Merge branch kvm-arm64/nv-trap-forwarding into kvmarm-master/next

* kvm-arm64/nv-trap-forwarding: (30 commits)
  : .
  : This implements the so called "trap forwarding" infrastructure, which
  : gets used when we take a trap from an L2 guest and that the L1 guest
  : wants to see the trap for itself.
  : .
  KVM: arm64: nv: Add trap description for SPSR_EL2 and ELR_EL2
  KVM: arm64: nv: Select XARRAY_MULTI to fix build error
  KVM: arm64: nv: Add support for HCRX_EL2
  KVM: arm64: Move HCRX_EL2 switch to load/put on VHE systems
  KVM: arm64: nv: Expose FGT to nested guests
  KVM: arm64: nv: Add switching support for HFGxTR/HDFGxTR
  KVM: arm64: nv: Expand ERET trap forwarding to handle FGT
  KVM: arm64: nv: Add SVC trap forwarding
  KVM: arm64: nv: Add trap forwarding for HDFGxTR_EL2
  KVM: arm64: nv: Add trap forwarding for HFGITR_EL2
  KVM: arm64: nv: Add trap forwarding for HFGxTR_EL2
  KVM: arm64: nv: Add fine grained trap forwarding infrastructure
  KVM: arm64: nv: Add trap forwarding for CNTHCTL_EL2
  KVM: arm64: nv: Add trap forwarding for MDCR_EL2
  KVM: arm64: nv: Expose FEAT_EVT to nested guests
  KVM: arm64: nv: Add trap forwarding for HCR_EL2
  KVM: arm64: nv: Add trap forwarding infrastructure
  KVM: arm64: Restructure FGT register switching
  KVM: arm64: nv: Add FGT registers
  KVM: arm64: Add missing HCR_EL2 trap bits
  ...

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

1 files changed, 28 insertions, 1 deletions

diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 6dcd6604b6bc..617ae6dea5d5 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -222,7 +222,33 @@ static int kvm_handle_eret(struct kvm_vcpu *vcpu)
 	if (kvm_vcpu_get_esr(vcpu) & ESR_ELx_ERET_ISS_ERET)
 		return kvm_handle_ptrauth(vcpu);
 
-	kvm_emulate_nested_eret(vcpu);
+	/*
+	 * If we got here, two possibilities:
+	 *
+	 * - the guest is in EL2, and we need to fully emulate ERET
+	 *
+	 * - the guest is in EL1, and we need to reinject the
+         *   exception into the L1 hypervisor.
+	 *
+	 * If KVM ever traps ERET for its own use, we'll have to
+	 * revisit this.
+	 */
+	if (is_hyp_ctxt(vcpu))
+		kvm_emulate_nested_eret(vcpu);
+	else
+		kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu));
+
+	return 1;
+}
+
+static int handle_svc(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * So far, SVC traps only for NV via HFGITR_EL2. A SVC from a
+	 * 32bit guest would be caught by vpcu_mode_is_bad_32bit(), so
+	 * we should only have to deal with a 64 bit exception.
+	 */
+	kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu));
 	return 1;
 }
 
@@ -239,6 +265,7 @@ static exit_handle_fn arm_exit_handlers[] = {
 	[ESR_ELx_EC_SMC32]	= handle_smc,
 	[ESR_ELx_EC_HVC64]	= handle_hvc,
 	[ESR_ELx_EC_SMC64]	= handle_smc,
+	[ESR_ELx_EC_SVC64]	= handle_svc,
 	[ESR_ELx_EC_SYS64]	= kvm_handle_sys_reg,
 	[ESR_ELx_EC_SVE]	= handle_sve,
 	[ESR_ELx_EC_ERET]	= kvm_handle_eret,