[RFC PATCH v2 38/38] KVM: arm64: Respect the virtual CPTR_EL2.TCPAC setting

Jintack Lim
2017-07-18T16:59:04Z

Forward CPACR_EL1 traps to the virtual EL2 if virtual CPTR_EL2 is
configured to trap CPACR_EL1 accesses from EL1.

This is for recursive nested virtualization.

Signed-off-by: Jintack Lim <jintack.lim@linaro.org>
---
arch/arm64/kvm/sys_regs.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 6f67666..ba2966d 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1091,6 +1091,11 @@ static bool access_cpacr(struct kvm_vcpu *vcpu,
if (el12_reg(p) && forward_nv_traps(vcpu))
return kvm_inject_nested_sync(vcpu, kvm_vcpu_get_hsr(vcpu));

+ /* Forward this trap to the virtual EL2 if CPTR_EL2.TCPAC is set*/
+ if (!el12_reg(p) && !vcpu_mode_el2(vcpu) &&
+ (vcpu_sys_reg(vcpu, CPTR_EL2) & CPTR_EL2_TCPAC))
+ return kvm_inject_nested_sync(vcpu, kvm_vcpu_get_hsr(vcpu));
+
/*
* When the virtual HCR_EL2.E2H == 1, an access to CPACR_EL1
* in the virtual EL2 is to access CPTR_EL2.
--
1.9.1