[PATCH v5 12/37] KVM: arm64: Sanitise TCR2_EL2

Marc Zyngier
2024-10-23T14:53:54Z

TCR2_EL2 is a bag of control bits, all of which are only valid if
certain features are present, and RES0 otherwise.

Describe these constraints and register them with the masking
infrastructure.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/nested.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
index b20b3bfb9caec..b4b3ec88399b3 100644
--- a/arch/arm64/kvm/nested.c
+++ b/arch/arm64/kvm/nested.c
@@ -1179,6 +1179,28 @@ int kvm_init_nv_sysregs(struct kvm *kvm)
res0 |= ~(res0 | res1);
set_sysreg_masks(kvm, HAFGRTR_EL2, res0, res1);

+ /* TCR2_EL2 */
+ res0 = TCR2_EL2_RES0;
+ res1 = TCR2_EL2_RES1;
+ if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, D128, IMP))
+ res0 |= (TCR2_EL2_DisCH0 | TCR2_EL2_DisCH1 | TCR2_EL2_D128);
+ if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, MEC, IMP))
+ res0 |= TCR2_EL2_AMEC1 | TCR2_EL2_AMEC0;
+ if (!kvm_has_feat(kvm, ID_AA64MMFR1_EL1, HAFDBS, HAFT))
+ res0 |= TCR2_EL2_HAFT;
+ if (!kvm_has_feat(kvm, ID_AA64PFR1_EL1, THE, IMP))
+ res0 |= TCR2_EL2_PTTWI | TCR2_EL2_PnCH;
+ if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, AIE, IMP))
+ res0 |= TCR2_EL2_AIE;
+ if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, S1POE, IMP))
+ res0 |= TCR2_EL2_POE | TCR2_EL2_E0POE;
+ if (!kvm_has_feat(kvm, ID_AA64MMFR3_EL1, S1PIE, IMP))
+ res0 |= TCR2_EL2_PIE;
+ if (!kvm_has_feat(kvm, ID_AA64MMFR1_EL1, VH, IMP))
+ res0 |= (TCR2_EL2_E0POE | TCR2_EL2_D128 |
+ TCR2_EL2_AMEC1 | TCR2_EL2_DisCH0 | TCR2_EL2_DisCH1);
+ set_sysreg_masks(kvm, TCR2_EL2, res0, res1);
+
/* SCTLR_EL1 */
res0 = SCTLR_EL1_RES0;
res1 = SCTLR_EL1_RES1;
--
2.39.2