From: Jintack Lim <jintack.lim@xxxxxxxxxx>
This introduces a function prototype to determine if we need to forward
system instruction traps to the virtual EL2. The implementation of
forward_trap functions for each system instruction will be added in
later patches.
Signed-off-by: Jintack Lim <jintack.lim@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/kvm/sys_regs.c | 8 ++++++++
arch/arm64/kvm/sys_regs.h | 6 ++++++
2 files changed, 14 insertions(+)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 3922ecc00869..77f07f960d84 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -2598,6 +2598,14 @@ static void perform_access(struct kvm_vcpu *vcpu,
*/
BUG_ON(!r->access);
+ /*
+ * Forward this trap to the virtual EL2 if the guest hypervisor has
+ * configured to trap the current instruction.
+ */
+ if (nested_virt_in_use(vcpu) && r->forward_trap
+ && unlikely(r->forward_trap(vcpu)))
+ return;
+
/* Skip instruction if instructed so */
if (likely(r->access(vcpu, params, r)))
kvm_incr_pc(vcpu);
diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h
index d260c26b1834..267b2f37444c 100644
--- a/arch/arm64/kvm/sys_regs.h
+++ b/arch/arm64/kvm/sys_regs.h
@@ -72,6 +72,12 @@ struct sys_reg_desc {
int (*set_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
const struct kvm_one_reg *reg, void __user *uaddr);
+ /*
+ * Forward the trap to the virtual EL2 if the guest hypervisor has
+ * configured to trap the current instruction.
+ */
+ bool (*forward_trap)(struct kvm_vcpu *vcpu);
+
/* Return mask of REG_* runtime visibility overrides */
unsigned int (*visibility)(const struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd);
--
2.30.2
