[PATCH v3 25/66] KVM: arm64: nv: Respect virtual HCR_EL2.TVM and TRVM settings

Marc Zyngier
2020-12-10T16:22:39Z

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

Forward the EL1 virtual memory register traps to the virtual EL2 if they
are not coming from the virtual EL2 and the virtual HCR_EL2.TVM or TRVM
bit is set.

This is for recursive nested virtualization.

Signed-off-by: Jintack Lim <jintack.lim@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/sys_regs.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 8b0be7f0f44d..d09fda0fd76f 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -393,6 +393,13 @@ static bool access_vm_reg(struct kvm_vcpu *vcpu,
if (el12_reg(p) && forward_nv_traps(vcpu))
return false;

+ if (!el12_reg(p)) {
+ u64 bit = p->is_write ? HCR_TVM : HCR_TRVM;
+
+ if (forward_traps(vcpu, bit))
+ return false;
+ }
+
/* We don't expect TRVM on the host */
BUG_ON(!vcpu_mode_el2(vcpu) && !p->is_write);

--
2.29.2