[PATCH v6 21/25] KVM: arm64: Trap disabled features of ID_AA64DFR0_EL1

[Reiji Watanabe]

Add feature_config_ctrl for PMUv3, PMS and TraceFilt, which are
indicated in ID_AA64DFR0_EL1, to program configuration registers
to trap guest's using those features when they are not exposed to
the guest.

Signed-off-by: Reiji Watanabe <reijiw at google.com>
---
 arch/arm64/kvm/sys_regs.c | 64 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 924ffedf4b05..677815030d44 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -350,6 +350,30 @@ static void feature_mte_trap_activate(struct kvm_vcpu *vcpu)
 	feature_trap_activate(vcpu, VCPU_HCR_EL2, HCR_TID5, HCR_DCT | HCR_ATA);
 }
 
+static void feature_trace_trap_activate(struct kvm_vcpu *vcpu)
+{
+	if (has_vhe())
+		feature_trap_activate(vcpu, VCPU_CPTR_EL2, CPACR_EL1_TTA, 0);
+	else
+		feature_trap_activate(vcpu, VCPU_CPTR_EL2, CPTR_EL2_TTA, 0);
+}
+
+static void feature_pmuv3_trap_activate(struct kvm_vcpu *vcpu)
+{
+	feature_trap_activate(vcpu, VCPU_MDCR_EL2, MDCR_EL2_TPM, 0);
+}
+
+static void feature_pms_trap_activate(struct kvm_vcpu *vcpu)
+{
+	feature_trap_activate(vcpu, VCPU_MDCR_EL2, MDCR_EL2_TPMS,
+			      MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT);
+}
+
+static void feature_tracefilt_trap_activate(struct kvm_vcpu *vcpu)
+{
+	feature_trap_activate(vcpu, VCPU_MDCR_EL2, MDCR_EL2_TTRF, 0);
+}
+
 /* For ID_AA64PFR0_EL1 */
 static struct feature_config_ctrl ftr_ctrl_ras = {
 	.ftr_reg = SYS_ID_AA64PFR0_EL1,
@@ -376,6 +400,39 @@ static struct feature_config_ctrl ftr_ctrl_mte = {
 	.trap_activate = feature_mte_trap_activate,
 };
 
+/* For ID_AA64DFR0_EL1 */
+static struct feature_config_ctrl ftr_ctrl_trace = {
+	.ftr_reg = SYS_ID_AA64DFR0_EL1,
+	.ftr_shift = ID_AA64DFR0_TRACEVER_SHIFT,
+	.ftr_min = 1,
+	.ftr_signed = FTR_UNSIGNED,
+	.trap_activate = feature_trace_trap_activate,
+};
+
+static struct feature_config_ctrl ftr_ctrl_pmuv3 = {
+	.ftr_reg = SYS_ID_AA64DFR0_EL1,
+	.ftr_shift = ID_AA64DFR0_PMUVER_SHIFT,
+	.ftr_min = ID_AA64DFR0_PMUVER_8_0,
+	.ftr_signed = FTR_UNSIGNED,
+	.trap_activate = feature_pmuv3_trap_activate,
+};
+
+static struct feature_config_ctrl ftr_ctrl_pms = {
+	.ftr_reg = SYS_ID_AA64DFR0_EL1,
+	.ftr_shift = ID_AA64DFR0_PMSVER_SHIFT,
+	.ftr_min = ID_AA64DFR0_PMSVER_8_2,
+	.ftr_signed = FTR_UNSIGNED,
+	.trap_activate = feature_pms_trap_activate,
+};
+
+static struct feature_config_ctrl ftr_ctrl_tracefilt = {
+	.ftr_reg = SYS_ID_AA64DFR0_EL1,
+	.ftr_shift = ID_AA64DFR0_TRACE_FILT_SHIFT,
+	.ftr_min = 1,
+	.ftr_signed = FTR_UNSIGNED,
+	.trap_activate = feature_tracefilt_trap_activate,
+};
+
 /* id_reg_desc flags field values */
 #define ID_DESC_REG_UNALLOC	(1UL << 0)
 #define ID_DESC_REG_HIDDEN	(1UL << 1)
@@ -3733,6 +3790,13 @@ static struct id_reg_desc id_aa64dfr0_el1_desc = {
 	.init = init_id_aa64dfr0_el1_desc,
 	.validate = validate_id_aa64dfr0_el1,
 	.vcpu_mask = vcpu_mask_id_aa64dfr0_el1,
+	.trap_features = &(const struct feature_config_ctrl *[]) {
+		&ftr_ctrl_trace,
+		&ftr_ctrl_pmuv3,
+		&ftr_ctrl_pms,
+		&ftr_ctrl_tracefilt,
+		NULL,
+	},
 };
 
 static struct id_reg_desc id_dfr0_el1_desc = {
-- 
2.35.1.723.g4982287a31-goog