[PATCH v1 5/6] KVM: arm64: Trap external trace for protected VMs

[Fuad Tabba <tabba@google.com>]

pKVM does not support external trace for protected VMs.

Signed-off-by: Fuad Tabba <tabba@google.com>
---
 arch/arm64/kvm/hyp/nvhe/pkvm.c | 4 ++++
 arch/arm64/tools/sysreg        | 5 ++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c
index 9d23a51d7f75..84b5c3f387d8 100644
--- a/arch/arm64/kvm/hyp/nvhe/pkvm.c
+++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c
@@ -136,6 +136,10 @@ static void pvm_init_traps_aa64dfr0(struct kvm_vcpu *vcpu)
 			cptr_set |= CPTR_EL2_TTA;
 	}
 
+	/* Trap External Trace */
+	if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_ExtTrcBuff), feature_ids))
+		mdcr_clear |= MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT;
+
 	vcpu->arch.mdcr_el2 |= mdcr_set;
 	vcpu->arch.mdcr_el2 &= ~mdcr_clear;
 	vcpu->arch.cptr_el2 |= cptr_set;
diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg
index 96cbeeab4eec..02e1a4290fa5 100644
--- a/arch/arm64/tools/sysreg
+++ b/arch/arm64/tools/sysreg
@@ -1115,7 +1115,10 @@ Enum	63:60	HPMN0
 	0b0000	UNPREDICTABLE
 	0b0001	DEF
 EndEnum
-Res0	59:56
+UnsignedEnum	59:56	ExtTrcBuff
+	0b0000	NI
+	0b0001	IMP
+EndEnum
 UnsignedEnum	55:52	BRBE
 	0b0000	NI
 	0b0001	IMP
-- 
2.43.0.rc2.451.g8631bc7472-goog