[PATCH v3 05/17] KVM: arm64: Explicitly trap unsupported HFGxTR_EL2 features

[Fuad Tabba]

Do not rely on the value of __HFGRTR_EL2_nMASK to trap
unsupported features, since the nMASK can (and will) change as
new traps are added and as its value is updated. Instead,
explicitly specify the trap bits.

Suggested-by: Joey Gouly <joey.gouly at arm.com>
Signed-off-by: Fuad Tabba <tabba at google.com>
---
 arch/arm64/kvm/hyp/include/hyp/switch.h | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index f99d8af0b9af..7b4909dfd1f5 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -110,12 +110,15 @@ static inline void __activate_traps_hfgxtr(struct kvm_vcpu *vcpu)
 		compute_clr_set(vcpu, HFGWTR_EL2, w_clr, w_set);
 	}
 
-	/* The default is not to trap anything but ACCDATA_EL1 */
-	r_val = __HFGRTR_EL2_nMASK & ~HFGxTR_EL2_nACCDATA_EL1;
+	/* The default to trap everything not handled or supported in KVM. */
+	tmp = HFGxTR_EL2_nAMAIR2_EL1 | HFGxTR_EL2_nMAIR2_EL1 | HFGxTR_EL2_nS2POR_EL1 |
+	      HFGxTR_EL2_nPOR_EL1 | HFGxTR_EL2_nPOR_EL0 | HFGxTR_EL2_nACCDATA_EL1;
+
+	r_val = __HFGRTR_EL2_nMASK & ~tmp;
 	r_val |= r_set;
 	r_val &= ~r_clr;
 
-	w_val = __HFGWTR_EL2_nMASK & ~HFGxTR_EL2_nACCDATA_EL1;
+	w_val = __HFGWTR_EL2_nMASK & ~tmp;
 	w_val |= w_set;
 	w_val &= ~w_clr;
 
-- 
2.43.0.472.g3155946c3a-goog