Merge branch 'errata/tx2-219' into for-next/fixes

Workaround for Cavium/Marvell ThunderX2 erratum #219.

* errata/tx2-219:
  arm64: Allow CAVIUM_TX2_ERRATUM_219 to be selected
  arm64: Avoid Cavium TX2 erratum 219 when switching TTBR
  arm64: Enable workaround for Cavium TX2 erratum 219 when running SMT
  arm64: KVM: Trap VM ops when ARM64_WORKAROUND_CAVIUM_TX2_219_TVM is set

1 files changed, 69 insertions, 17 deletions

diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index bd978ad71936..799e84a40335 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -124,6 +124,9 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
 {
 	u64 hcr = vcpu->arch.hcr_el2;
 
+	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM))
+		hcr |= HCR_TVM;
+
 	write_sysreg(hcr, hcr_el2);
 
 	if (cpus_have_const_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE))
@@ -174,8 +177,10 @@ static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu)
 	 * the crucial bit is "On taking a vSError interrupt,
 	 * HCR_EL2.VSE is cleared to 0."
 	 */
-	if (vcpu->arch.hcr_el2 & HCR_VSE)
-		vcpu->arch.hcr_el2 = read_sysreg(hcr_el2);
+	if (vcpu->arch.hcr_el2 & HCR_VSE) {
+		vcpu->arch.hcr_el2 &= ~HCR_VSE;
+		vcpu->arch.hcr_el2 |= read_sysreg(hcr_el2) & HCR_VSE;
+	}
 
 	if (has_vhe())
 		deactivate_traps_vhe();
@@ -229,20 +234,6 @@ static void __hyp_text __hyp_vgic_restore_state(struct kvm_vcpu *vcpu)
 	}
 }
 
-static bool __hyp_text __true_value(void)
-{
-	return true;
-}
-
-static bool __hyp_text __false_value(void)
-{
-	return false;
-}
-
-static hyp_alternate_select(__check_arm_834220,
-			    __false_value, __true_value,
-			    ARM64_WORKAROUND_834220);
-
 static bool __hyp_text __translate_far_to_hpfar(u64 far, u64 *hpfar)
 {
 	u64 par, tmp;
@@ -298,7 +289,8 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
 	 * resolve the IPA using the AT instruction.
 	 */
 	if (!(esr & ESR_ELx_S1PTW) &&
-	    (__check_arm_834220()() || (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
+	    (cpus_have_const_cap(ARM64_WORKAROUND_834220) ||
+	     (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
 		if (!__translate_far_to_hpfar(far, &hpfar))
 			return false;
 	} else {
@@ -393,6 +385,61 @@ static bool __hyp_text __hyp_handle_fpsimd(struct kvm_vcpu *vcpu)
 	return true;
 }
 
+static bool __hyp_text handle_tx2_tvm(struct kvm_vcpu *vcpu)
+{
+	u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_hsr(vcpu));
+	int rt = kvm_vcpu_sys_get_rt(vcpu);
+	u64 val = vcpu_get_reg(vcpu, rt);
+
+	/*
+	 * The normal sysreg handling code expects to see the traps,
+	 * let's not do anything here.
+	 */
+	if (vcpu->arch.hcr_el2 & HCR_TVM)
+		return false;
+
+	switch (sysreg) {
+	case SYS_SCTLR_EL1:
+		write_sysreg_el1(val, SYS_SCTLR);
+		break;
+	case SYS_TTBR0_EL1:
+		write_sysreg_el1(val, SYS_TTBR0);
+		break;
+	case SYS_TTBR1_EL1:
+		write_sysreg_el1(val, SYS_TTBR1);
+		break;
+	case SYS_TCR_EL1:
+		write_sysreg_el1(val, SYS_TCR);
+		break;
+	case SYS_ESR_EL1:
+		write_sysreg_el1(val, SYS_ESR);
+		break;
+	case SYS_FAR_EL1:
+		write_sysreg_el1(val, SYS_FAR);
+		break;
+	case SYS_AFSR0_EL1:
+		write_sysreg_el1(val, SYS_AFSR0);
+		break;
+	case SYS_AFSR1_EL1:
+		write_sysreg_el1(val, SYS_AFSR1);
+		break;
+	case SYS_MAIR_EL1:
+		write_sysreg_el1(val, SYS_MAIR);
+		break;
+	case SYS_AMAIR_EL1:
+		write_sysreg_el1(val, SYS_AMAIR);
+		break;
+	case SYS_CONTEXTIDR_EL1:
+		write_sysreg_el1(val, SYS_CONTEXTIDR);
+		break;
+	default:
+		return false;
+	}
+
+	__kvm_skip_instr(vcpu);
+	return true;
+}
+
 /*
  * Return true when we were able to fixup the guest exit and should return to
  * the guest, false when we should restore the host state and return to the
@@ -412,6 +459,11 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
 	if (*exit_code != ARM_EXCEPTION_TRAP)
 		goto exit;
 
+	if (cpus_have_const_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) &&
+	    kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 &&
+	    handle_tx2_tvm(vcpu))
+		return true;
+
 	/*
 	 * We trap the first access to the FP/SIMD to save the host context
 	 * and restore the guest context lazily.