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Diffstat (limited to 'arch/arm64/kernel/cpu_errata.c')
| -rw-r--r-- | arch/arm64/kernel/cpu_errata.c | 1278 |
1 files changed, 1278 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c new file mode 100644 index 000000000..d0b7dd608 --- /dev/null +++ b/arch/arm64/kernel/cpu_errata.c @@ -0,0 +1,1278 @@ +/* + * Contains CPU specific errata definitions + * + * Copyright (C) 2014 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/arm-smccc.h> +#include <linux/psci.h> +#include <linux/types.h> +#include <linux/cpu.h> +#include <asm/cpu.h> +#include <asm/cputype.h> +#include <asm/cpufeature.h> +#include <asm/smp_plat.h> +#include <asm/vectors.h> + +static bool __maybe_unused +is_affected_midr_range(const struct arm64_cpu_capabilities *entry, int scope) +{ + const struct arm64_midr_revidr *fix; + u32 midr = read_cpuid_id(), revidr; + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + if (!is_midr_in_range(midr, &entry->midr_range)) + return false; + + midr &= MIDR_REVISION_MASK | MIDR_VARIANT_MASK; + revidr = read_cpuid(REVIDR_EL1); + for (fix = entry->fixed_revs; fix && fix->revidr_mask; fix++) + if (midr == fix->midr_rv && (revidr & fix->revidr_mask)) + return false; + + return true; +} + +static bool __maybe_unused +is_affected_midr_range_list(const struct arm64_cpu_capabilities *entry, + int scope) +{ + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + return is_midr_in_range_list(read_cpuid_id(), entry->midr_range_list); +} + +static bool __maybe_unused +is_kryo_midr(const struct arm64_cpu_capabilities *entry, int scope) +{ + u32 model; + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + + model = read_cpuid_id(); + model &= MIDR_IMPLEMENTOR_MASK | (0xf00 << MIDR_PARTNUM_SHIFT) | + MIDR_ARCHITECTURE_MASK; + + return model == entry->midr_range.model; +} + +static bool +has_mismatched_cache_type(const struct arm64_cpu_capabilities *entry, + int scope) +{ + u64 mask = CTR_CACHE_MINLINE_MASK; + + /* Skip matching the min line sizes for cache type check */ + if (entry->capability == ARM64_MISMATCHED_CACHE_TYPE) + mask ^= arm64_ftr_reg_ctrel0.strict_mask; + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + return (read_cpuid_cachetype() & mask) != + (arm64_ftr_reg_ctrel0.sys_val & mask); +} + +static void +cpu_enable_trap_ctr_access(const struct arm64_cpu_capabilities *__unused) +{ + sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0); +} + +atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1); + +#include <asm/mmu_context.h> +#include <asm/cacheflush.h> + +DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); + +#ifdef CONFIG_KVM_INDIRECT_VECTORS +extern char __smccc_workaround_1_smc_start[]; +extern char __smccc_workaround_1_smc_end[]; +extern char __smccc_workaround_3_smc_start[]; +extern char __smccc_workaround_3_smc_end[]; +extern char __spectre_bhb_loop_k8_start[]; +extern char __spectre_bhb_loop_k8_end[]; +extern char __spectre_bhb_loop_k24_start[]; +extern char __spectre_bhb_loop_k24_end[]; +extern char __spectre_bhb_loop_k32_start[]; +extern char __spectre_bhb_loop_k32_end[]; +extern char __spectre_bhb_clearbhb_start[]; +extern char __spectre_bhb_clearbhb_end[]; + +static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start, + const char *hyp_vecs_end) +{ + void *dst = lm_alias(__bp_harden_hyp_vecs_start + slot * SZ_2K); + int i; + + for (i = 0; i < SZ_2K; i += 0x80) + memcpy(dst + i, hyp_vecs_start, hyp_vecs_end - hyp_vecs_start); + + __flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K); +} + +static DEFINE_SPINLOCK(bp_lock); +static void install_bp_hardening_cb(bp_hardening_cb_t fn, + const char *hyp_vecs_start, + const char *hyp_vecs_end) +{ + int cpu, slot = -1; + + spin_lock(&bp_lock); + for_each_possible_cpu(cpu) { + if (per_cpu(bp_hardening_data.fn, cpu) == fn) { + slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu); + break; + } + } + + if (slot == -1) { + slot = atomic_inc_return(&arm64_el2_vector_last_slot); + BUG_ON(slot >= BP_HARDEN_EL2_SLOTS); + __copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end); + } + + __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot); + __this_cpu_write(bp_hardening_data.fn, fn); + __this_cpu_write(bp_hardening_data.template_start, hyp_vecs_start); + spin_unlock(&bp_lock); +} +#else +#define __smccc_workaround_1_smc_start NULL +#define __smccc_workaround_1_smc_end NULL + +static void install_bp_hardening_cb(bp_hardening_cb_t fn, + const char *hyp_vecs_start, + const char *hyp_vecs_end) +{ + __this_cpu_write(bp_hardening_data.fn, fn); +} +#endif /* CONFIG_KVM_INDIRECT_VECTORS */ + +#include <uapi/linux/psci.h> +#include <linux/arm-smccc.h> +#include <linux/psci.h> + +static void call_smc_arch_workaround_1(void) +{ + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); +} + +static void call_hvc_arch_workaround_1(void) +{ + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); +} + +static void qcom_link_stack_sanitization(void) +{ + u64 tmp; + + asm volatile("mov %0, x30 \n" + ".rept 16 \n" + "bl . + 4 \n" + ".endr \n" + "mov x30, %0 \n" + : "=&r" (tmp)); +} + +static bool __nospectre_v2; +static int __init parse_nospectre_v2(char *str) +{ + __nospectre_v2 = true; + return 0; +} +early_param("nospectre_v2", parse_nospectre_v2); + +/* + * -1: No workaround + * 0: No workaround required + * 1: Workaround installed + */ +static int detect_harden_bp_fw(void) +{ + bp_hardening_cb_t cb; + void *smccc_start, *smccc_end; + struct arm_smccc_res res; + u32 midr = read_cpuid_id(); + + if (psci_ops.smccc_version == SMCCC_VERSION_1_0) + return -1; + + switch (psci_ops.conduit) { + case PSCI_CONDUIT_HVC: + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_1, &res); + switch ((int)res.a0) { + case 1: + /* Firmware says we're just fine */ + return 0; + case 0: + cb = call_hvc_arch_workaround_1; + /* This is a guest, no need to patch KVM vectors */ + smccc_start = NULL; + smccc_end = NULL; + break; + default: + return -1; + } + break; + + case PSCI_CONDUIT_SMC: + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_1, &res); + switch ((int)res.a0) { + case 1: + /* Firmware says we're just fine */ + return 0; + case 0: + cb = call_smc_arch_workaround_1; + smccc_start = __smccc_workaround_1_smc_start; + smccc_end = __smccc_workaround_1_smc_end; + break; + default: + return -1; + } + break; + + default: + return -1; + } + + if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) || + ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1)) + cb = qcom_link_stack_sanitization; + + if (IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR)) + install_bp_hardening_cb(cb, smccc_start, smccc_end); + + return 1; +} + +DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required); + +int ssbd_state __read_mostly = ARM64_SSBD_KERNEL; +static bool __ssb_safe = true; + +static const struct ssbd_options { + const char *str; + int state; +} ssbd_options[] = { + { "force-on", ARM64_SSBD_FORCE_ENABLE, }, + { "force-off", ARM64_SSBD_FORCE_DISABLE, }, + { "kernel", ARM64_SSBD_KERNEL, }, +}; + +static int __init ssbd_cfg(char *buf) +{ + int i; + + if (!buf || !buf[0]) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(ssbd_options); i++) { + int len = strlen(ssbd_options[i].str); + + if (strncmp(buf, ssbd_options[i].str, len)) + continue; + + ssbd_state = ssbd_options[i].state; + return 0; + } + + return -EINVAL; +} +early_param("ssbd", ssbd_cfg); + +void __init arm64_update_smccc_conduit(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, + int nr_inst) +{ + u32 insn; + + BUG_ON(nr_inst != 1); + + switch (psci_ops.conduit) { + case PSCI_CONDUIT_HVC: + insn = aarch64_insn_get_hvc_value(); + break; + case PSCI_CONDUIT_SMC: + insn = aarch64_insn_get_smc_value(); + break; + default: + return; + } + + *updptr = cpu_to_le32(insn); +} + +void __init arm64_enable_wa2_handling(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, + int nr_inst) +{ + BUG_ON(nr_inst != 1); + /* + * Only allow mitigation on EL1 entry/exit and guest + * ARCH_WORKAROUND_2 handling if the SSBD state allows it to + * be flipped. + */ + if (arm64_get_ssbd_state() == ARM64_SSBD_KERNEL) + *updptr = cpu_to_le32(aarch64_insn_gen_nop()); +} + +void arm64_set_ssbd_mitigation(bool state) +{ + if (!IS_ENABLED(CONFIG_ARM64_SSBD)) { + pr_info_once("SSBD disabled by kernel configuration\n"); + return; + } + + if (this_cpu_has_cap(ARM64_SSBS)) { + if (state) + asm volatile(SET_PSTATE_SSBS(0)); + else + asm volatile(SET_PSTATE_SSBS(1)); + return; + } + + switch (psci_ops.conduit) { + case PSCI_CONDUIT_HVC: + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL); + break; + + case PSCI_CONDUIT_SMC: + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL); + break; + + default: + WARN_ON_ONCE(1); + break; + } +} + +static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, + int scope) +{ + struct arm_smccc_res res; + bool required = true; + s32 val; + bool this_cpu_safe = false; + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + + if (cpu_mitigations_off()) + ssbd_state = ARM64_SSBD_FORCE_DISABLE; + + /* delay setting __ssb_safe until we get a firmware response */ + if (is_midr_in_range_list(read_cpuid_id(), entry->midr_range_list)) + this_cpu_safe = true; + + if (this_cpu_has_cap(ARM64_SSBS)) { + if (!this_cpu_safe) + __ssb_safe = false; + required = false; + goto out_printmsg; + } + + if (psci_ops.smccc_version == SMCCC_VERSION_1_0) { + ssbd_state = ARM64_SSBD_UNKNOWN; + if (!this_cpu_safe) + __ssb_safe = false; + return false; + } + + switch (psci_ops.conduit) { + case PSCI_CONDUIT_HVC: + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_2, &res); + break; + + case PSCI_CONDUIT_SMC: + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_2, &res); + break; + + default: + ssbd_state = ARM64_SSBD_UNKNOWN; + if (!this_cpu_safe) + __ssb_safe = false; + return false; + } + + val = (s32)res.a0; + + switch (val) { + case SMCCC_RET_NOT_SUPPORTED: + ssbd_state = ARM64_SSBD_UNKNOWN; + if (!this_cpu_safe) + __ssb_safe = false; + return false; + + /* machines with mixed mitigation requirements must not return this */ + case SMCCC_RET_NOT_REQUIRED: + pr_info_once("%s mitigation not required\n", entry->desc); + ssbd_state = ARM64_SSBD_MITIGATED; + return false; + + case SMCCC_RET_SUCCESS: + __ssb_safe = false; + required = true; + break; + + case 1: /* Mitigation not required on this CPU */ + required = false; + break; + + default: + WARN_ON(1); + if (!this_cpu_safe) + __ssb_safe = false; + return false; + } + + switch (ssbd_state) { + case ARM64_SSBD_FORCE_DISABLE: + arm64_set_ssbd_mitigation(false); + required = false; + break; + + case ARM64_SSBD_KERNEL: + if (required) { + __this_cpu_write(arm64_ssbd_callback_required, 1); + arm64_set_ssbd_mitigation(true); + } + break; + + case ARM64_SSBD_FORCE_ENABLE: + arm64_set_ssbd_mitigation(true); + required = true; + break; + + default: + WARN_ON(1); + break; + } + +out_printmsg: + switch (ssbd_state) { + case ARM64_SSBD_FORCE_DISABLE: + pr_info_once("%s disabled from command-line\n", entry->desc); + break; + + case ARM64_SSBD_FORCE_ENABLE: + pr_info_once("%s forced from command-line\n", entry->desc); + break; + } + + return required; +} + +/* known invulnerable cores */ +static const struct midr_range arm64_ssb_cpus[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), + {}, +}; + +#ifdef CONFIG_ARM64_ERRATUM_1463225 +DEFINE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa); + +static bool +has_cortex_a76_erratum_1463225(const struct arm64_cpu_capabilities *entry, + int scope) +{ + u32 midr = read_cpuid_id(); + /* Cortex-A76 r0p0 - r3p1 */ + struct midr_range range = MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 3, 1); + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + return is_midr_in_range(midr, &range) && is_kernel_in_hyp_mode(); +} +#endif + +#define CAP_MIDR_RANGE(model, v_min, r_min, v_max, r_max) \ + .matches = is_affected_midr_range, \ + .midr_range = MIDR_RANGE(model, v_min, r_min, v_max, r_max) + +#define CAP_MIDR_ALL_VERSIONS(model) \ + .matches = is_affected_midr_range, \ + .midr_range = MIDR_ALL_VERSIONS(model) + +#define MIDR_FIXED(rev, revidr_mask) \ + .fixed_revs = (struct arm64_midr_revidr[]){{ (rev), (revidr_mask) }, {}} + +#define ERRATA_MIDR_RANGE(model, v_min, r_min, v_max, r_max) \ + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \ + CAP_MIDR_RANGE(model, v_min, r_min, v_max, r_max) + +#define CAP_MIDR_RANGE_LIST(list) \ + .matches = is_affected_midr_range_list, \ + .midr_range_list = list + +/* Errata affecting a range of revisions of given model variant */ +#define ERRATA_MIDR_REV_RANGE(m, var, r_min, r_max) \ + ERRATA_MIDR_RANGE(m, var, r_min, var, r_max) + +/* Errata affecting a single variant/revision of a model */ +#define ERRATA_MIDR_REV(model, var, rev) \ + ERRATA_MIDR_RANGE(model, var, rev, var, rev) + +/* Errata affecting all variants/revisions of a given a model */ +#define ERRATA_MIDR_ALL_VERSIONS(model) \ + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \ + CAP_MIDR_ALL_VERSIONS(model) + +/* Errata affecting a list of midr ranges, with same work around */ +#define ERRATA_MIDR_RANGE_LIST(midr_list) \ + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \ + CAP_MIDR_RANGE_LIST(midr_list) + +/* Track overall mitigation state. We are only mitigated if all cores are ok */ +static bool __hardenbp_enab = true; +static bool __spectrev2_safe = true; + +/* + * Generic helper for handling capabilties with multiple (match,enable) pairs + * of call backs, sharing the same capability bit. + * Iterate over each entry to see if at least one matches. + */ +static bool __maybe_unused +multi_entry_cap_matches(const struct arm64_cpu_capabilities *entry, int scope) +{ + const struct arm64_cpu_capabilities *caps; + + for (caps = entry->match_list; caps->matches; caps++) + if (caps->matches(caps, scope)) + return true; + + return false; +} + +/* + * Take appropriate action for all matching entries in the shared capability + * entry. + */ +static void __maybe_unused +multi_entry_cap_cpu_enable(const struct arm64_cpu_capabilities *entry) +{ + const struct arm64_cpu_capabilities *caps; + + for (caps = entry->match_list; caps->matches; caps++) + if (caps->matches(caps, SCOPE_LOCAL_CPU) && + caps->cpu_enable) + caps->cpu_enable(caps); +} + +/* + * List of CPUs that do not need any Spectre-v2 mitigation at all. + */ +static const struct midr_range spectre_v2_safe_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), + { /* sentinel */ } +}; + +/* + * Track overall bp hardening for all heterogeneous cores in the machine. + * We are only considered "safe" if all booted cores are known safe. + */ +static bool __maybe_unused +check_branch_predictor(const struct arm64_cpu_capabilities *entry, int scope) +{ + int need_wa; + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + + /* If the CPU has CSV2 set, we're safe */ + if (cpuid_feature_extract_unsigned_field(read_cpuid(ID_AA64PFR0_EL1), + ID_AA64PFR0_CSV2_SHIFT)) + return false; + + /* Alternatively, we have a list of unaffected CPUs */ + if (is_midr_in_range_list(read_cpuid_id(), spectre_v2_safe_list)) + return false; + + /* Fallback to firmware detection */ + need_wa = detect_harden_bp_fw(); + if (!need_wa) + return false; + + __spectrev2_safe = false; + + if (!IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR)) { + pr_warn_once("spectrev2 mitigation disabled by kernel configuration\n"); + __hardenbp_enab = false; + return false; + } + + /* forced off */ + if (__nospectre_v2 || cpu_mitigations_off()) { + pr_info_once("spectrev2 mitigation disabled by command line option\n"); + __hardenbp_enab = false; + return false; + } + + if (need_wa < 0) { + pr_warn_once("ARM_SMCCC_ARCH_WORKAROUND_1 missing from firmware\n"); + __hardenbp_enab = false; + } + + return (need_wa > 0); +} + +static void +cpu_enable_branch_predictor_hardening(const struct arm64_cpu_capabilities *cap) +{ + cap->matches(cap, SCOPE_LOCAL_CPU); +} + +static const __maybe_unused struct midr_range tx2_family_cpus[] = { + MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN), + MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2), + {}, +}; + +static bool __maybe_unused +needs_tx2_tvm_workaround(const struct arm64_cpu_capabilities *entry, + int scope) +{ + int i; + + if (!is_affected_midr_range_list(entry, scope) || + !is_hyp_mode_available()) + return false; + + for_each_possible_cpu(i) { + if (MPIDR_AFFINITY_LEVEL(cpu_logical_map(i), 0) != 0) + return true; + } + + return false; +} + +static bool __maybe_unused +has_neoverse_n1_erratum_1542419(const struct arm64_cpu_capabilities *entry, + int scope) +{ + u32 midr = read_cpuid_id(); + bool has_dic = read_cpuid_cachetype() & BIT(CTR_DIC_SHIFT); + const struct midr_range range = MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1); + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + return is_midr_in_range(midr, &range) && has_dic; +} + +#ifdef CONFIG_HARDEN_EL2_VECTORS + +static const struct midr_range arm64_harden_el2_vectors[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), + {}, +}; + +#endif + +const struct arm64_cpu_capabilities arm64_errata[] = { +#if defined(CONFIG_ARM64_ERRATUM_826319) || \ + defined(CONFIG_ARM64_ERRATUM_827319) || \ + defined(CONFIG_ARM64_ERRATUM_824069) + { + /* Cortex-A53 r0p[012] */ + .desc = "ARM errata 826319, 827319, 824069", + .capability = ARM64_WORKAROUND_CLEAN_CACHE, + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 2), + .cpu_enable = cpu_enable_cache_maint_trap, + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_819472 + { + /* Cortex-A53 r0p[01] */ + .desc = "ARM errata 819472", + .capability = ARM64_WORKAROUND_CLEAN_CACHE, + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 1), + .cpu_enable = cpu_enable_cache_maint_trap, + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_832075 + { + /* Cortex-A57 r0p0 - r1p2 */ + .desc = "ARM erratum 832075", + .capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE, + ERRATA_MIDR_RANGE(MIDR_CORTEX_A57, + 0, 0, + 1, 2), + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_834220 + { + /* Cortex-A57 r0p0 - r1p2 */ + .desc = "ARM erratum 834220", + .capability = ARM64_WORKAROUND_834220, + ERRATA_MIDR_RANGE(MIDR_CORTEX_A57, + 0, 0, + 1, 2), + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_843419 + { + /* Cortex-A53 r0p[01234] */ + .desc = "ARM erratum 843419", + .capability = ARM64_WORKAROUND_843419, + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 4), + MIDR_FIXED(0x4, BIT(8)), + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_845719 + { + /* Cortex-A53 r0p[01234] */ + .desc = "ARM erratum 845719", + .capability = ARM64_WORKAROUND_845719, + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 4), + }, +#endif +#ifdef CONFIG_CAVIUM_ERRATUM_23154 + { + /* Cavium ThunderX, pass 1.x */ + .desc = "Cavium erratum 23154", + .capability = ARM64_WORKAROUND_CAVIUM_23154, + ERRATA_MIDR_REV_RANGE(MIDR_THUNDERX, 0, 0, 1), + }, +#endif +#ifdef CONFIG_CAVIUM_ERRATUM_27456 + { + /* Cavium ThunderX, T88 pass 1.x - 2.1 */ + .desc = "Cavium erratum 27456", + .capability = ARM64_WORKAROUND_CAVIUM_27456, + ERRATA_MIDR_RANGE(MIDR_THUNDERX, + 0, 0, + 1, 1), + }, + { + /* Cavium ThunderX, T81 pass 1.0 */ + .desc = "Cavium erratum 27456", + .capability = ARM64_WORKAROUND_CAVIUM_27456, + ERRATA_MIDR_REV(MIDR_THUNDERX_81XX, 0, 0), + }, +#endif +#ifdef CONFIG_CAVIUM_ERRATUM_30115 + { + /* Cavium ThunderX, T88 pass 1.x - 2.2 */ + .desc = "Cavium erratum 30115", + .capability = ARM64_WORKAROUND_CAVIUM_30115, + ERRATA_MIDR_RANGE(MIDR_THUNDERX, + 0, 0, + 1, 2), + }, + { + /* Cavium ThunderX, T81 pass 1.0 - 1.2 */ + .desc = "Cavium erratum 30115", + .capability = ARM64_WORKAROUND_CAVIUM_30115, + ERRATA_MIDR_REV_RANGE(MIDR_THUNDERX_81XX, 0, 0, 2), + }, + { + /* Cavium ThunderX, T83 pass 1.0 */ + .desc = "Cavium erratum 30115", + .capability = ARM64_WORKAROUND_CAVIUM_30115, + ERRATA_MIDR_REV(MIDR_THUNDERX_83XX, 0, 0), + }, +#endif + { + .desc = "Mismatched cache line size", + .capability = ARM64_MISMATCHED_CACHE_LINE_SIZE, + .matches = has_mismatched_cache_type, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .cpu_enable = cpu_enable_trap_ctr_access, + }, + { + .desc = "Mismatched cache type", + .capability = ARM64_MISMATCHED_CACHE_TYPE, + .matches = has_mismatched_cache_type, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .cpu_enable = cpu_enable_trap_ctr_access, + }, +#ifdef CONFIG_QCOM_FALKOR_ERRATUM_1003 + { + .desc = "Qualcomm Technologies Falkor erratum 1003", + .capability = ARM64_WORKAROUND_QCOM_FALKOR_E1003, + ERRATA_MIDR_REV(MIDR_QCOM_FALKOR_V1, 0, 0), + }, + { + .desc = "Qualcomm Technologies Kryo erratum 1003", + .capability = ARM64_WORKAROUND_QCOM_FALKOR_E1003, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .midr_range.model = MIDR_QCOM_KRYO, + .matches = is_kryo_midr, + }, +#endif +#ifdef CONFIG_QCOM_FALKOR_ERRATUM_1009 + { + .desc = "Qualcomm Technologies Falkor erratum 1009", + .capability = ARM64_WORKAROUND_REPEAT_TLBI, + ERRATA_MIDR_REV(MIDR_QCOM_FALKOR_V1, 0, 0), + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_858921 + { + /* Cortex-A73 all versions */ + .desc = "ARM erratum 858921", + .capability = ARM64_WORKAROUND_858921, + ERRATA_MIDR_ALL_VERSIONS(MIDR_CORTEX_A73), + }, +#endif + { + .desc = "Branch predictor hardening", + .capability = ARM64_HARDEN_BRANCH_PREDICTOR, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .matches = check_branch_predictor, + .cpu_enable = cpu_enable_branch_predictor_hardening, + }, +#ifdef CONFIG_HARDEN_EL2_VECTORS + { + .desc = "EL2 vector hardening", + .capability = ARM64_HARDEN_EL2_VECTORS, + ERRATA_MIDR_RANGE_LIST(arm64_harden_el2_vectors), + }, +#endif + { + .desc = "Speculative Store Bypass Disable", + .capability = ARM64_SSBD, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .matches = has_ssbd_mitigation, + .midr_range_list = arm64_ssb_cpus, + }, + { + .desc = "Spectre-BHB", + .capability = ARM64_SPECTRE_BHB, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .matches = is_spectre_bhb_affected, + .cpu_enable = spectre_bhb_enable_mitigation, + }, +#ifdef CONFIG_ARM64_ERRATUM_1463225 + { + .desc = "ARM erratum 1463225", + .capability = ARM64_WORKAROUND_1463225, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .matches = has_cortex_a76_erratum_1463225, + }, +#endif +#ifdef CONFIG_CAVIUM_TX2_ERRATUM_219 + { + .desc = "Cavium ThunderX2 erratum 219 (KVM guest sysreg trapping)", + .capability = ARM64_WORKAROUND_CAVIUM_TX2_219_TVM, + ERRATA_MIDR_RANGE_LIST(tx2_family_cpus), + .matches = needs_tx2_tvm_workaround, + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_1542419 + { + /* we depend on the firmware portion for correctness */ + .desc = "ARM erratum 1542419 (kernel portion)", + .capability = ARM64_WORKAROUND_1542419, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .matches = has_neoverse_n1_erratum_1542419, + .cpu_enable = cpu_enable_trap_ctr_access, + }, +#endif + { + } +}; + +ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "Mitigation: __user pointer sanitization\n"); +} + +static const char *get_bhb_affected_string(enum mitigation_state bhb_state) +{ + switch (bhb_state) { + case SPECTRE_UNAFFECTED: + return ""; + default: + case SPECTRE_VULNERABLE: + return ", but not BHB"; + case SPECTRE_MITIGATED: + return ", BHB"; + } +} + +ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, + char *buf) +{ + enum mitigation_state bhb_state = arm64_get_spectre_bhb_state(); + const char *bhb_str = get_bhb_affected_string(bhb_state); + const char *v2_str = "Branch predictor hardening"; + + if (__spectrev2_safe) { + if (bhb_state == SPECTRE_UNAFFECTED) + return sprintf(buf, "Not affected\n"); + + /* + * Platforms affected by Spectre-BHB can't report + * "Not affected" for Spectre-v2. + */ + v2_str = "CSV2"; + } + + if (__hardenbp_enab) + return sprintf(buf, "Mitigation: %s%s\n", v2_str, bhb_str); + + return sprintf(buf, "Vulnerable\n"); +} + +ssize_t cpu_show_spec_store_bypass(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (__ssb_safe) + return sprintf(buf, "Not affected\n"); + + switch (ssbd_state) { + case ARM64_SSBD_KERNEL: + case ARM64_SSBD_FORCE_ENABLE: + if (IS_ENABLED(CONFIG_ARM64_SSBD)) + return sprintf(buf, + "Mitigation: Speculative Store Bypass disabled via prctl\n"); + } + + return sprintf(buf, "Vulnerable\n"); +} + +/* + * We try to ensure that the mitigation state can never change as the result of + * onlining a late CPU. + */ +static void update_mitigation_state(enum mitigation_state *oldp, + enum mitigation_state new) +{ + enum mitigation_state state; + + do { + state = READ_ONCE(*oldp); + if (new <= state) + break; + } while (cmpxchg_relaxed(oldp, state, new) != state); +} + +/* + * Spectre BHB. + * + * A CPU is either: + * - Mitigated by a branchy loop a CPU specific number of times, and listed + * in our "loop mitigated list". + * - Mitigated in software by the firmware Spectre v2 call. + * - Has the ClearBHB instruction to perform the mitigation. + * - Has the 'Exception Clears Branch History Buffer' (ECBHB) feature, so no + * software mitigation in the vectors is needed. + * - Has CSV2.3, so is unaffected. + */ +static enum mitigation_state spectre_bhb_state; + +enum mitigation_state arm64_get_spectre_bhb_state(void) +{ + return spectre_bhb_state; +} + +/* + * This must be called with SCOPE_LOCAL_CPU for each type of CPU, before any + * SCOPE_SYSTEM call will give the right answer. + */ +u8 spectre_bhb_loop_affected(int scope) +{ + u8 k = 0; + static u8 max_bhb_k; + + if (scope == SCOPE_LOCAL_CPU) { + static const struct midr_range spectre_bhb_k32_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A78), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A78C), + MIDR_ALL_VERSIONS(MIDR_CORTEX_X1), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A710), + MIDR_ALL_VERSIONS(MIDR_CORTEX_X2), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V1), + {}, + }; + static const struct midr_range spectre_bhb_k24_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A77), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A76), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1), + {}, + }; + static const struct midr_range spectre_bhb_k8_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), + {}, + }; + + if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k32_list)) + k = 32; + else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k24_list)) + k = 24; + else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k8_list)) + k = 8; + + max_bhb_k = max(max_bhb_k, k); + } else { + k = max_bhb_k; + } + + return k; +} + +static enum mitigation_state spectre_bhb_get_cpu_fw_mitigation_state(void) +{ + int ret; + struct arm_smccc_res res; + + if (psci_ops.smccc_version == SMCCC_VERSION_1_0) + return SPECTRE_VULNERABLE; + + switch (psci_ops.conduit) { + case PSCI_CONDUIT_HVC: + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_3, &res); + break; + + case PSCI_CONDUIT_SMC: + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_3, &res); + break; + + default: + return SPECTRE_VULNERABLE; + } + + ret = res.a0; + switch (ret) { + case SMCCC_RET_SUCCESS: + return SPECTRE_MITIGATED; + case SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED: + return SPECTRE_UNAFFECTED; + default: + case SMCCC_RET_NOT_SUPPORTED: + return SPECTRE_VULNERABLE; + } +} + +static bool is_spectre_bhb_fw_affected(int scope) +{ + static bool system_affected; + enum mitigation_state fw_state; + bool has_smccc = (psci_ops.smccc_version >= SMCCC_VERSION_1_1); + static const struct midr_range spectre_bhb_firmware_mitigated_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A73), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A75), + {}, + }; + bool cpu_in_list = is_midr_in_range_list(read_cpuid_id(), + spectre_bhb_firmware_mitigated_list); + + if (scope != SCOPE_LOCAL_CPU) + return system_affected; + + fw_state = spectre_bhb_get_cpu_fw_mitigation_state(); + if (cpu_in_list || (has_smccc && fw_state == SPECTRE_MITIGATED)) { + system_affected = true; + return true; + } + + return false; +} + +static bool supports_ecbhb(int scope) +{ + u64 mmfr1; + + if (scope == SCOPE_LOCAL_CPU) + mmfr1 = read_sysreg_s(SYS_ID_AA64MMFR1_EL1); + else + mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); + + return cpuid_feature_extract_unsigned_field(mmfr1, + ID_AA64MMFR1_ECBHB_SHIFT); +} + +bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, + int scope) +{ + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + + if (supports_csv2p3(scope)) + return false; + + if (supports_clearbhb(scope)) + return true; + + if (spectre_bhb_loop_affected(scope)) + return true; + + if (is_spectre_bhb_fw_affected(scope)) + return true; + + return false; +} + +static void this_cpu_set_vectors(enum arm64_bp_harden_el1_vectors slot) +{ + const char *v = arm64_get_bp_hardening_vector(slot); + + if (slot < 0) + return; + + __this_cpu_write(this_cpu_vector, v); + + /* + * When KPTI is in use, the vectors are switched when exiting to + * user-space. + */ + if (arm64_kernel_unmapped_at_el0()) + return; + + write_sysreg(v, vbar_el1); + isb(); +} + +#ifdef CONFIG_KVM_INDIRECT_VECTORS +static const char *kvm_bhb_get_vecs_end(const char *start) +{ + if (start == __smccc_workaround_3_smc_start) + return __smccc_workaround_3_smc_end; + else if (start == __spectre_bhb_loop_k8_start) + return __spectre_bhb_loop_k8_end; + else if (start == __spectre_bhb_loop_k24_start) + return __spectre_bhb_loop_k24_end; + else if (start == __spectre_bhb_loop_k32_start) + return __spectre_bhb_loop_k32_end; + else if (start == __spectre_bhb_clearbhb_start) + return __spectre_bhb_clearbhb_end; + + return NULL; +} + +static void kvm_setup_bhb_slot(const char *hyp_vecs_start) +{ + int cpu, slot = -1; + const char *hyp_vecs_end; + + if (!IS_ENABLED(CONFIG_KVM) || !is_hyp_mode_available()) + return; + + hyp_vecs_end = kvm_bhb_get_vecs_end(hyp_vecs_start); + if (WARN_ON_ONCE(!hyp_vecs_start || !hyp_vecs_end)) + return; + + spin_lock(&bp_lock); + for_each_possible_cpu(cpu) { + if (per_cpu(bp_hardening_data.template_start, cpu) == hyp_vecs_start) { + slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu); + break; + } + } + + if (slot == -1) { + slot = atomic_inc_return(&arm64_el2_vector_last_slot); + BUG_ON(slot >= BP_HARDEN_EL2_SLOTS); + __copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end); + } + + __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot); + __this_cpu_write(bp_hardening_data.template_start, hyp_vecs_start); + spin_unlock(&bp_lock); +} +#else +#define __smccc_workaround_3_smc_start NULL +#define __spectre_bhb_loop_k8_start NULL +#define __spectre_bhb_loop_k24_start NULL +#define __spectre_bhb_loop_k32_start NULL +#define __spectre_bhb_clearbhb_start NULL + +static void kvm_setup_bhb_slot(const char *hyp_vecs_start) { }; +#endif + +void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry) +{ + enum mitigation_state fw_state, state = SPECTRE_VULNERABLE; + + if (!is_spectre_bhb_affected(entry, SCOPE_LOCAL_CPU)) + return; + + if (!__spectrev2_safe && !__hardenbp_enab) { + /* No point mitigating Spectre-BHB alone. */ + } else if (!IS_ENABLED(CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY)) { + pr_info_once("spectre-bhb mitigation disabled by compile time option\n"); + } else if (cpu_mitigations_off()) { + pr_info_once("spectre-bhb mitigation disabled by command line option\n"); + } else if (supports_ecbhb(SCOPE_LOCAL_CPU)) { + state = SPECTRE_MITIGATED; + } else if (supports_clearbhb(SCOPE_LOCAL_CPU)) { + kvm_setup_bhb_slot(__spectre_bhb_clearbhb_start); + this_cpu_set_vectors(EL1_VECTOR_BHB_CLEAR_INSN); + + state = SPECTRE_MITIGATED; + } else if (spectre_bhb_loop_affected(SCOPE_LOCAL_CPU)) { + switch (spectre_bhb_loop_affected(SCOPE_SYSTEM)) { + case 8: + kvm_setup_bhb_slot(__spectre_bhb_loop_k8_start); + break; + case 24: + kvm_setup_bhb_slot(__spectre_bhb_loop_k24_start); + break; + case 32: + kvm_setup_bhb_slot(__spectre_bhb_loop_k32_start); + break; + default: + WARN_ON_ONCE(1); + } + this_cpu_set_vectors(EL1_VECTOR_BHB_LOOP); + + state = SPECTRE_MITIGATED; + } else if (is_spectre_bhb_fw_affected(SCOPE_LOCAL_CPU)) { + fw_state = spectre_bhb_get_cpu_fw_mitigation_state(); + if (fw_state == SPECTRE_MITIGATED) { + kvm_setup_bhb_slot(__smccc_workaround_3_smc_start); + this_cpu_set_vectors(EL1_VECTOR_BHB_FW); + + /* + * With WA3 in the vectors, the WA1 calls can be + * removed. + */ + __this_cpu_write(bp_hardening_data.fn, NULL); + + state = SPECTRE_MITIGATED; + } + } + + update_mitigation_state(&spectre_bhb_state, state); +} + +/* Patched to correct the immediate */ +void __init spectre_bhb_patch_loop_iter(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, int nr_inst) +{ + u8 rd; + u32 insn; + u16 loop_count = spectre_bhb_loop_affected(SCOPE_SYSTEM); + + BUG_ON(nr_inst != 1); /* MOV -> MOV */ + + if (!IS_ENABLED(CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY)) + return; + + insn = le32_to_cpu(*origptr); + rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD, insn); + insn = aarch64_insn_gen_movewide(rd, loop_count, 0, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_MOVEWIDE_ZERO); + *updptr++ = cpu_to_le32(insn); +} |