable_counter_mask(vcpu, val);
 		}
 	} else {
-		p->regval = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask;
+		p->regval = __vcpu_sys_reg(vcpu, PMCNTENSET_EL0);
 	}
 
 	return true;
@@ -904,7 +904,7 @@ static bool access_pminten(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 			/* accessing PMINTENCLR_EL1 */
 			__vcpu_sys_reg(vcpu, PMINTENSET_EL1) &= ~val;
 	} else {
-		p->regval = __vcpu_sys_reg(vcpu, PMINTENSET_EL1) & mask;
+		p->regval = __vcpu_sys_reg(vcpu, PMINTENSET_EL1);
 	}
 
 	return true;
@@ -926,7 +926,7 @@ static bool access_pmovs(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 			/* accessing PMOVSCLR_EL0 */
 			__vcpu_sys_reg(vcpu, PMOVSSET_EL0) &= ~(p->regval & mask);
 	} else {
-		p->regval = __vcpu_sys_reg(vcpu, PMOVSSET_EL0) & mask;
+		p->regval = __vcpu_sys_reg(vcpu, PMOVSSET_EL0);
 	}
 
 	return true;