[PATCH v4 10/66] KVM: arm64: nv: Inject HVC exceptions to the virtual EL2

[Marc Zyngier]

From: Jintack Lim <jintack.lim at linaro.org>

As we expect all PSCI calls from the L1 hypervisor to be performed
using SMC when nested virtualization is enabled, it is clear that
all HVC instruction from the VM (including from the virtual EL2)
are supposed to handled in the virtual EL2.

Forward these to EL2 as required.

Signed-off-by: Jintack Lim <jintack.lim at linaro.org>
[maz: add handling of HCR_EL2.HCD]
Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/kvm/handle_exit.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 6f48336b1d86..6add422d63b8 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -16,6 +16,7 @@
 #include <asm/kvm_asm.h>
 #include <asm/kvm_emulate.h>
 #include <asm/kvm_mmu.h>
+#include <asm/kvm_nested.h>
 #include <asm/debug-monitors.h>
 #include <asm/traps.h>
 
@@ -40,6 +41,16 @@ static int handle_hvc(struct kvm_vcpu *vcpu)
 			    kvm_vcpu_hvc_get_imm(vcpu));
 	vcpu->stat.hvc_exit_stat++;
 
+	/* Forward hvc instructions to the virtual EL2 if the guest has EL2. */
+	if (nested_virt_in_use(vcpu)) {
+		if (vcpu_read_sys_reg(vcpu, HCR_EL2) & HCR_HCD)
+			kvm_inject_undefined(vcpu);
+		else
+			kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu));
+
+		return 1;
+	}
+
 	ret = kvm_hvc_call_handler(vcpu);
 	if (ret < 0) {
 		vcpu_set_reg(vcpu, 0, ~0UL);
-- 
2.29.2