Merge branch 'kvm-arm64/ptrauth-fixes' into kvmarm-master/next

Signed-off-by: Marc Zyngier <maz@kernel.org>

3 files changed, 69 insertions, 6 deletions

diff --git a/arch/arm64/kvm/hyp/debug-sr.c b/arch/arm64/kvm/hyp/debug-sr.c
index 0fc9872a1467..e95af204fec7 100644
--- a/arch/arm64/kvm/hyp/debug-sr.c
+++ b/arch/arm64/kvm/hyp/debug-sr.c
@@ -185,7 +185,7 @@ void __hyp_text __debug_switch_to_guest(struct kvm_vcpu *vcpu)
 	if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
 		return;
 
-	host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 	guest_ctxt = &vcpu->arch.ctxt;
 	host_dbg = &vcpu->arch.host_debug_state.regs;
 	guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
@@ -207,7 +207,7 @@ void __hyp_text __debug_switch_to_host(struct kvm_vcpu *vcpu)
 	if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY))
 		return;
 
-	host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 	guest_ctxt = &vcpu->arch.ctxt;
 	host_dbg = &vcpu->arch.host_debug_state.regs;
 	guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index c07a45643cd4..1853c1788e0c 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -490,6 +490,64 @@ static bool __hyp_text handle_tx2_tvm(struct kvm_vcpu *vcpu)
 	return true;
 }
 
+static bool __hyp_text esr_is_ptrauth_trap(u32 esr)
+{
+	u32 ec = ESR_ELx_EC(esr);
+
+	if (ec == ESR_ELx_EC_PAC)
+		return true;
+
+	if (ec != ESR_ELx_EC_SYS64)
+		return false;
+
+	switch (esr_sys64_to_sysreg(esr)) {
+	case SYS_APIAKEYLO_EL1:
+	case SYS_APIAKEYHI_EL1:
+	case SYS_APIBKEYLO_EL1:
+	case SYS_APIBKEYHI_EL1:
+	case SYS_APDAKEYLO_EL1:
+	case SYS_APDAKEYHI_EL1:
+	case SYS_APDBKEYLO_EL1:
+	case SYS_APDBKEYHI_EL1:
+	case SYS_APGAKEYLO_EL1:
+	case SYS_APGAKEYHI_EL1:
+		return true;
+	}
+
+	return false;
+}
+
+#define __ptrauth_save_key(regs, key)						\
+({										\
+	regs[key ## KEYLO_EL1] = read_sysreg_s(SYS_ ## key ## KEYLO_EL1);	\
+	regs[key ## KEYHI_EL1] = read_sysreg_s(SYS_ ## key ## KEYHI_EL1);	\
+})
+
+static bool __hyp_text __hyp_handle_ptrauth(struct kvm_vcpu *vcpu)
+{
+	struct kvm_cpu_context *ctxt;
+	u64 val;
+
+	if (!vcpu_has_ptrauth(vcpu) ||
+	    !esr_is_ptrauth_trap(kvm_vcpu_get_hsr(vcpu)))
+		return false;
+
+	ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
+	__ptrauth_save_key(ctxt->sys_regs, APIA);
+	__ptrauth_save_key(ctxt->sys_regs, APIB);
+	__ptrauth_save_key(ctxt->sys_regs, APDA);
+	__ptrauth_save_key(ctxt->sys_regs, APDB);
+	__ptrauth_save_key(ctxt->sys_regs, APGA);
+
+	vcpu_ptrauth_enable(vcpu);
+
+	val = read_sysreg(hcr_el2);
+	val |= (HCR_API | HCR_APK);
+	write_sysreg(val, hcr_el2);
+
+	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
@@ -524,6 +582,9 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
 	if (__hyp_handle_fpsimd(vcpu))
 		return true;
 
+	if (__hyp_handle_ptrauth(vcpu))
+		return true;
+
 	if (!__populate_fault_info(vcpu))
 		return true;
 
@@ -642,7 +703,7 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
 	struct kvm_cpu_context *guest_ctxt;
 	u64 exit_code;
 
-	host_ctxt = vcpu->arch.host_cpu_context;
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 	host_ctxt->__hyp_running_vcpu = vcpu;
 	guest_ctxt = &vcpu->arch.ctxt;
 
@@ -747,7 +808,7 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
 
 	vcpu = kern_hyp_va(vcpu);
 
-	host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 	host_ctxt->__hyp_running_vcpu = vcpu;
 	guest_ctxt = &vcpu->arch.ctxt;
 
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index 0d60e6ee96b2..4fe528c570cf 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c
@@ -263,12 +263,13 @@ void __hyp_text __sysreg32_restore_state(struct kvm_vcpu *vcpu)
  */
 void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu)
 {
-	struct kvm_cpu_context *host_ctxt = vcpu->arch.host_cpu_context;
 	struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt;
+	struct kvm_cpu_context *host_ctxt;
 
 	if (!has_vhe())
 		return;
 
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 	__sysreg_save_user_state(host_ctxt);
 
 	/*
@@ -299,12 +300,13 @@ void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu)
  */
 void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu)
 {
-	struct kvm_cpu_context *host_ctxt = vcpu->arch.host_cpu_context;
 	struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt;
+	struct kvm_cpu_context *host_ctxt;
 
 	if (!has_vhe())
 		return;
 
+	host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt;
 	deactivate_traps_vhe_put();
 
 	__sysreg_save_el1_state(guest_ctxt);