KVM: arm64: Convert VTCR_EL2 to config-driven sanitisation

Describe all the VTCR_EL2 fields and their respective configurations,
making sure that we correctly ignore the bits that are not defined
for a given guest configuration.

Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20251210173024.561160-6-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/kvm/config.c b/arch/arm64/kvm/config.c
index 3845b188551b60bbc052ace58cde1eadc827ee3c..9c04f895d376947a20d0ca91b3d7e1953c9e3469 100644 (file)
--- a/arch/arm64/kvm/config.c
+++ b/arch/arm64/kvm/config.c
@@ -141,6 +141,7 @@ struct reg_feat_map_desc {
 #define FEAT_AA64EL1           ID_AA64PFR0_EL1, EL1, IMP
 #define FEAT_AA64EL2           ID_AA64PFR0_EL1, EL2, IMP
 #define FEAT_AA64EL3           ID_AA64PFR0_EL1, EL3, IMP
+#define FEAT_SEL2              ID_AA64PFR0_EL1, SEL2, IMP
 #define FEAT_AIE               ID_AA64MMFR3_EL1, AIE, IMP
 #define FEAT_S2POE             ID_AA64MMFR3_EL1, S2POE, IMP
 #define FEAT_S1POE             ID_AA64MMFR3_EL1, S1POE, IMP
@@ -202,6 +203,8 @@ struct reg_feat_map_desc {
 #define FEAT_ASID2             ID_AA64MMFR4_EL1, ASID2, IMP
 #define FEAT_MEC               ID_AA64MMFR3_EL1, MEC, IMP
 #define FEAT_HAFT              ID_AA64MMFR1_EL1, HAFDBS, HAFT
+#define FEAT_HDBSS             ID_AA64MMFR1_EL1, HAFDBS, HDBSS
+#define FEAT_HPDS2             ID_AA64MMFR1_EL1, HPDS, HPDS2
 #define FEAT_BTI               ID_AA64PFR1_EL1, BT, IMP
 #define FEAT_ExS               ID_AA64MMFR0_EL1, EXS, IMP
 #define FEAT_IESB              ID_AA64MMFR2_EL1, IESB, IMP
@@ -219,6 +222,7 @@ struct reg_feat_map_desc {
 #define FEAT_FGT2              ID_AA64MMFR0_EL1, FGT, FGT2
 #define FEAT_MTPMU             ID_AA64DFR0_EL1, MTPMU, IMP
 #define FEAT_HCX               ID_AA64MMFR1_EL1, HCX, IMP
+#define FEAT_S2PIE             ID_AA64MMFR3_EL1, S2PIE, IMP
 
 static bool not_feat_aa64el3(struct kvm *kvm)
 {
@@ -362,6 +366,28 @@ static bool feat_pmuv3p9(struct kvm *kvm)
        return check_pmu_revision(kvm, V3P9);
 }
 
+#define has_feat_s2tgran(k, s)                                         \
+  ((kvm_has_feat_enum(kvm, ID_AA64MMFR0_EL1, TGRAN##s##_2, TGRAN##s) && \
+    kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN##s, IMP))                     || \
+   kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN##s##_2, IMP))
+
+static bool feat_lpa2(struct kvm *kvm)
+{
+       return ((kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN4, 52_BIT)    ||
+                !kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN4, IMP))     &&
+               (kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN16, 52_BIT)   ||
+                !kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN16, IMP))    &&
+               (kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN4_2, 52_BIT)  ||
+                !has_feat_s2tgran(kvm, 4))                             &&
+               (kvm_has_feat(kvm, ID_AA64MMFR0_EL1, TGRAN16_2, 52_BIT) ||
+                !has_feat_s2tgran(kvm, 16)));
+}
+
+static bool feat_vmid16(struct kvm *kvm)
+{
+       return kvm_has_feat_enum(kvm, ID_AA64MMFR1_EL1, VMIDBits, 16);
+}
+
 static bool compute_hcr_rw(struct kvm *kvm, u64 *bits)
 {
        /* This is purely academic: AArch32 and NV are mutually exclusive */
@@ -1168,6 +1194,44 @@ static const struct reg_bits_to_feat_map mdcr_el2_feat_map[] = {
 static const DECLARE_FEAT_MAP(mdcr_el2_desc, MDCR_EL2,
                              mdcr_el2_feat_map, FEAT_AA64EL2);
 
+static const struct reg_bits_to_feat_map vtcr_el2_feat_map[] = {
+       NEEDS_FEAT(VTCR_EL2_HDBSS, FEAT_HDBSS),
+       NEEDS_FEAT(VTCR_EL2_HAFT, FEAT_HAFT),
+       NEEDS_FEAT(VTCR_EL2_TL0         |
+                  VTCR_EL2_TL1         |
+                  VTCR_EL2_AssuredOnly |
+                  VTCR_EL2_GCSH,
+                  FEAT_THE),
+       NEEDS_FEAT(VTCR_EL2_D128, FEAT_D128),
+       NEEDS_FEAT(VTCR_EL2_S2POE, FEAT_S2POE),
+       NEEDS_FEAT(VTCR_EL2_S2PIE, FEAT_S2PIE),
+       NEEDS_FEAT(VTCR_EL2_SL2         |
+                  VTCR_EL2_DS,
+                  feat_lpa2),
+       NEEDS_FEAT(VTCR_EL2_NSA         |
+                  VTCR_EL2_NSW,
+                  FEAT_SEL2),
+       NEEDS_FEAT(VTCR_EL2_HWU62       |
+                  VTCR_EL2_HWU61       |
+                  VTCR_EL2_HWU60       |
+                  VTCR_EL2_HWU59,
+                  FEAT_HPDS2),
+       NEEDS_FEAT(VTCR_EL2_HD, ID_AA64MMFR1_EL1, HAFDBS, DBM),
+       NEEDS_FEAT(VTCR_EL2_HA, ID_AA64MMFR1_EL1, HAFDBS, AF),
+       NEEDS_FEAT(VTCR_EL2_VS, feat_vmid16),
+       NEEDS_FEAT(VTCR_EL2_PS          |
+                  VTCR_EL2_TG0         |
+                  VTCR_EL2_SH0         |
+                  VTCR_EL2_ORGN0       |
+                  VTCR_EL2_IRGN0       |
+                  VTCR_EL2_SL0         |
+                  VTCR_EL2_T0SZ,
+                  FEAT_AA64EL1),
+};
+
+static const DECLARE_FEAT_MAP(vtcr_el2_desc, VTCR_EL2,
+                             vtcr_el2_feat_map, FEAT_AA64EL2);
+
 static void __init check_feat_map(const struct reg_bits_to_feat_map *map,
                                  int map_size, u64 resx, const char *str)
 {
@@ -1211,6 +1275,7 @@ void __init check_feature_map(void)
        check_reg_desc(&tcr2_el2_desc);
        check_reg_desc(&sctlr_el1_desc);
        check_reg_desc(&mdcr_el2_desc);
+       check_reg_desc(&vtcr_el2_desc);
 }
 
 static bool idreg_feat_match(struct kvm *kvm, const struct reg_bits_to_feat_map *map)
@@ -1425,6 +1490,10 @@ void get_reg_fixed_bits(struct kvm *kvm, enum vcpu_sysreg reg, u64 *res0, u64 *r
                *res0 = compute_reg_res0_bits(kvm, &mdcr_el2_desc, 0, 0);
                *res1 = MDCR_EL2_RES1;
                break;
+       case VTCR_EL2:
+               *res0 = compute_reg_res0_bits(kvm, &vtcr_el2_desc, 0, 0);
+               *res1 = VTCR_EL2_RES1;
+               break;
        default:
                WARN_ON_ONCE(1);
                *res0 = *res1 = 0;

diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
index 522fa3cc95783094acb674158266938c04a0b223..486eba72bb027b1f8a657102061747179f52bd67 100644 (file)
--- a/arch/arm64/kvm/nested.c
+++ b/arch/arm64/kvm/nested.c
@@ -1719,8 +1719,7 @@ int kvm_init_nv_sysregs(struct kvm_vcpu *vcpu)
        set_sysreg_masks(kvm, VTTBR_EL2, res0, res1);
 
        /* VTCR_EL2 */
-       res0 = GENMASK(63, 32) | GENMASK(30, 20);
-       res1 = BIT(31);
+       get_reg_fixed_bits(kvm, VTCR_EL2, &res0, &res1);
        set_sysreg_masks(kvm, VTCR_EL2, res0, res1);
 
        /* VMPIDR_EL2 */