[PATCH v2 22/28] KVM: arm64: Add routing for NVHCR_EL2 trap

[Marc Zyngier]

NVHCR_EL2 accesses from EL1 are taken to EL2 when HCRX_EL2.NVTGE==0
and HCR_EL2.NV==1. Describe this in the exception routing tables.

Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/kvm/emulate-nested.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm64/kvm/emulate-nested.c b/arch/arm64/kvm/emulate-nested.c
index b7f3d86a94031..625604019fb32 100644
--- a/arch/arm64/kvm/emulate-nested.c
+++ b/arch/arm64/kvm/emulate-nested.c
@@ -136,6 +136,8 @@ enum cgt_group_id {
 	CGT_CPTR_TTA,
 	CGT_MDCR_HPMN,
 
+	CGT_HCR_NV_HCRX_nNVTGE,
+
 	/* Must be last */
 	__NR_CGT_GROUP_IDS__
 };
@@ -588,6 +590,15 @@ static enum trap_behaviour check_mdcr_hpmn(struct kvm_vcpu *vcpu)
 	return BEHAVE_HANDLE_LOCALLY;
 }
 
+static enum trap_behaviour check_hcr_nv_hcrx_nnvtge(struct kvm_vcpu *vcpu)
+{
+	if ((__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_EL2_NV) &&
+	    !(__vcpu_sys_reg(vcpu, HCRX_EL2) & HCRX_EL2_NVTGE))
+		return BEHAVE_FORWARD_RW;
+
+	return BEHAVE_HANDLE_LOCALLY;
+}
+
 #define CCC(id, fn)				\
 	[id - __COMPLEX_CONDITIONS__] = fn
 
@@ -598,6 +609,7 @@ static const complex_condition_check ccc[] = {
 	CCC(CGT_CNTHCTL_EL1NVVCT, check_cnthctl_el1nvvct),
 	CCC(CGT_CPTR_TTA, check_cptr_tta),
 	CCC(CGT_MDCR_HPMN, check_mdcr_hpmn),
+	CCC(CGT_HCR_NV_HCRX_nNVTGE, check_hcr_nv_hcrx_nnvtge),
 };
 
 /*
@@ -853,6 +865,7 @@ static const struct encoding_to_trap_config encoding_to_cgt[] __initconst = {
 	SR_TRAP(SYS_SCTLR2_EL2,		CGT_HCR_NV),
 	SR_RANGE_TRAP(SYS_HCR_EL2,
 		      SYS_HCRX_EL2,	CGT_HCR_NV),
+	SR_TRAP(SYS_NVHCR_EL2,		CGT_HCR_NV_HCRX_nNVTGE),
 	SR_TRAP(SYS_SMPRIMAP_EL2,	CGT_HCR_NV),
 	SR_TRAP(SYS_SMCR_EL2,		CGT_HCR_NV),
 	SR_RANGE_TRAP(SYS_TTBR0_EL2,
-- 
2.47.3