Common hypercall firmware register handing is currently employed by psci.c. Since the upcoming patches add more of these registers, it's better to move the generic handling to hypercall.c for a cleaner presentation. While we are at it, collect all the firmware registers under fw_reg_ids[] to help implement kvm_arm_get_fw_num_regs() and kvm_arm_copy_fw_reg_indices() in a generic way. No functional change intended. Signed-off-by: Raghavendra Rao Ananta <rananta@xxxxxxxxxx> --- arch/arm64/kvm/guest.c | 2 +- arch/arm64/kvm/hypercalls.c | 170 +++++++++++++++++++++++++++++++++++ arch/arm64/kvm/psci.c | 166 ---------------------------------- include/kvm/arm_hypercalls.h | 7 ++ include/kvm/arm_psci.h | 7 -- 5 files changed, 178 insertions(+), 174 deletions(-) diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index e116c7767730..8238e52d890d 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -18,7 +18,7 @@ #include <linux/string.h> #include <linux/vmalloc.h> #include <linux/fs.h> -#include <kvm/arm_psci.h> +#include <kvm/arm_hypercalls.h> #include <asm/cputype.h> #include <linux/uaccess.h> #include <asm/fpsimd.h> diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 30da78f72b3b..3c2fcf31ad3d 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -146,3 +146,173 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) smccc_set_retval(vcpu, val[0], val[1], val[2], val[3]); return 1; } + +static const u64 kvm_arm_fw_reg_ids[] = { + KVM_REG_ARM_PSCI_VERSION, + KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1, + KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2, +}; + +int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu) +{ + return ARRAY_SIZE(kvm_arm_fw_reg_ids); +} + +int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(kvm_arm_fw_reg_ids); i++) { + if (put_user(kvm_arm_fw_reg_ids[i], uindices++)) + return -EFAULT; + } + + return 0; +} + +#define KVM_REG_FEATURE_LEVEL_WIDTH 4 +#define KVM_REG_FEATURE_LEVEL_MASK (BIT(KVM_REG_FEATURE_LEVEL_WIDTH) - 1) + +/* + * Convert the workaround level into an easy-to-compare number, where higher + * values mean better protection. + */ +static int get_kernel_wa_level(u64 regid) +{ + switch (regid) { + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: + switch (arm64_get_spectre_v2_state()) { + case SPECTRE_VULNERABLE: + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; + case SPECTRE_MITIGATED: + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL; + case SPECTRE_UNAFFECTED: + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_REQUIRED; + } + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: + switch (arm64_get_spectre_v4_state()) { + case SPECTRE_MITIGATED: + /* + * As for the hypercall discovery, we pretend we + * don't have any FW mitigation if SSBS is there at + * all times. + */ + if (cpus_have_final_cap(ARM64_SSBS)) + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; + fallthrough; + case SPECTRE_UNAFFECTED: + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED; + case SPECTRE_VULNERABLE: + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; + } + } + + return -EINVAL; +} + +int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + void __user *uaddr = (void __user *)(long)reg->addr; + u64 val; + + switch (reg->id) { + case KVM_REG_ARM_PSCI_VERSION: + val = kvm_psci_version(vcpu, vcpu->kvm); + break; + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: + val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK; + break; + default: + return -ENOENT; + } + + if (copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) +{ + void __user *uaddr = (void __user *)(long)reg->addr; + u64 val; + int wa_level; + + if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + switch (reg->id) { + case KVM_REG_ARM_PSCI_VERSION: + { + bool wants_02; + + wants_02 = test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features); + + switch (val) { + case KVM_ARM_PSCI_0_1: + if (wants_02) + return -EINVAL; + vcpu->kvm->arch.psci_version = val; + return 0; + case KVM_ARM_PSCI_0_2: + case KVM_ARM_PSCI_1_0: + if (!wants_02) + return -EINVAL; + vcpu->kvm->arch.psci_version = val; + return 0; + } + break; + } + + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: + if (val & ~KVM_REG_FEATURE_LEVEL_MASK) + return -EINVAL; + + if (get_kernel_wa_level(reg->id) < val) + return -EINVAL; + + return 0; + + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: + if (val & ~(KVM_REG_FEATURE_LEVEL_MASK | + KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED)) + return -EINVAL; + + /* The enabled bit must not be set unless the level is AVAIL. */ + if ((val & KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED) && + (val & KVM_REG_FEATURE_LEVEL_MASK) != KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL) + return -EINVAL; + + /* + * Map all the possible incoming states to the only two we + * really want to deal with. + */ + switch (val & KVM_REG_FEATURE_LEVEL_MASK) { + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL: + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNKNOWN: + wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; + break; + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL: + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED: + wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED; + break; + default: + return -EINVAL; + } + + /* + * We can deal with NOT_AVAIL on NOT_REQUIRED, but not the + * other way around. + */ + if (get_kernel_wa_level(reg->id) < wa_level) + return -EINVAL; + + return 0; + default: + return -ENOENT; + } + + return -EINVAL; +} diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index 3eae32876897..d5bc663a8629 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -403,169 +403,3 @@ int kvm_psci_call(struct kvm_vcpu *vcpu) return -EINVAL; }; } - -int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu) -{ - return 3; /* PSCI version and two workaround registers */ -} - -int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices) -{ - if (put_user(KVM_REG_ARM_PSCI_VERSION, uindices++)) - return -EFAULT; - - if (put_user(KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1, uindices++)) - return -EFAULT; - - if (put_user(KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2, uindices++)) - return -EFAULT; - - return 0; -} - -#define KVM_REG_FEATURE_LEVEL_WIDTH 4 -#define KVM_REG_FEATURE_LEVEL_MASK (BIT(KVM_REG_FEATURE_LEVEL_WIDTH) - 1) - -/* - * Convert the workaround level into an easy-to-compare number, where higher - * values mean better protection. - */ -static int get_kernel_wa_level(u64 regid) -{ - switch (regid) { - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - switch (arm64_get_spectre_v2_state()) { - case SPECTRE_VULNERABLE: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; - case SPECTRE_MITIGATED: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL; - case SPECTRE_UNAFFECTED: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_REQUIRED; - } - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: - switch (arm64_get_spectre_v4_state()) { - case SPECTRE_MITIGATED: - /* - * As for the hypercall discovery, we pretend we - * don't have any FW mitigation if SSBS is there at - * all times. - */ - if (cpus_have_final_cap(ARM64_SSBS)) - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; - fallthrough; - case SPECTRE_UNAFFECTED: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED; - case SPECTRE_VULNERABLE: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; - } - } - - return -EINVAL; -} - -int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) -{ - void __user *uaddr = (void __user *)(long)reg->addr; - u64 val; - - switch (reg->id) { - case KVM_REG_ARM_PSCI_VERSION: - val = kvm_psci_version(vcpu, vcpu->kvm); - break; - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: - val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK; - break; - default: - return -ENOENT; - } - - if (copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id))) - return -EFAULT; - - return 0; -} - -int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) -{ - void __user *uaddr = (void __user *)(long)reg->addr; - u64 val; - int wa_level; - - if (copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id))) - return -EFAULT; - - switch (reg->id) { - case KVM_REG_ARM_PSCI_VERSION: - { - bool wants_02; - - wants_02 = test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features); - - switch (val) { - case KVM_ARM_PSCI_0_1: - if (wants_02) - return -EINVAL; - vcpu->kvm->arch.psci_version = val; - return 0; - case KVM_ARM_PSCI_0_2: - case KVM_ARM_PSCI_1_0: - if (!wants_02) - return -EINVAL; - vcpu->kvm->arch.psci_version = val; - return 0; - } - break; - } - - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - if (val & ~KVM_REG_FEATURE_LEVEL_MASK) - return -EINVAL; - - if (get_kernel_wa_level(reg->id) < val) - return -EINVAL; - - return 0; - - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: - if (val & ~(KVM_REG_FEATURE_LEVEL_MASK | - KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED)) - return -EINVAL; - - /* The enabled bit must not be set unless the level is AVAIL. */ - if ((val & KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED) && - (val & KVM_REG_FEATURE_LEVEL_MASK) != KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL) - return -EINVAL; - - /* - * Map all the possible incoming states to the only two we - * really want to deal with. - */ - switch (val & KVM_REG_FEATURE_LEVEL_MASK) { - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL: - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNKNOWN: - wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; - break; - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL: - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED: - wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED; - break; - default: - return -EINVAL; - } - - /* - * We can deal with NOT_AVAIL on NOT_REQUIRED, but not the - * other way around. - */ - if (get_kernel_wa_level(reg->id) < wa_level) - return -EINVAL; - - return 0; - default: - return -ENOENT; - } - - return -EINVAL; -} diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h index 0e2509d27910..5d38628a8d04 100644 --- a/include/kvm/arm_hypercalls.h +++ b/include/kvm/arm_hypercalls.h @@ -40,4 +40,11 @@ static inline void smccc_set_retval(struct kvm_vcpu *vcpu, vcpu_set_reg(vcpu, 3, a3); } +struct kvm_one_reg; + +int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu); +int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices); +int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); +int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); + #endif diff --git a/include/kvm/arm_psci.h b/include/kvm/arm_psci.h index 5b58bd2fe088..080c2d0bd6e7 100644 --- a/include/kvm/arm_psci.h +++ b/include/kvm/arm_psci.h @@ -42,11 +42,4 @@ static inline int kvm_psci_version(struct kvm_vcpu *vcpu, struct kvm *kvm) int kvm_psci_call(struct kvm_vcpu *vcpu); -struct kvm_one_reg; - -int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu); -int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices); -int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); -int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); - #endif /* __KVM_ARM_PSCI_H__ */ -- 2.35.1.473.g83b2b277ed-goog