[PATCH v5 6/6] KVM: arm64: Refactor writings for PMUVer/CSV2/CSV3
Jing Zhang
jingzhangos at google.com
Sun Apr 2 11:37:35 PDT 2023
Refactor writings for ID_AA64PFR0_EL1.[CSV2|CSV3],
ID_AA64DFR0_EL1.PMUVer and ID_DFR0_ELF.PerfMon based on utilities
introduced by ID register descriptor.
No functional change intended.
Co-developed-by: Reiji Watanabe <reijiw at google.com>
Signed-off-by: Reiji Watanabe <reijiw at google.com>
Signed-off-by: Jing Zhang <jingzhangos at google.com>
---
arch/arm64/include/asm/cpufeature.h | 5 +
arch/arm64/kernel/cpufeature.c | 8 +-
arch/arm64/kvm/id_regs.c | 262 +++++++++++++++++++---------
arch/arm64/kvm/sys_regs.c | 3 +-
arch/arm64/kvm/sys_regs.h | 2 +-
5 files changed, 191 insertions(+), 89 deletions(-)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 6bf013fb110d..f17e74afe3e9 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -915,6 +915,7 @@ static inline unsigned int get_vmid_bits(u64 mmfr1)
return 8;
}
+s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new, s64 cur);
struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id);
extern struct arm64_ftr_override id_aa64mmfr1_override;
@@ -925,6 +926,10 @@ extern struct arm64_ftr_override id_aa64smfr0_override;
extern struct arm64_ftr_override id_aa64isar1_override;
extern struct arm64_ftr_override id_aa64isar2_override;
+extern const struct arm64_ftr_bits ftr_id_dfr0[];
+extern const struct arm64_ftr_bits ftr_id_aa64pfr0[];
+extern const struct arm64_ftr_bits ftr_id_aa64dfr0[];
+
u32 get_kvm_ipa_limit(void);
void dump_cpu_features(void);
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index c331c49a7d19..5b0e3379e5f8 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -225,7 +225,7 @@ static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
ARM64_FTR_END,
};
-static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
+const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_CSV3_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_CSV2_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR0_EL1_DIT_SHIFT, 4, 0),
@@ -426,7 +426,7 @@ static const struct arm64_ftr_bits ftr_id_mmfr0[] = {
ARM64_FTR_END,
};
-static const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
+const struct arm64_ftr_bits ftr_id_aa64dfr0[] = {
S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_DoubleLock_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_PMSVer_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64DFR0_EL1_CTX_CMPs_SHIFT, 4, 0),
@@ -578,7 +578,7 @@ static const struct arm64_ftr_bits ftr_id_pfr2[] = {
ARM64_FTR_END,
};
-static const struct arm64_ftr_bits ftr_id_dfr0[] = {
+const struct arm64_ftr_bits ftr_id_dfr0[] = {
/* [31:28] TraceFilt */
S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_EXACT, ID_DFR0_EL1_PerfMon_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_DFR0_EL1_MProfDbg_SHIFT, 4, 0),
@@ -791,7 +791,7 @@ static u64 arm64_ftr_set_value(const struct arm64_ftr_bits *ftrp, s64 reg,
return reg;
}
-static s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
+s64 arm64_ftr_safe_value(const struct arm64_ftr_bits *ftrp, s64 new,
s64 cur)
{
s64 ret = 0;
diff --git a/arch/arm64/kvm/id_regs.c b/arch/arm64/kvm/id_regs.c
index af86001e2686..395eaf84a0ab 100644
--- a/arch/arm64/kvm/id_regs.c
+++ b/arch/arm64/kvm/id_regs.c
@@ -39,6 +39,64 @@ struct id_reg_desc {
u64 (*read_kvm_sanitised_reg)(const struct id_reg_desc *idr);
};
+static struct id_reg_desc id_reg_descs[];
+
+/**
+ * arm64_check_features() - Check if a feature register value constitutes
+ * a subset of features indicated by @limit.
+ *
+ * @ftrp: Pointer to an array of arm64_ftr_bits. It must be terminated by
+ * an item whose width field is zero.
+ * @writable_mask: Indicates writable feature bits.
+ * @val: The feature register value to check
+ * @limit: The limit value of the feature register
+ *
+ * This function will check if each feature field of @val is the "safe" value
+ * against @limit based on @ftrp[], each of which specifies the target field
+ * (shift, width), whether or not the field is for a signed value (sign),
+ * how the field is determined to be "safe" (type), and the safe value
+ * (safe_val) when type == FTR_EXACT (safe_val won't be used by this
+ * function when type != FTR_EXACT). Any other fields in arm64_ftr_bits
+ * won't be used by this function. If a field value in @val is the same
+ * as the one in @limit, it is always considered the safe value regardless
+ * of the type. For register fields that are not in writable, only the value
+ * in @limit is considered the safe value.
+ *
+ * Return: 0 if all the fields are safe. Otherwise, return negative errno.
+ */
+static int arm64_check_features(const struct arm64_ftr_bits *ftrp,
+ u64 writable_mask, u64 val, u64 limit)
+{
+ u64 mask = 0;
+
+ for (; ftrp && ftrp->width; ftrp++) {
+ s64 f_val, f_lim, safe_val;
+ u64 ftr_mask;
+
+ ftr_mask = arm64_ftr_mask(ftrp);
+ if ((ftr_mask & writable_mask) != ftr_mask)
+ continue;
+
+ f_val = arm64_ftr_value(ftrp, val);
+ f_lim = arm64_ftr_value(ftrp, limit);
+ mask |= ftr_mask;
+
+ if (f_val == f_lim)
+ safe_val = f_val;
+ else
+ safe_val = arm64_ftr_safe_value(ftrp, f_val, f_lim);
+
+ if (safe_val != f_val)
+ return -E2BIG;
+ }
+
+ /* For fields that are not writable, values in limit are the safe values. */
+ if ((val & ~mask) != (limit & ~mask))
+ return -E2BIG;
+
+ return 0;
+}
+
static u8 vcpu_pmuver(const struct kvm_vcpu *vcpu)
{
if (kvm_vcpu_has_pmu(vcpu))
@@ -84,7 +142,6 @@ u64 kvm_arm_read_id_reg(const struct kvm_vcpu *vcpu, u32 id)
case SYS_ID_AA64PFR0_EL1:
if (!vcpu_has_sve(vcpu))
val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_SVE);
- val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AMU);
if (kvm_vgic_global_state.type == VGIC_V3) {
val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_GIC);
val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_GIC), 1);
@@ -111,15 +168,10 @@ u64 kvm_arm_read_id_reg(const struct kvm_vcpu *vcpu, u32 id)
val &= ~ARM64_FEATURE_MASK(ID_AA64ISAR2_EL1_WFxT);
break;
case SYS_ID_AA64DFR0_EL1:
- /* Limit debug to ARMv8.0 */
- val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer);
- val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer), 6);
/* Set PMUver to the required version */
val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer),
vcpu_pmuver(vcpu));
- /* Hide SPE from guests */
- val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMSVer);
break;
case SYS_ID_DFR0_EL1:
val &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
@@ -178,9 +230,16 @@ static int get_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
static int set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd,
u64 val)
{
- /* This is what we mean by invariant: you can't change it. */
- if (val != read_id_reg(vcpu, rd))
- return -EINVAL;
+ int ret;
+ int id = reg_to_encoding(rd);
+ const struct id_reg_desc *idr = &id_reg_descs[IDREG_IDX(id)];
+
+ ret = arm64_check_features(idr->ftr_bits, idr->writable_mask, val,
+ idr->read_kvm_sanitised_reg ? idr->read_kvm_sanitised_reg(idr) : 0);
+ if (ret)
+ return ret;
+
+ IDREG(vcpu->kvm, id) = val;
return 0;
}
@@ -219,12 +278,39 @@ static u64 general_read_kvm_sanitised_reg(const struct id_reg_desc *idr)
return read_sanitised_ftr_reg(reg_to_encoding(&idr->reg_desc));
}
+static u64 read_sanitised_id_aa64pfr0_el1(const struct id_reg_desc *idr)
+{
+ u64 val;
+ u32 id = reg_to_encoding(&idr->reg_desc);
+
+ val = read_sanitised_ftr_reg(id);
+ /*
+ * The default is to expose CSV2 == 1 if the HW isn't affected.
+ * Although this is a per-CPU feature, we make it global because
+ * asymmetric systems are just a nuisance.
+ *
+ * Userspace can override this as long as it doesn't promise
+ * the impossible.
+ */
+ if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) {
+ val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2);
+ val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2), 1);
+ }
+ if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED) {
+ val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3);
+ val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3), 1);
+ }
+
+ val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AMU);
+
+ return val;
+}
+
static int set_id_aa64pfr0_el1(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd,
u64 val)
{
u8 csv2, csv3;
- u64 sval = val;
/*
* Allow AA64PFR0_EL1.CSV2 to be set from userspace as long as
@@ -232,26 +318,37 @@ static int set_id_aa64pfr0_el1(struct kvm_vcpu *vcpu,
* guest could otherwise be covered in ectoplasmic residue).
*/
csv2 = cpuid_feature_extract_unsigned_field(val, ID_AA64PFR0_EL1_CSV2_SHIFT);
- if (csv2 > 1 ||
- (csv2 && arm64_get_spectre_v2_state() != SPECTRE_UNAFFECTED))
+ if (csv2 > 1 || (csv2 && arm64_get_spectre_v2_state() != SPECTRE_UNAFFECTED))
return -EINVAL;
/* Same thing for CSV3 */
csv3 = cpuid_feature_extract_unsigned_field(val, ID_AA64PFR0_EL1_CSV3_SHIFT);
- if (csv3 > 1 ||
- (csv3 && arm64_get_meltdown_state() != SPECTRE_UNAFFECTED))
+ if (csv3 > 1 || (csv3 && arm64_get_meltdown_state() != SPECTRE_UNAFFECTED))
return -EINVAL;
- /* We can only differ with CSV[23], and anything else is an error */
- val ^= read_id_reg(vcpu, rd);
- val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) |
- ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3));
- if (val)
- return -EINVAL;
+ return set_id_reg(vcpu, rd, val);
+}
- IDREG(vcpu->kvm, reg_to_encoding(rd)) = sval;
+static u64 read_sanitised_id_aa64dfr0_el1(const struct id_reg_desc *idr)
+{
+ u64 val;
+ u32 id = reg_to_encoding(&idr->reg_desc);
- return 0;
+ val = read_sanitised_ftr_reg(id);
+ /* Limit debug to ARMv8.0 */
+ val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer);
+ val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer), 6);
+ /*
+ * Initialise the default PMUver before there is a chance to
+ * create an actual PMU.
+ */
+ val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
+ val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer),
+ kvm_arm_pmu_get_pmuver_limit());
+ /* Hide SPE from guests */
+ val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMSVer);
+
+ return val;
}
static int set_id_aa64dfr0_el1(struct kvm_vcpu *vcpu,
@@ -260,6 +357,7 @@ static int set_id_aa64dfr0_el1(struct kvm_vcpu *vcpu,
{
u8 pmuver, host_pmuver;
bool valid_pmu;
+ int ret;
host_pmuver = kvm_arm_pmu_get_pmuver_limit();
@@ -279,23 +377,25 @@ static int set_id_aa64dfr0_el1(struct kvm_vcpu *vcpu,
if (kvm_vcpu_has_pmu(vcpu) != valid_pmu)
return -EINVAL;
- /* We can only differ with PMUver, and anything else is an error */
- val ^= read_id_reg(vcpu, rd);
- val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
- if (val)
- return -EINVAL;
-
if (valid_pmu) {
mutex_lock(&vcpu->kvm->arch.config_lock);
- IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
- IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) |=
- FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), pmuver);
+ ret = set_id_reg(vcpu, rd, val);
+ if (ret) {
+ mutex_unlock(&vcpu->kvm->arch.config_lock);
+ return ret;
+ }
IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) |=
FIELD_PREP(ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon), pmuver_to_perfmon(pmuver));
mutex_unlock(&vcpu->kvm->arch.config_lock);
} else {
+ /* We can only differ with PMUver, and anything else is an error */
+ val ^= read_id_reg(vcpu, rd);
+ val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
+ if (val)
+ return -EINVAL;
+
assign_bit(KVM_ARCH_FLAG_VCPU_HAS_IMP_DEF_PMU, &vcpu->kvm->arch.flags,
pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF);
}
@@ -303,12 +403,29 @@ static int set_id_aa64dfr0_el1(struct kvm_vcpu *vcpu,
return 0;
}
+static u64 read_sanitised_id_dfr0_el1(const struct id_reg_desc *idr)
+{
+ u64 val;
+ u32 id = reg_to_encoding(&idr->reg_desc);
+
+ val = read_sanitised_ftr_reg(id);
+ /*
+ * Initialise the default PMUver before there is a chance to
+ * create an actual PMU.
+ */
+ val &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
+ val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon), kvm_arm_pmu_get_pmuver_limit());
+
+ return val;
+}
+
static int set_id_dfr0_el1(struct kvm_vcpu *vcpu,
const struct sys_reg_desc *rd,
u64 val)
{
u8 perfmon, host_perfmon;
bool valid_pmu;
+ int ret;
host_perfmon = pmuver_to_perfmon(kvm_arm_pmu_get_pmuver_limit());
@@ -329,23 +446,25 @@ static int set_id_dfr0_el1(struct kvm_vcpu *vcpu,
if (kvm_vcpu_has_pmu(vcpu) != valid_pmu)
return -EINVAL;
- /* We can only differ with PerfMon, and anything else is an error */
- val ^= read_id_reg(vcpu, rd);
- val &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
- if (val)
- return -EINVAL;
-
if (valid_pmu) {
mutex_lock(&vcpu->kvm->arch.config_lock);
- IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
- IDREG(vcpu->kvm, SYS_ID_DFR0_EL1) |=
- FIELD_PREP(ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon), perfmon);
+ ret = set_id_reg(vcpu, rd, val);
+ if (ret) {
+ mutex_unlock(&vcpu->kvm->arch.config_lock);
+ return ret;
+ }
IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
IDREG(vcpu->kvm, SYS_ID_AA64DFR0_EL1) |=
FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), perfmon_to_pmuver(perfmon));
mutex_unlock(&vcpu->kvm->arch.config_lock);
} else {
+ /* We can only differ with PerfMon, and anything else is an error */
+ val ^= read_id_reg(vcpu, rd);
+ val &= ~ARM64_FEATURE_MASK(ID_DFR0_EL1_PerfMon);
+ if (val)
+ return -EINVAL;
+
assign_bit(KVM_ARCH_FLAG_VCPU_HAS_IMP_DEF_PMU, &vcpu->kvm->arch.flags,
perfmon == ID_DFR0_EL1_PerfMon_IMPDEF);
}
@@ -354,14 +473,16 @@ static int set_id_dfr0_el1(struct kvm_vcpu *vcpu,
}
/* sys_reg_desc initialiser for known cpufeature ID registers */
+#define SYS_DESC_SANITISED(name) { \
+ SYS_DESC(SYS_##name), \
+ .access = access_id_reg, \
+ .get_user = get_id_reg, \
+ .set_user = set_id_reg, \
+ .visibility = id_visibility, \
+}
+
#define ID_SANITISED(name) { \
- .reg_desc = { \
- SYS_DESC(SYS_##name), \
- .access = access_id_reg, \
- .get_user = get_id_reg, \
- .set_user = set_id_reg, \
- .visibility = id_visibility, \
- }, \
+ .reg_desc = SYS_DESC_SANITISED(name), \
.ftr_bits = NULL, \
.writable_mask = 0, \
.read_kvm_sanitised_reg = general_read_kvm_sanitised_reg, \
@@ -417,7 +538,7 @@ static int set_id_dfr0_el1(struct kvm_vcpu *vcpu,
.read_kvm_sanitised_reg = NULL, \
}
-static const struct id_reg_desc id_reg_descs[KVM_ARM_ID_REG_NUM] = {
+static struct id_reg_desc id_reg_descs[KVM_ARM_ID_REG_NUM] = {
/*
* ID regs: all ID_SANITISED() entries here must have corresponding
* entries in arm64_ftr_regs[].
@@ -433,6 +554,9 @@ static const struct id_reg_desc id_reg_descs[KVM_ARM_ID_REG_NUM] = {
.get_user = get_id_reg,
.set_user = set_id_dfr0_el1,
.visibility = aa32_id_visibility, },
+ .ftr_bits = ftr_id_dfr0,
+ .writable_mask = ID_DFR0_EL1_PerfMon_MASK,
+ .read_kvm_sanitised_reg = read_sanitised_id_dfr0_el1,
},
ID_HIDDEN(ID_AFR0_EL1),
AA32_ID_SANITISED(ID_MMFR0_EL1),
@@ -467,6 +591,9 @@ static const struct id_reg_desc id_reg_descs[KVM_ARM_ID_REG_NUM] = {
.access = access_id_reg,
.get_user = get_id_reg,
.set_user = set_id_aa64pfr0_el1, },
+ .ftr_bits = ftr_id_aa64pfr0,
+ .writable_mask = ID_AA64PFR0_EL1_CSV2_MASK | ID_AA64PFR0_EL1_CSV3_MASK,
+ .read_kvm_sanitised_reg = read_sanitised_id_aa64pfr0_el1,
},
ID_SANITISED(ID_AA64PFR1_EL1),
ID_UNALLOCATED(4, 2),
@@ -482,6 +609,9 @@ static const struct id_reg_desc id_reg_descs[KVM_ARM_ID_REG_NUM] = {
.access = access_id_reg,
.get_user = get_id_reg,
.set_user = set_id_aa64dfr0_el1, },
+ .ftr_bits = ftr_id_aa64dfr0,
+ .writable_mask = ID_AA64DFR0_EL1_PMUVer_MASK,
+ .read_kvm_sanitised_reg = read_sanitised_id_aa64dfr0_el1,
},
ID_SANITISED(ID_AA64DFR1_EL1),
ID_UNALLOCATED(5, 2),
@@ -607,7 +737,7 @@ int kvm_arm_set_id_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return ret;
}
-bool kvm_arm_check_idreg_table(void)
+bool kvm_arm_idreg_table_init(void)
{
unsigned int i;
@@ -641,10 +771,7 @@ int kvm_arm_walk_id_regs(struct kvm_vcpu *vcpu, u64 __user *uind)
return total;
}
-/*
- * Set the guest's ID registers that are defined in id_reg_descs[]
- * with ID_SANITISED() to the host's sanitized value.
- */
+/* Initialize the guest's ID registers with KVM sanitised values. */
void kvm_arm_init_id_regs(struct kvm *kvm)
{
int i;
@@ -660,33 +787,4 @@ void kvm_arm_init_id_regs(struct kvm *kvm)
IDREG(kvm, id) = val;
}
-
- /*
- * The default is to expose CSV2 == 1 if the HW isn't affected.
- * Although this is a per-CPU feature, we make it global because
- * asymmetric systems are just a nuisance.
- *
- * Userspace can override this as long as it doesn't promise
- * the impossible.
- */
- val = IDREG(kvm, SYS_ID_AA64PFR0_EL1);
-
- if (arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) {
- val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2);
- val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2), 1);
- }
- if (arm64_get_meltdown_state() == SPECTRE_UNAFFECTED) {
- val &= ~ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3);
- val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3), 1);
- }
-
- IDREG(kvm, SYS_ID_AA64PFR0_EL1) = val;
-
- /*
- * Initialise the default PMUver before there is a chance to
- * create an actual PMU.
- */
- IDREG(kvm, SYS_ID_AA64DFR0_EL1) &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer);
- IDREG(kvm, SYS_ID_AA64DFR0_EL1) |=
- FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), kvm_arm_pmu_get_pmuver_limit());
}
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 1d7fb0acf154..27cff8022754 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -2940,14 +2940,13 @@ int __init kvm_sys_reg_table_init(void)
unsigned int i;
/* Make sure tables are unique and in order. */
- valid &= kvm_arm_check_idreg_table();
valid &= check_sysreg_table(sys_reg_descs, ARRAY_SIZE(sys_reg_descs), false);
valid &= check_sysreg_table(cp14_regs, ARRAY_SIZE(cp14_regs), true);
valid &= check_sysreg_table(cp14_64_regs, ARRAY_SIZE(cp14_64_regs), true);
valid &= check_sysreg_table(cp15_regs, ARRAY_SIZE(cp15_regs), true);
valid &= check_sysreg_table(cp15_64_regs, ARRAY_SIZE(cp15_64_regs), true);
valid &= check_sysreg_table(invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs), false);
-
+ valid &= kvm_arm_idreg_table_init();
if (!valid)
return -EINVAL;
diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h
index 15a0a1e2fe99..df8d26df93ec 100644
--- a/arch/arm64/kvm/sys_regs.h
+++ b/arch/arm64/kvm/sys_regs.h
@@ -246,7 +246,7 @@ int walk_one_sys_reg(const struct kvm_vcpu *vcpu,
int emulate_id_reg(struct kvm_vcpu *vcpu, struct sys_reg_params *params);
int kvm_arm_get_id_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
int kvm_arm_set_id_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
-bool kvm_arm_check_idreg_table(void);
+bool kvm_arm_idreg_table_init(void);
int kvm_arm_walk_id_regs(struct kvm_vcpu *vcpu, u64 __user *uind);
u64 kvm_arm_read_id_reg(const struct kvm_vcpu *vcpu, u32 id);
--
2.40.0.348.gf938b09366-goog
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