4 files changed, 14 insertions, 76 deletions

diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
index 00d422336a45..f39801e4136c 100644
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@ -236,24 +236,3 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu)
 		}
 	}
 }
-
-
-/*
- * After successfully emulating an instruction, we might want to
- * return to user space with a KVM_EXIT_DEBUG. We can only do this
- * once the emulation is complete, though, so for userspace emulations
- * we have to wait until we have re-entered KVM before calling this
- * helper.
- *
- * Return true (and set exit_reason) to return to userspace or false
- * if no further action is required.
- */
-bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run)
-{
-	if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
-		run->exit_reason = KVM_EXIT_DEBUG;
-		run->debug.arch.hsr = ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT;
-		return true;
-	}
-	return false;
-}
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 35a81bebd02b..b0643f9c4873 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -229,13 +229,6 @@ static int handle_trap_exceptions(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		handled = exit_handler(vcpu, run);
 	}
 
-	/*
-	 * kvm_arm_handle_step_debug() sets the exit_reason on the kvm_run
-	 * structure if we need to return to userspace.
-	 */
-	if (handled > 0 && kvm_arm_handle_step_debug(vcpu, run))
-		handled = 0;
-
 	return handled;
 }
 
@@ -269,12 +262,7 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
 	case ARM_EXCEPTION_IRQ:
 		return 1;
 	case ARM_EXCEPTION_EL1_SERROR:
-		/* We may still need to return for single-step */
-		if (!(*vcpu_cpsr(vcpu) & DBG_SPSR_SS)
-			&& kvm_arm_handle_step_debug(vcpu, run))
-			return 0;
-		else
-			return 1;
+		return 1;
 	case ARM_EXCEPTION_TRAP:
 		return handle_trap_exceptions(vcpu, run);
 	case ARM_EXCEPTION_HYP_GONE:
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 7cc175c88a37..4282f05771c1 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -305,33 +305,6 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
 	return true;
 }
 
-/* Skip an instruction which has been emulated. Returns true if
- * execution can continue or false if we need to exit hyp mode because
- * single-step was in effect.
- */
-static bool __hyp_text __skip_instr(struct kvm_vcpu *vcpu)
-{
-	*vcpu_pc(vcpu) = read_sysreg_el2(elr);
-
-	if (vcpu_mode_is_32bit(vcpu)) {
-		vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(spsr);
-		kvm_skip_instr32(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
-		write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, spsr);
-	} else {
-		*vcpu_pc(vcpu) += 4;
-	}
-
-	write_sysreg_el2(*vcpu_pc(vcpu), elr);
-
-	if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
-		vcpu->arch.fault.esr_el2 =
-			(ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT) | 0x22;
-		return false;
-	} else {
-		return true;
-	}
-}
-
 static bool __hyp_text __hyp_switch_fpsimd(struct kvm_vcpu *vcpu)
 {
 	struct user_fpsimd_state *host_fpsimd = vcpu->arch.host_fpsimd_state;
@@ -420,20 +393,12 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
 		if (valid) {
 			int ret = __vgic_v2_perform_cpuif_access(vcpu);
 
-			if (ret ==  1 && __skip_instr(vcpu))
+			if (ret == 1)
 				return true;
 
-			if (ret == -1) {
-				/* Promote an illegal access to an
-				 * SError. If we would be returning
-				 * due to single-step clear the SS
-				 * bit so handle_exit knows what to
-				 * do after dealing with the error.
-				 */
-				if (!__skip_instr(vcpu))
-					*vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
+			/* Promote an illegal access to an SError.*/
+			if (ret == -1)
 				*exit_code = ARM_EXCEPTION_EL1_SERROR;
-			}
 
 			goto exit;
 		}
@@ -444,7 +409,7 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
 	     kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) {
 		int ret = __vgic_v3_perform_cpuif_access(vcpu);
 
-		if (ret == 1 && __skip_instr(vcpu))
+		if (ret == 1)
 			return true;
 	}
 
diff --git a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
index 215c7c0eb3b0..9cbdd034a563 100644
--- a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
+++ b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
@@ -41,7 +41,7 @@ static bool __hyp_text __is_be(struct kvm_vcpu *vcpu)
  * Returns:
  *  1: GICV access successfully performed
  *  0: Not a GICV access
- * -1: Illegal GICV access
+ * -1: Illegal GICV access successfully performed
  */
 int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
 {
@@ -61,12 +61,16 @@ int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
 		return 0;
 
 	/* Reject anything but a 32bit access */
-	if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32))
+	if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32)) {
+		__kvm_skip_instr(vcpu);
 		return -1;
+	}
 
 	/* Not aligned? Don't bother */
-	if (fault_ipa & 3)
+	if (fault_ipa & 3) {
+		__kvm_skip_instr(vcpu);
 		return -1;
+	}
 
 	rd = kvm_vcpu_dabt_get_rd(vcpu);
 	addr  = hyp_symbol_addr(kvm_vgic_global_state)->vcpu_hyp_va;
@@ -88,5 +92,7 @@ int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
 		vcpu_set_reg(vcpu, rd, data);
 	}
 
+	__kvm_skip_instr(vcpu);
+
 	return 1;
 }