[PATCH v4 10/18] KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN

Oliver Upton posted 18 patches 1 month ago
[PATCH v4 10/18] KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN
Posted by Oliver Upton 1 month ago
MDCR_EL2.HPMN splits the PMU event counters into two ranges: the first
range is accessible from all ELs, and the second range is accessible
only to EL2/3. Supposing the guest hypervisor allows direct access to
the PMU counters from the L2, KVM needs to locally handle those
accesses.

Add a new complex trap configuration for HPMN that checks if the counter
index is accessible to the current context. As written, the architecture
suggests HPMN only causes PMEVCNTR<n>_EL0 to trap, though intuition (and
the pseudocode) suggest that the trap applies to PMEVTYPER<n>_EL0 as
well.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
---
 arch/arm64/kvm/emulate-nested.c | 160 +++++++++++++++++++-------------
 arch/arm64/kvm/pmu-emul.c       |  18 ++++
 include/kvm/arm_pmu.h           |   6 ++
 3 files changed, 120 insertions(+), 64 deletions(-)

diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c
index f9594296d69c..162bddbfbe79 100644
--- a/arch/arm64/kvm/emulate-nested.c
+++ b/arch/arm64/kvm/emulate-nested.c
@@ -110,6 +110,7 @@ enum cgt_group_id {
 	CGT_HCR_TPU_TOCU,
 	CGT_HCR_NV1_nNV2_ENSCXT,
 	CGT_MDCR_TPM_TPMCR,
+	CGT_MDCR_TPM_HPMN,
 	CGT_MDCR_TDE_TDA,
 	CGT_MDCR_TDE_TDOSA,
 	CGT_MDCR_TDE_TDRA,
@@ -126,6 +127,7 @@ enum cgt_group_id {
 	CGT_CNTHCTL_EL1PTEN,
 
 	CGT_CPTR_TTA,
+	CGT_MDCR_HPMN,
 
 	/* Must be last */
 	__NR_CGT_GROUP_IDS__
@@ -441,6 +443,7 @@ static const enum cgt_group_id *coarse_control_combo[] = {
 	MCB(CGT_HCR_TPU_TOCU,		CGT_HCR_TPU, CGT_HCR_TOCU),
 	MCB(CGT_HCR_NV1_nNV2_ENSCXT,	CGT_HCR_NV1_nNV2, CGT_HCR_ENSCXT),
 	MCB(CGT_MDCR_TPM_TPMCR,		CGT_MDCR_TPM, CGT_MDCR_TPMCR),
+	MCB(CGT_MDCR_TPM_HPMN,		CGT_MDCR_TPM, CGT_MDCR_HPMN),
 	MCB(CGT_MDCR_TDE_TDA,		CGT_MDCR_TDE, CGT_MDCR_TDA),
 	MCB(CGT_MDCR_TDE_TDOSA,		CGT_MDCR_TDE, CGT_MDCR_TDOSA),
 	MCB(CGT_MDCR_TDE_TDRA,		CGT_MDCR_TDE, CGT_MDCR_TDRA),
@@ -504,6 +507,34 @@ static enum trap_behaviour check_cptr_tta(struct kvm_vcpu *vcpu)
 	return BEHAVE_HANDLE_LOCALLY;
 }
 
+static enum trap_behaviour check_mdcr_hpmn(struct kvm_vcpu *vcpu)
+{
+	u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
+	unsigned int idx;
+
+
+	switch (sysreg) {
+	case SYS_PMEVTYPERn_EL0(0) ... SYS_PMEVTYPERn_EL0(30):
+	case SYS_PMEVCNTRn_EL0(0) ... SYS_PMEVCNTRn_EL0(30):
+		idx = (sys_reg_CRm(sysreg) & 0x3) << 3 | sys_reg_Op2(sysreg);
+		break;
+	case SYS_PMXEVTYPER_EL0:
+	case SYS_PMXEVCNTR_EL0:
+		idx = SYS_FIELD_GET(PMSELR_EL0, SEL,
+				    __vcpu_sys_reg(vcpu, PMSELR_EL0));
+		break;
+	default:
+		/* Someone used this trap helper for something else... */
+		KVM_BUG_ON(1, vcpu->kvm);
+		return BEHAVE_HANDLE_LOCALLY;
+	}
+
+	if (kvm_pmu_counter_is_hyp(vcpu, idx))
+		return BEHAVE_FORWARD_RW | BEHAVE_IN_HOST_EL0;
+
+	return BEHAVE_HANDLE_LOCALLY;
+}
+
 #define CCC(id, fn)				\
 	[id - __COMPLEX_CONDITIONS__] = fn
 
@@ -511,6 +542,7 @@ static const complex_condition_check ccc[] = {
 	CCC(CGT_CNTHCTL_EL1PCTEN, check_cnthctl_el1pcten),
 	CCC(CGT_CNTHCTL_EL1PTEN, check_cnthctl_el1pten),
 	CCC(CGT_CPTR_TTA, check_cptr_tta),
+	CCC(CGT_MDCR_HPMN, check_mdcr_hpmn),
 };
 
 /*
@@ -925,77 +957,77 @@ static const struct encoding_to_trap_config encoding_to_cgt[] __initconst = {
 	SR_TRAP(SYS_PMOVSCLR_EL0,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_PMCEID0_EL0,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_PMCEID1_EL0,	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMXEVTYPER_EL0,	CGT_MDCR_TPM),
+	SR_TRAP(SYS_PMXEVTYPER_EL0,	CGT_MDCR_TPM_HPMN),
 	SR_TRAP(SYS_PMSWINC_EL0,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_PMSELR_EL0,		CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMXEVCNTR_EL0,	CGT_MDCR_TPM),
+	SR_TRAP(SYS_PMXEVCNTR_EL0,	CGT_MDCR_TPM_HPMN),
 	SR_TRAP(SYS_PMCCNTR_EL0,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_PMUSERENR_EL0,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_PMINTENSET_EL1,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_PMINTENCLR_EL1,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_PMMIR_EL1,		CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(0),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(1),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(2),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(3),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(4),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(5),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(6),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(7),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(8),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(9),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(10),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(11),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(12),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(13),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(14),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(15),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(16),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(17),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(18),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(19),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(20),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(21),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(22),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(23),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(24),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(25),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(26),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(27),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(28),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(29),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVCNTRn_EL0(30),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(0),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(1),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(2),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(3),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(4),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(5),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(6),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(7),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(8),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(9),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(10),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(11),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(12),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(13),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(14),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(15),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(16),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(17),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(18),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(19),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(20),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(21),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(22),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(23),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(24),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(25),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(26),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(27),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(28),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(29),	CGT_MDCR_TPM),
-	SR_TRAP(SYS_PMEVTYPERn_EL0(30),	CGT_MDCR_TPM),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(0),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(1),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(2),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(3),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(4),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(5),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(6),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(7),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(8),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(9),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(10),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(11),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(12),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(13),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(14),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(15),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(16),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(17),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(18),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(19),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(20),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(21),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(22),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(23),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(24),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(25),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(26),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(27),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(28),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(29),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVCNTRn_EL0(30),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(0),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(1),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(2),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(3),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(4),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(5),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(6),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(7),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(8),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(9),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(10),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(11),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(12),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(13),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(14),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(15),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(16),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(17),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(18),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(19),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(20),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(21),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(22),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(23),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(24),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(25),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(26),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(27),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(28),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(29),	CGT_MDCR_TPM_HPMN),
+	SR_TRAP(SYS_PMEVTYPERn_EL0(30),	CGT_MDCR_TPM_HPMN),
 	SR_TRAP(SYS_PMCCFILTR_EL0,	CGT_MDCR_TPM),
 	SR_TRAP(SYS_MDCCSR_EL0,		CGT_MDCR_TDCC_TDE_TDA),
 	SR_TRAP(SYS_MDCCINT_EL1,	CGT_MDCR_TDCC_TDE_TDA),
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index ac36c438b8c1..28f938f145ac 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -265,6 +265,24 @@ void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu)
 	irq_work_sync(&vcpu->arch.pmu.overflow_work);
 }
 
+bool kvm_pmu_counter_is_hyp(struct kvm_vcpu *vcpu, unsigned int idx)
+{
+	unsigned int hpmn;
+
+	if (!vcpu_has_nv(vcpu) || idx == ARMV8_PMU_CYCLE_IDX)
+		return false;
+
+	/*
+	 * Programming HPMN=0 is CONSTRAINED UNPREDICTABLE if FEAT_HPMN0 isn't
+	 * implemented. Since KVM's ability to emulate HPMN=0 does not directly
+	 * depend on hardware (all PMU registers are trapped), make the
+	 * implementation choice that all counters are included in the second
+	 * range reserved for EL2/EL3.
+	 */
+	hpmn = SYS_FIELD_GET(MDCR_EL2, HPMN, __vcpu_sys_reg(vcpu, MDCR_EL2));
+	return idx >= hpmn;
+}
+
 u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu)
 {
 	u64 val = FIELD_GET(ARMV8_PMU_PMCR_N, kvm_vcpu_read_pmcr(vcpu));
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index e08aeec5d936..e6103df9ef5d 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -96,6 +96,7 @@ int kvm_arm_set_default_pmu(struct kvm *kvm);
 u8 kvm_arm_pmu_get_max_counters(struct kvm *kvm);
 
 u64 kvm_vcpu_read_pmcr(struct kvm_vcpu *vcpu);
+bool kvm_pmu_counter_is_hyp(struct kvm_vcpu *vcpu, unsigned int idx);
 #else
 struct kvm_pmu {
 };
@@ -187,6 +188,11 @@ static inline u64 kvm_vcpu_read_pmcr(struct kvm_vcpu *vcpu)
 	return 0;
 }
 
+static inline bool kvm_pmu_counter_is_hyp(struct kvm_vcpu *vcpu)
+{
+	return false;
+}
+
 #endif
 
 #endif
-- 
2.47.0.163.g1226f6d8fa-goog
Re: [PATCH v4 10/18] KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN
Posted by Oliver Upton 1 month ago
On Fri, Oct 25, 2024 at 06:23:45PM +0000, Oliver Upton wrote:
> MDCR_EL2.HPMN splits the PMU event counters into two ranges: the first
> range is accessible from all ELs, and the second range is accessible
> only to EL2/3. Supposing the guest hypervisor allows direct access to
> the PMU counters from the L2, KVM needs to locally handle those
> accesses.
> 
> Add a new complex trap configuration for HPMN that checks if the counter
> index is accessible to the current context. As written, the architecture
> suggests HPMN only causes PMEVCNTR<n>_EL0 to trap, though intuition (and
> the pseudocode) suggest that the trap applies to PMEVTYPER<n>_EL0 as
> well.
> 
> Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
> ---
>  arch/arm64/kvm/emulate-nested.c | 160 +++++++++++++++++++-------------
>  arch/arm64/kvm/pmu-emul.c       |  18 ++++
>  include/kvm/arm_pmu.h           |   6 ++
>  3 files changed, 120 insertions(+), 64 deletions(-)

Gonna squash in the following to fix !CONFIG_HW_PERF_EVENTS builds.

diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index e6103df9ef5d..feb5d1d35f0f 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -188,7 +188,7 @@ static inline u64 kvm_vcpu_read_pmcr(struct kvm_vcpu *vcpu)
 	return 0;
 }
 
-static inline bool kvm_pmu_counter_is_hyp(struct kvm_vcpu *vcpu)
+static inline bool kvm_pmu_counter_is_hyp(struct kvm_vcpu *vcpu, unsigned int idx)
 {
 	return false;
 }

-- 
Thanks,
Oliver
Re: [PATCH v4 10/18] KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN
Posted by kernel test robot 1 month ago
Hi Oliver,

kernel test robot noticed the following build errors:

[auto build test ERROR on 8e929cb546ee42c9a61d24fae60605e9e3192354]

url:    https://github.com/intel-lab-lkp/linux/commits/Oliver-Upton/KVM-arm64-Extend-masking-facility-to-arbitrary-registers/20241026-023055
base:   8e929cb546ee42c9a61d24fae60605e9e3192354
patch link:    https://lore.kernel.org/r/20241025182354.3364124-11-oliver.upton%40linux.dev
patch subject: [PATCH v4 10/18] KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN
config: arm64-randconfig-004-20241026 (https://download.01.org/0day-ci/archive/20241026/202410261839.enJ68VEv-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241026/202410261839.enJ68VEv-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410261839.enJ68VEv-lkp@intel.com/

All errors (new ones prefixed by >>):

   arch/arm64/kvm/emulate-nested.c: In function 'check_mdcr_hpmn':
>> arch/arm64/kvm/emulate-nested.c:532:13: error: too many arguments to function 'kvm_pmu_counter_is_hyp'
     532 |         if (kvm_pmu_counter_is_hyp(vcpu, idx))
         |             ^~~~~~~~~~~~~~~~~~~~~~
   In file included from arch/arm64/include/asm/kvm_host.h:38,
                    from include/linux/kvm_host.h:45,
                    from arch/arm64/kvm/emulate-nested.c:8:
   include/kvm/arm_pmu.h:191:20: note: declared here
     191 | static inline bool kvm_pmu_counter_is_hyp(struct kvm_vcpu *vcpu)
         |                    ^~~~~~~~~~~~~~~~~~~~~~


vim +/kvm_pmu_counter_is_hyp +532 arch/arm64/kvm/emulate-nested.c

   509	
   510	static enum trap_behaviour check_mdcr_hpmn(struct kvm_vcpu *vcpu)
   511	{
   512		u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
   513		unsigned int idx;
   514	
   515	
   516		switch (sysreg) {
   517		case SYS_PMEVTYPERn_EL0(0) ... SYS_PMEVTYPERn_EL0(30):
   518		case SYS_PMEVCNTRn_EL0(0) ... SYS_PMEVCNTRn_EL0(30):
   519			idx = (sys_reg_CRm(sysreg) & 0x3) << 3 | sys_reg_Op2(sysreg);
   520			break;
   521		case SYS_PMXEVTYPER_EL0:
   522		case SYS_PMXEVCNTR_EL0:
   523			idx = SYS_FIELD_GET(PMSELR_EL0, SEL,
   524					    __vcpu_sys_reg(vcpu, PMSELR_EL0));
   525			break;
   526		default:
   527			/* Someone used this trap helper for something else... */
   528			KVM_BUG_ON(1, vcpu->kvm);
   529			return BEHAVE_HANDLE_LOCALLY;
   530		}
   531	
 > 532		if (kvm_pmu_counter_is_hyp(vcpu, idx))
   533			return BEHAVE_FORWARD_RW | BEHAVE_IN_HOST_EL0;
   534	
   535		return BEHAVE_HANDLE_LOCALLY;
   536	}
   537	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH v4 10/18] KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN
Posted by kernel test robot 1 month ago
Hi Oliver,

kernel test robot noticed the following build errors:

[auto build test ERROR on 8e929cb546ee42c9a61d24fae60605e9e3192354]

url:    https://github.com/intel-lab-lkp/linux/commits/Oliver-Upton/KVM-arm64-Extend-masking-facility-to-arbitrary-registers/20241026-023055
base:   8e929cb546ee42c9a61d24fae60605e9e3192354
patch link:    https://lore.kernel.org/r/20241025182354.3364124-11-oliver.upton%40linux.dev
patch subject: [PATCH v4 10/18] KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN
config: arm64-randconfig-003-20241026 (https://download.01.org/0day-ci/archive/20241026/202410261855.fvLOtls9-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 5886454669c3c9026f7f27eab13509dd0241f2d6)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241026/202410261855.fvLOtls9-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410261855.fvLOtls9-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from arch/arm64/kvm/emulate-nested.c:8:
   In file included from include/linux/kvm_host.h:16:
   In file included from include/linux/mm.h:2213:
   include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
     518 |         return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
         |                               ~~~~~~~~~~~ ^ ~~~
>> arch/arm64/kvm/emulate-nested.c:532:35: error: too many arguments to function call, expected single argument 'vcpu', have 2 arguments
     532 |         if (kvm_pmu_counter_is_hyp(vcpu, idx))
         |             ~~~~~~~~~~~~~~~~~~~~~~       ^~~
   include/kvm/arm_pmu.h:191:20: note: 'kvm_pmu_counter_is_hyp' declared here
     191 | static inline bool kvm_pmu_counter_is_hyp(struct kvm_vcpu *vcpu)
         |                    ^                      ~~~~~~~~~~~~~~~~~~~~~
   1 warning and 1 error generated.


vim +/vcpu +532 arch/arm64/kvm/emulate-nested.c

   509	
   510	static enum trap_behaviour check_mdcr_hpmn(struct kvm_vcpu *vcpu)
   511	{
   512		u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
   513		unsigned int idx;
   514	
   515	
   516		switch (sysreg) {
   517		case SYS_PMEVTYPERn_EL0(0) ... SYS_PMEVTYPERn_EL0(30):
   518		case SYS_PMEVCNTRn_EL0(0) ... SYS_PMEVCNTRn_EL0(30):
   519			idx = (sys_reg_CRm(sysreg) & 0x3) << 3 | sys_reg_Op2(sysreg);
   520			break;
   521		case SYS_PMXEVTYPER_EL0:
   522		case SYS_PMXEVCNTR_EL0:
   523			idx = SYS_FIELD_GET(PMSELR_EL0, SEL,
   524					    __vcpu_sys_reg(vcpu, PMSELR_EL0));
   525			break;
   526		default:
   527			/* Someone used this trap helper for something else... */
   528			KVM_BUG_ON(1, vcpu->kvm);
   529			return BEHAVE_HANDLE_LOCALLY;
   530		}
   531	
 > 532		if (kvm_pmu_counter_is_hyp(vcpu, idx))
   533			return BEHAVE_FORWARD_RW | BEHAVE_IN_HOST_EL0;
   534	
   535		return BEHAVE_HANDLE_LOCALLY;
   536	}
   537	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki