[PATCH v2 11/15] arm64: KVM/debug: trap all accesses to SPE controls at EL1

From: Sudeep Holla
Date: Thu May 23 2019 - 06:39:03 EST


Now that we have all the save/restore mechanism in place, lets enable
trapping of accesses to SPE profiling buffer controls at EL1 to EL2.
This will also change the translation regime used by buffer from EL2
stage 1 to EL1 stage 1 on VHE systems.

Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
---
arch/arm64/kvm/hyp/switch.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 844f0dd7a7f0..881901825a85 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -110,6 +110,7 @@ static void activate_traps_vhe(struct kvm_vcpu *vcpu)

write_sysreg(val, cpacr_el1);

+ write_sysreg(vcpu->arch.mdcr_el2 | 2 << MDCR_EL2_E2PB_SHIFT, mdcr_el2);
write_sysreg(kvm_get_hyp_vector(), vbar_el1);
}
NOKPROBE_SYMBOL(activate_traps_vhe);
@@ -127,6 +128,7 @@ static void __hyp_text __activate_traps_nvhe(struct kvm_vcpu *vcpu)
__activate_traps_fpsimd32(vcpu);
}

+ write_sysreg(vcpu->arch.mdcr_el2 | 2 << MDCR_EL2_E2PB_SHIFT, mdcr_el2);
write_sysreg(val, cptr_el2);
}

--
2.17.1