diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt index ac9489fad31b8..47df2c25302ac 100644 --- a/Documentation/arm64/silicon-errata.txt +++ b/Documentation/arm64/silicon-errata.txt @@ -55,6 +55,7 @@ stable kernels. | ARM | Cortex-A57 | #834220 | ARM64_ERRATUM_834220 | | ARM | Cortex-A72 | #853709 | N/A | | ARM | Cortex-A55 | #1024718 | ARM64_ERRATUM_1024718 | +| ARM | Cortex-A76 | #1188873 | ARM64_ERRATUM_1188873 | | ARM | MMU-500 | #841119,#826419 | N/A | | | | | | | Cavium | ThunderX ITS | #22375, #24313 | CAVIUM_ERRATUM_22375 | diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 6c0957c67d207..f2b10986ab889 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -751,15 +751,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted. loops can be debugged more effectively on production systems. - clocksource.arm_arch_timer.fsl-a008585= - [ARM64] - Format: - Enable/disable the workaround of Freescale/NXP - erratum A-008585. This can be useful for KVM - guests, if the guest device tree doesn't show the - erratum. If unspecified, the workaround is - enabled based on the device tree. - clearcpuid=BITNUM [X86] Disable CPUID feature X for the kernel. See arch/x86/include/asm/cpufeatures.h for the valid bit diff --git a/Makefile b/Makefile index c1d4ddadbcb51..72a8c786cb777 100644 --- a/Makefile +++ b/Makefile @@ -1,6 +1,6 @@ VERSION = 4 PATCHLEVEL = 9 -SUBLEVEL = 309 +SUBLEVEL = 310 EXTRAVERSION = NAME = Roaring Lionus diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 2fda7e905754b..82c71a147f21d 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -349,4 +349,9 @@ static inline int kvm_arm_have_ssbd(void) return KVM_SSBD_UNKNOWN; } +static inline bool kvm_arm_spectre_bhb_mitigated(void) +{ + /* 32bit guests don't need firmware for this */ + return false; +} #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index 83365bec04b69..a262c175456d3 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -431,6 +431,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) break; } break; + case ARM_SMCCC_ARCH_WORKAROUND_3: + if (kvm_arm_spectre_bhb_mitigated()) + val = SMCCC_RET_SUCCESS; + break; } break; default: diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b12275be0e139..6d12c3b787771 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -441,6 +441,20 @@ config ARM64_ERRATUM_1024718 If unsure, say Y. +config ARM64_ERRATUM_1188873 + bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result" + default y + depends on COMPAT + select ARM_ARCH_TIMER_OOL_WORKAROUND + help + This option adds work arounds for ARM Cortex-A76 erratum 1188873 + + Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could cause + register corruption when accessing the timer registers from + AArch32 userspace. + + If unsure, say Y. + config CAVIUM_ERRATUM_22375 bool "Cavium erratum 22375, 24313" default y @@ -785,6 +799,16 @@ config ARM64_SSBD If unsure, say Y. +config MITIGATE_SPECTRE_BRANCH_HISTORY + bool "Mitigate Spectre style attacks against branch history" if EXPERT + default y + depends on HARDEN_BRANCH_PREDICTOR || !KVM + help + Speculation attacks against some high-performance processors can + make use of branch history to influence future speculation. + When taking an exception from user-space, a sequence of branches + or a firmware call overwrites the branch history. + menuconfig ARMV8_DEPRECATED bool "Emulate deprecated/obsolete ARMv8 instructions" depends on COMPAT diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h index eaa5bbe3fa875..1b0d7e994e0c7 100644 --- a/arch/arm64/include/asm/arch_timer.h +++ b/arch/arm64/include/asm/arch_timer.h @@ -29,41 +29,35 @@ #include -#if IS_ENABLED(CONFIG_FSL_ERRATUM_A008585) +#if IS_ENABLED(CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND) extern struct static_key_false arch_timer_read_ool_enabled; -#define needs_fsl_a008585_workaround() \ +#define needs_unstable_timer_counter_workaround() \ static_branch_unlikely(&arch_timer_read_ool_enabled) #else -#define needs_fsl_a008585_workaround() false +#define needs_unstable_timer_counter_workaround() false #endif -u32 __fsl_a008585_read_cntp_tval_el0(void); -u32 __fsl_a008585_read_cntv_tval_el0(void); -u64 __fsl_a008585_read_cntvct_el0(void); +enum arch_timer_erratum_match_type { + ate_match_dt, + ate_match_local_cap_id, +}; -/* - * The number of retries is an arbitrary value well beyond the highest number - * of iterations the loop has been observed to take. - */ -#define __fsl_a008585_read_reg(reg) ({ \ - u64 _old, _new; \ - int _retries = 200; \ - \ - do { \ - _old = read_sysreg(reg); \ - _new = read_sysreg(reg); \ - _retries--; \ - } while (unlikely(_old != _new) && _retries); \ - \ - WARN_ON_ONCE(!_retries); \ - _new; \ -}) +struct arch_timer_erratum_workaround { + enum arch_timer_erratum_match_type match_type; + const void *id; + const char *desc; + u32 (*read_cntp_tval_el0)(void); + u32 (*read_cntv_tval_el0)(void); + u64 (*read_cntvct_el0)(void); +}; + +extern const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround; #define arch_timer_reg_read_stable(reg) \ ({ \ u64 _val; \ - if (needs_fsl_a008585_workaround()) \ - _val = __fsl_a008585_read_##reg(); \ + if (needs_unstable_timer_counter_workaround()) \ + _val = timer_unstable_counter_workaround->read_##reg();\ else \ _val = read_sysreg(reg); \ _val; \ diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 3f85bbcd7e408..a6aaeb871d5fa 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -94,6 +94,13 @@ hint #20 .endm +/* + * Clear Branch History instruction + */ + .macro clearbhb + hint #22 + .endm + /* * Sanitise a 64-bit bounded index wrt speculation, returning zero if out * of bounds. @@ -494,4 +501,31 @@ alternative_endif .Ldone\@: .endm + .macro __mitigate_spectre_bhb_loop tmp +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY +alternative_cb spectre_bhb_patch_loop_iter + mov \tmp, #32 // Patched to correct the immediate +alternative_cb_end +.Lspectre_bhb_loop\@: + b . + 4 + subs \tmp, \tmp, #1 + b.ne .Lspectre_bhb_loop\@ + dsb nsh + isb +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + .endm + + /* Save/restores x0-x3 to the stack */ + .macro __mitigate_spectre_bhb_fw +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY + stp x0, x1, [sp, #-16]! + stp x2, x3, [sp, #-16]! + mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3 +alternative_cb arm64_update_smccc_conduit + nop // Patched to SMC/HVC #0 +alternative_cb_end + ldp x2, x3, [sp], #16 + ldp x0, x1, [sp], #16 +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + .endm #endif /* __ASM_ASSEMBLER_H */ diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h index 889226b4c6e1c..c7f17e663e729 100644 --- a/arch/arm64/include/asm/cpu.h +++ b/arch/arm64/include/asm/cpu.h @@ -36,6 +36,7 @@ struct cpuinfo_arm64 { u64 reg_id_aa64dfr1; u64 reg_id_aa64isar0; u64 reg_id_aa64isar1; + u64 reg_id_aa64isar2; u64 reg_id_aa64mmfr0; u64 reg_id_aa64mmfr1; u64 reg_id_aa64mmfr2; diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index 8c7c4b23a8b18..9935e55a3cc75 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -38,7 +38,9 @@ #define ARM64_HARDEN_BRANCH_PREDICTOR 17 #define ARM64_SSBD 18 #define ARM64_MISMATCHED_CACHE_TYPE 19 +#define ARM64_WORKAROUND_1188873 20 +#define ARM64_SPECTRE_BHB 21 -#define ARM64_NCAPS 20 +#define ARM64_NCAPS 22 #endif /* __ASM_CPUCAPS_H */ diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index e7bef3d936d87..58a32511da8f1 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -10,6 +10,7 @@ #define __ASM_CPUFEATURE_H #include +#include #include #include @@ -66,24 +67,173 @@ struct arm64_ftr_reg { extern struct arm64_ftr_reg arm64_ftr_reg_ctrel0; -/* scope of capability check */ -enum { - SCOPE_SYSTEM, - SCOPE_LOCAL_CPU, -}; +/* + * CPU capabilities: + * + * We use arm64_cpu_capabilities to represent system features, errata work + * arounds (both used internally by kernel and tracked in cpu_hwcaps) and + * ELF HWCAPs (which are exposed to user). + * + * To support systems with heterogeneous CPUs, we need to make sure that we + * detect the capabilities correctly on the system and take appropriate + * measures to ensure there are no incompatibilities. + * + * This comment tries to explain how we treat the capabilities. + * Each capability has the following list of attributes : + * + * 1) Scope of Detection : The system detects a given capability by + * performing some checks at runtime. This could be, e.g, checking the + * value of a field in CPU ID feature register or checking the cpu + * model. The capability provides a call back ( @matches() ) to + * perform the check. Scope defines how the checks should be performed. + * There are two cases: + * + * a) SCOPE_LOCAL_CPU: check all the CPUs and "detect" if at least one + * matches. This implies, we have to run the check on all the + * booting CPUs, until the system decides that state of the + * capability is finalised. (See section 2 below) + * Or + * b) SCOPE_SYSTEM: check all the CPUs and "detect" if all the CPUs + * matches. This implies, we run the check only once, when the + * system decides to finalise the state of the capability. If the + * capability relies on a field in one of the CPU ID feature + * registers, we use the sanitised value of the register from the + * CPU feature infrastructure to make the decision. + * + * The process of detection is usually denoted by "update" capability + * state in the code. + * + * 2) Finalise the state : The kernel should finalise the state of a + * capability at some point during its execution and take necessary + * actions if any. Usually, this is done, after all the boot-time + * enabled CPUs are brought up by the kernel, so that it can make + * better decision based on the available set of CPUs. However, there + * are some special cases, where the action is taken during the early + * boot by the primary boot CPU. (e.g, running the kernel at EL2 with + * Virtualisation Host Extensions). The kernel usually disallows any + * changes to the state of a capability once it finalises the capability + * and takes any action, as it may be impossible to execute the actions + * safely. A CPU brought up after a capability is "finalised" is + * referred to as "Late CPU" w.r.t the capability. e.g, all secondary + * CPUs are treated "late CPUs" for capabilities determined by the boot + * CPU. + * + * 3) Verification: When a CPU is brought online (e.g, by user or by the + * kernel), the kernel should make sure that it is safe to use the CPU, + * by verifying that the CPU is compliant with the state of the + * capabilities finalised already. This happens via : + * + * secondary_start_kernel()-> check_local_cpu_capabilities() + * + * As explained in (2) above, capabilities could be finalised at + * different points in the execution. Each CPU is verified against the + * "finalised" capabilities and if there is a conflict, the kernel takes + * an action, based on the severity (e.g, a CPU could be prevented from + * booting or cause a kernel panic). The CPU is allowed to "affect" the + * state of the capability, if it has not been finalised already. + * See section 5 for more details on conflicts. + * + * 4) Action: As mentioned in (2), the kernel can take an action for each + * detected capability, on all CPUs on the system. Appropriate actions + * include, turning on an architectural feature, modifying the control + * registers (e.g, SCTLR, TCR etc.) or patching the kernel via + * alternatives. The kernel patching is batched and performed at later + * point. The actions are always initiated only after the capability + * is finalised. This is usally denoted by "enabling" the capability. + * The actions are initiated as follows : + * a) Action is triggered on all online CPUs, after the capability is + * finalised, invoked within the stop_machine() context from + * enable_cpu_capabilitie(). + * + * b) Any late CPU, brought up after (1), the action is triggered via: + * + * check_local_cpu_capabilities() -> verify_local_cpu_capabilities() + * + * 5) Conflicts: Based on the state of the capability on a late CPU vs. + * the system state, we could have the following combinations : + * + * x-----------------------------x + * | Type | System | Late CPU | + * |-----------------------------| + * | a | y | n | + * |-----------------------------| + * | b | n | y | + * x-----------------------------x + * + * Two separate flag bits are defined to indicate whether each kind of + * conflict can be allowed: + * ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU - Case(a) is allowed + * ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU - Case(b) is allowed + * + * Case (a) is not permitted for a capability that the system requires + * all CPUs to have in order for the capability to be enabled. This is + * typical for capabilities that represent enhanced functionality. + * + * Case (b) is not permitted for a capability that must be enabled + * during boot if any CPU in the system requires it in order to run + * safely. This is typical for erratum work arounds that cannot be + * enabled after the corresponding capability is finalised. + * + * In some non-typical cases either both (a) and (b), or neither, + * should be permitted. This can be described by including neither + * or both flags in the capability's type field. + */ + + +/* Decide how the capability is detected. On a local CPU vs System wide */ +#define ARM64_CPUCAP_SCOPE_LOCAL_CPU ((u16)BIT(0)) +#define ARM64_CPUCAP_SCOPE_SYSTEM ((u16)BIT(1)) +#define ARM64_CPUCAP_SCOPE_MASK \ + (ARM64_CPUCAP_SCOPE_SYSTEM | \ + ARM64_CPUCAP_SCOPE_LOCAL_CPU) + +#define SCOPE_SYSTEM ARM64_CPUCAP_SCOPE_SYSTEM +#define SCOPE_LOCAL_CPU ARM64_CPUCAP_SCOPE_LOCAL_CPU + +/* + * Is it permitted for a late CPU to have this capability when system + * hasn't already enabled it ? + */ +#define ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU ((u16)BIT(4)) +/* Is it safe for a late CPU to miss this capability when system has it */ +#define ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU ((u16)BIT(5)) + +/* + * CPU errata workarounds that need to be enabled at boot time if one or + * more CPUs in the system requires it. When one of these capabilities + * has been enabled, it is safe to allow any CPU to boot that doesn't + * require the workaround. However, it is not safe if a "late" CPU + * requires a workaround and the system hasn't enabled it already. + */ +#define ARM64_CPUCAP_LOCAL_CPU_ERRATUM \ + (ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU) +/* + * CPU feature detected at boot time based on system-wide value of a + * feature. It is safe for a late CPU to have this feature even though + * the system hasn't enabled it, although the featuer will not be used + * by Linux in this case. If the system has enabled this feature already, + * then every late CPU must have it. + */ +#define ARM64_CPUCAP_SYSTEM_FEATURE \ + (ARM64_CPUCAP_SCOPE_SYSTEM | ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU) struct arm64_cpu_capabilities { const char *desc; u16 capability; - int def_scope; /* default scope */ + u16 type; bool (*matches)(const struct arm64_cpu_capabilities *caps, int scope); - int (*enable)(void *); /* Called on all active CPUs */ + /* + * Take the appropriate actions to enable this capability for this CPU. + * For each successfully booted CPU, this method is called for each + * globally detected capability. + */ + void (*cpu_enable)(const struct arm64_cpu_capabilities *cap); union { struct { /* To be used for erratum handling only */ - u32 midr_model; - u32 midr_range_min, midr_range_max; + struct midr_range midr_range; }; + const struct midr_range *midr_range_list; struct { /* Feature register checking */ u32 sys_reg; u8 field_pos; @@ -95,6 +245,23 @@ struct arm64_cpu_capabilities { }; }; +static inline int cpucap_default_scope(const struct arm64_cpu_capabilities *cap) +{ + return cap->type & ARM64_CPUCAP_SCOPE_MASK; +} + +static inline bool +cpucap_late_cpu_optional(const struct arm64_cpu_capabilities *cap) +{ + return !!(cap->type & ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU); +} + +static inline bool +cpucap_late_cpu_permitted(const struct arm64_cpu_capabilities *cap) +{ + return !!(cap->type & ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU); +} + extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS); extern struct static_key_false cpu_hwcap_keys[ARM64_NCAPS]; extern struct static_key_false arm64_const_caps_ready; @@ -195,15 +362,8 @@ static inline bool id_aa64pfr0_32bit_el0(u64 pfr0) } void __init setup_cpu_features(void); - -void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, - const char *info); -void enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps); void check_local_cpu_capabilities(void); -void update_cpu_errata_workarounds(void); -void __init enable_errata_workarounds(void); -void verify_local_cpu_errata_workarounds(void); u64 read_system_reg(u32 id); @@ -212,6 +372,34 @@ static inline bool cpu_supports_mixed_endian_el0(void) return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1)); } +static inline bool supports_csv2p3(int scope) +{ + u64 pfr0; + u8 csv2_val; + + if (scope == SCOPE_LOCAL_CPU) + pfr0 = read_sysreg_s(SYS_ID_AA64PFR0_EL1); + else + pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1); + + csv2_val = cpuid_feature_extract_unsigned_field(pfr0, + ID_AA64PFR0_CSV2_SHIFT); + return csv2_val == 3; +} + +static inline bool supports_clearbhb(int scope) +{ + u64 isar2; + + if (scope == SCOPE_LOCAL_CPU) + isar2 = read_sysreg_s(SYS_ID_AA64ISAR2_EL1); + else + isar2 = read_system_reg(SYS_ID_AA64ISAR2_EL1); + + return cpuid_feature_extract_unsigned_field(isar2, + ID_AA64ISAR2_CLEARBHB_SHIFT); +} + static inline bool system_supports_32bit_el0(void) { return cpus_have_const_cap(ARM64_HAS_32BIT_EL0); @@ -244,6 +432,18 @@ void arm64_set_ssbd_mitigation(bool state); static inline void arm64_set_ssbd_mitigation(bool state) {} #endif +/* Watch out, ordering is important here. */ +enum mitigation_state { + SPECTRE_UNAFFECTED, + SPECTRE_MITIGATED, + SPECTRE_VULNERABLE, +}; + +enum mitigation_state arm64_get_spectre_bhb_state(void); +bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, int scope); +u8 spectre_bhb_loop_affected(int scope); +void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry); + #endif /* __ASSEMBLY__ */ #endif diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index 39d1db68748db..7ffa41caa4178 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -83,6 +83,18 @@ #define ARM_CPU_PART_CORTEX_A53 0xD03 #define ARM_CPU_PART_CORTEX_A73 0xD09 #define ARM_CPU_PART_CORTEX_A75 0xD0A +#define ARM_CPU_PART_CORTEX_A35 0xD04 +#define ARM_CPU_PART_CORTEX_A55 0xD05 +#define ARM_CPU_PART_CORTEX_A76 0xD0B +#define ARM_CPU_PART_NEOVERSE_N1 0xD0C +#define ARM_CPU_PART_CORTEX_A77 0xD0D +#define ARM_CPU_PART_NEOVERSE_V1 0xD40 +#define ARM_CPU_PART_CORTEX_A78 0xD41 +#define ARM_CPU_PART_CORTEX_X1 0xD44 +#define ARM_CPU_PART_CORTEX_A710 0xD47 +#define ARM_CPU_PART_CORTEX_X2 0xD48 +#define ARM_CPU_PART_NEOVERSE_N2 0xD49 +#define ARM_CPU_PART_CORTEX_A78C 0xD4B #define APM_CPU_PART_POTENZA 0x000 @@ -98,6 +110,18 @@ #define MIDR_CORTEX_A72 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A72) #define MIDR_CORTEX_A73 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A73) #define MIDR_CORTEX_A75 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A75) +#define MIDR_CORTEX_A35 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A35) +#define MIDR_CORTEX_A55 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A55) +#define MIDR_CORTEX_A76 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76) +#define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1) +#define MIDR_CORTEX_A77 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77) +#define MIDR_NEOVERSE_V1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_V1) +#define MIDR_CORTEX_A78 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78) +#define MIDR_CORTEX_X1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X1) +#define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710) +#define MIDR_CORTEX_X2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X2) +#define MIDR_NEOVERSE_N2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N2) +#define MIDR_CORTEX_A78C MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78C) #define MIDR_THUNDERX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX) #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX) #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2) @@ -109,6 +133,45 @@ #define read_cpuid(reg) read_sysreg_s(SYS_ ## reg) +/* + * Represent a range of MIDR values for a given CPU model and a + * range of variant/revision values. + * + * @model - CPU model as defined by MIDR_CPU_MODEL + * @rv_min - Minimum value for the revision/variant as defined by + * MIDR_CPU_VAR_REV + * @rv_max - Maximum value for the variant/revision for the range. + */ +struct midr_range { + u32 model; + u32 rv_min; + u32 rv_max; +}; + +#define MIDR_RANGE(m, v_min, r_min, v_max, r_max) \ + { \ + .model = m, \ + .rv_min = MIDR_CPU_VAR_REV(v_min, r_min), \ + .rv_max = MIDR_CPU_VAR_REV(v_max, r_max), \ + } + +#define MIDR_ALL_VERSIONS(m) MIDR_RANGE(m, 0, 0, 0xf, 0xf) + +static inline bool is_midr_in_range(u32 midr, struct midr_range const *range) +{ + return MIDR_IS_CPU_MODEL_RANGE(midr, range->model, + range->rv_min, range->rv_max); +} + +static inline bool +is_midr_in_range_list(u32 midr, struct midr_range const *ranges) +{ + while (ranges->model) + if (is_midr_in_range(midr, ranges++)) + return true; + return false; +} + /* * The CPU ID never changes at run time, so we might as well tell the * compiler that it's constant. Use this function to read the CPU ID diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h index d8e58051f32d4..4ffe0d698fa72 100644 --- a/arch/arm64/include/asm/fixmap.h +++ b/arch/arm64/include/asm/fixmap.h @@ -53,9 +53,11 @@ enum fixed_addresses { FIX_TEXT_POKE0, #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 + FIX_ENTRY_TRAMP_TEXT3, + FIX_ENTRY_TRAMP_TEXT2, + FIX_ENTRY_TRAMP_TEXT1, FIX_ENTRY_TRAMP_DATA, - FIX_ENTRY_TRAMP_TEXT, -#define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT)) +#define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT1)) #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */ __end_of_permanent_fixed_addresses, diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h index bc853663dd517..aecc07e09a18b 100644 --- a/arch/arm64/include/asm/insn.h +++ b/arch/arm64/include/asm/insn.h @@ -332,6 +332,8 @@ bool aarch64_insn_is_branch(u32 insn); u64 aarch64_insn_decode_immediate(enum aarch64_insn_imm_type type, u32 insn); u32 aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type, u32 insn, u64 imm); +u32 aarch64_insn_decode_register(enum aarch64_insn_register_type type, + u32 insn); u32 aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr, enum aarch64_insn_branch_type type); u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr, diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index a152a7bbc85ab..a75f02e5f0fdc 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -452,4 +452,8 @@ static inline int kvm_arm_have_ssbd(void) } } +static inline bool kvm_arm_spectre_bhb_mitigated(void) +{ + return arm64_get_spectre_bhb_state() == SPECTRE_MITIGATED; +} #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index ff721659eb94b..4a2c958548568 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -362,7 +362,7 @@ static inline void *kvm_get_hyp_vector(void) struct bp_hardening_data *data = arm64_get_bp_hardening_data(); void *vect = kvm_ksym_ref(__kvm_hyp_vector); - if (data->fn) { + if (data->template_start) { vect = __bp_harden_hyp_vecs_start + data->hyp_vectors_slot * SZ_2K; diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h index 6ac34c75f4e13..f4377b005cba9 100644 --- a/arch/arm64/include/asm/mmu.h +++ b/arch/arm64/include/asm/mmu.h @@ -34,7 +34,7 @@ typedef struct { */ #define ASID(mm) ((mm)->context.id.counter & 0xffff) -static inline bool arm64_kernel_unmapped_at_el0(void) +static __always_inline bool arm64_kernel_unmapped_at_el0(void) { return IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0) && cpus_have_const_cap(ARM64_UNMAP_KERNEL_AT_EL0); @@ -45,6 +45,12 @@ typedef void (*bp_hardening_cb_t)(void); struct bp_hardening_data { int hyp_vectors_slot; bp_hardening_cb_t fn; + + /* + * template_start is only used by the BHB mitigation to identify the + * hyp_vectors_slot sequence. + */ + const char *template_start; }; #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 9ee660013e5cb..367141e05c346 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -37,6 +37,7 @@ #include #include +#include #include #include #include @@ -219,9 +220,8 @@ static inline void spin_lock_prefetch(const void *ptr) #endif -int cpu_enable_pan(void *__unused); -int cpu_enable_uao(void *__unused); -int cpu_enable_cache_maint_trap(void *__unused); +void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused); +void cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused); #endif /* __ASSEMBLY__ */ #endif /* __ASM_PROCESSOR_H */ diff --git a/arch/arm64/include/asm/sections.h b/arch/arm64/include/asm/sections.h index 4e7e7067afdb0..09ebd37d5aa3c 100644 --- a/arch/arm64/include/asm/sections.h +++ b/arch/arm64/include/asm/sections.h @@ -26,5 +26,11 @@ extern char __hyp_text_start[], __hyp_text_end[]; extern char __idmap_text_start[], __idmap_text_end[]; extern char __irqentry_text_start[], __irqentry_text_end[]; extern char __mmuoff_data_start[], __mmuoff_data_end[]; +extern char __entry_tramp_text_start[], __entry_tramp_text_end[]; + +static inline size_t entry_tramp_text_size(void) +{ + return __entry_tramp_text_end - __entry_tramp_text_start; +} #endif /* __ASM_SECTIONS_H */ diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index ae1b31d02784c..46e97be12e028 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -70,6 +70,7 @@ #define SYS_ID_AA64ISAR0_EL1 sys_reg(3, 0, 0, 6, 0) #define SYS_ID_AA64ISAR1_EL1 sys_reg(3, 0, 0, 6, 1) +#define SYS_ID_AA64ISAR2_EL1 sys_reg(3, 0, 0, 6, 2) #define SYS_ID_AA64MMFR0_EL1 sys_reg(3, 0, 0, 7, 0) #define SYS_ID_AA64MMFR1_EL1 sys_reg(3, 0, 0, 7, 1) @@ -173,6 +174,9 @@ #define ID_AA64ISAR0_SHA1_SHIFT 8 #define ID_AA64ISAR0_AES_SHIFT 4 +/* id_aa64isar2 */ +#define ID_AA64ISAR2_CLEARBHB_SHIFT 28 + /* id_aa64pfr0 */ #define ID_AA64PFR0_CSV3_SHIFT 60 #define ID_AA64PFR0_CSV2_SHIFT 56 @@ -211,6 +215,7 @@ #define ID_AA64MMFR0_TGRAN16_SUPPORTED 0x1 /* id_aa64mmfr1 */ +#define ID_AA64MMFR1_ECBHB_SHIFT 60 #define ID_AA64MMFR1_PAN_SHIFT 20 #define ID_AA64MMFR1_LOR_SHIFT 16 #define ID_AA64MMFR1_HPD_SHIFT 12 diff --git a/arch/arm64/include/asm/vectors.h b/arch/arm64/include/asm/vectors.h new file mode 100644 index 0000000000000..695583b9a145b --- /dev/null +++ b/arch/arm64/include/asm/vectors.h @@ -0,0 +1,74 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2022 ARM Ltd. + */ +#ifndef __ASM_VECTORS_H +#define __ASM_VECTORS_H + +#include +#include + +#include +#include + +extern char vectors[]; +extern char tramp_vectors[]; +extern char __bp_harden_el1_vectors[]; + +/* + * Note: the order of this enum corresponds to two arrays in entry.S: + * tramp_vecs and __bp_harden_el1_vectors. By default the canonical + * 'full fat' vectors are used directly. + */ +enum arm64_bp_harden_el1_vectors { +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY + /* + * Perform the BHB loop mitigation, before branching to the canonical + * vectors. + */ + EL1_VECTOR_BHB_LOOP, + + /* + * Make the SMC call for firmware mitigation, before branching to the + * canonical vectors. + */ + EL1_VECTOR_BHB_FW, + + /* + * Use the ClearBHB instruction, before branching to the canonical + * vectors. + */ + EL1_VECTOR_BHB_CLEAR_INSN, +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + + /* + * Remap the kernel before branching to the canonical vectors. + */ + EL1_VECTOR_KPTI, +}; + +#ifndef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY +#define EL1_VECTOR_BHB_LOOP -1 +#define EL1_VECTOR_BHB_FW -1 +#define EL1_VECTOR_BHB_CLEAR_INSN -1 +#endif /* !CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + +/* The vectors to use on return from EL0. e.g. to remap the kernel */ +DECLARE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector); + +#ifndef CONFIG_UNMAP_KERNEL_AT_EL0 +#define TRAMP_VALIAS 0 +#endif + +static inline const char * +arm64_get_bp_hardening_vector(enum arm64_bp_harden_el1_vectors slot) +{ + if (arm64_kernel_unmapped_at_el0()) + return (char *)TRAMP_VALIAS + SZ_2K * slot; + + WARN_ON_ONCE(slot == EL1_VECTOR_KPTI); + + return __bp_harden_el1_vectors + SZ_2K * slot; +} + +#endif /* __ASM_VECTORS_H */ diff --git a/arch/arm64/kernel/bpi.S b/arch/arm64/kernel/bpi.S index dc4eb154e33b5..d3fd8bf42d868 100644 --- a/arch/arm64/kernel/bpi.S +++ b/arch/arm64/kernel/bpi.S @@ -73,3 +73,58 @@ ENTRY(__smccc_workaround_1_smc_end) ENTRY(__smccc_workaround_1_hvc_start) smccc_workaround_1 hvc ENTRY(__smccc_workaround_1_hvc_end) + +ENTRY(__smccc_workaround_3_smc_start) + sub sp, sp, #(8 * 4) + stp x2, x3, [sp, #(8 * 0)] + stp x0, x1, [sp, #(8 * 2)] + mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3 + smc #0 + ldp x2, x3, [sp, #(8 * 0)] + ldp x0, x1, [sp, #(8 * 2)] + add sp, sp, #(8 * 4) +ENTRY(__smccc_workaround_3_smc_end) + +ENTRY(__spectre_bhb_loop_k8_start) + sub sp, sp, #(8 * 2) + stp x0, x1, [sp, #(8 * 0)] + mov x0, #8 +2: b . + 4 + subs x0, x0, #1 + b.ne 2b + dsb nsh + isb + ldp x0, x1, [sp, #(8 * 0)] + add sp, sp, #(8 * 2) +ENTRY(__spectre_bhb_loop_k8_end) + +ENTRY(__spectre_bhb_loop_k24_start) + sub sp, sp, #(8 * 2) + stp x0, x1, [sp, #(8 * 0)] + mov x0, #24 +2: b . + 4 + subs x0, x0, #1 + b.ne 2b + dsb nsh + isb + ldp x0, x1, [sp, #(8 * 0)] + add sp, sp, #(8 * 2) +ENTRY(__spectre_bhb_loop_k24_end) + +ENTRY(__spectre_bhb_loop_k32_start) + sub sp, sp, #(8 * 2) + stp x0, x1, [sp, #(8 * 0)] + mov x0, #32 +2: b . + 4 + subs x0, x0, #1 + b.ne 2b + dsb nsh + isb + ldp x0, x1, [sp, #(8 * 0)] + add sp, sp, #(8 * 2) +ENTRY(__spectre_bhb_loop_k32_end) + +ENTRY(__spectre_bhb_clearbhb_start) + hint #22 /* aka clearbhb */ + isb +ENTRY(__spectre_bhb_clearbhb_end) diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index 3b680a32886b9..f0cdf21b1006b 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -23,14 +23,23 @@ #include #include #include +#include static bool __maybe_unused is_affected_midr_range(const struct arm64_cpu_capabilities *entry, int scope) { + u32 midr = read_cpuid_id(); + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); - return MIDR_IS_CPU_MODEL_RANGE(read_cpuid_id(), entry->midr_model, - entry->midr_range_min, - entry->midr_range_max); + return is_midr_in_range(midr, &entry->midr_range); +} + +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 @@ -48,17 +57,18 @@ has_mismatched_cache_type(const struct arm64_cpu_capabilities *entry, (arm64_ftr_reg_ctrel0.sys_val & mask); } -static int cpu_enable_trap_ctr_access(void *__unused) +static void +cpu_enable_trap_ctr_access(const struct arm64_cpu_capabilities *__unused) { /* Clear SCTLR_EL1.UCT */ config_sctlr_el1(SCTLR_EL1_UCT, 0); - return 0; } #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR #include #include +static bool __hardenbp_enab; DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); #ifdef CONFIG_KVM @@ -66,6 +76,16 @@ extern char __smccc_workaround_1_smc_start[]; extern char __smccc_workaround_1_smc_end[]; extern char __smccc_workaround_1_hvc_start[]; extern char __smccc_workaround_1_hvc_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) @@ -79,12 +99,14 @@ static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start, flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K); } +static DEFINE_SPINLOCK(bp_lock); +static int last_slot = -1; + static void __install_bp_hardening_cb(bp_hardening_cb_t fn, const char *hyp_vecs_start, const char *hyp_vecs_end) { - static int last_slot = -1; - static DEFINE_SPINLOCK(bp_lock); + int cpu, slot = -1; spin_lock(&bp_lock); @@ -105,6 +127,8 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn, __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); + __hardenbp_enab = true; spin_unlock(&bp_lock); } #else @@ -118,6 +142,7 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn, const char *hyp_vecs_end) { __this_cpu_write(bp_hardening_data.fn, fn); + __hardenbp_enab = true; } #endif /* CONFIG_KVM */ @@ -152,25 +177,25 @@ static void call_hvc_arch_workaround_1(void) arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); } -static int enable_smccc_arch_workaround_1(void *data) +static void +enable_smccc_arch_workaround_1(const struct arm64_cpu_capabilities *entry) { - const struct arm64_cpu_capabilities *entry = data; bp_hardening_cb_t cb; void *smccc_start, *smccc_end; struct arm_smccc_res res; if (!entry->matches(entry, SCOPE_LOCAL_CPU)) - return 0; + return; if (psci_ops.smccc_version == SMCCC_VERSION_1_0) - return 0; + return; 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); if ((int)res.a0 < 0) - return 0; + return; cb = call_hvc_arch_workaround_1; smccc_start = __smccc_workaround_1_hvc_start; smccc_end = __smccc_workaround_1_hvc_end; @@ -180,22 +205,44 @@ static int enable_smccc_arch_workaround_1(void *data) arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, ARM_SMCCC_ARCH_WORKAROUND_1, &res); if ((int)res.a0 < 0) - return 0; + return; cb = call_smc_arch_workaround_1; smccc_start = __smccc_workaround_1_smc_start; smccc_end = __smccc_workaround_1_smc_end; break; default: - return 0; + return; } install_bp_hardening_cb(entry, cb, smccc_start, smccc_end); - return 0; + return; } #endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */ +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); +} + #ifdef CONFIG_ARM64_SSBD DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required); @@ -231,28 +278,6 @@ static int __init ssbd_cfg(char *buf) } 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) @@ -368,19 +393,60 @@ static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, } #endif /* CONFIG_ARM64_SSBD */ -#define MIDR_RANGE(model, min, max) \ - .def_scope = SCOPE_LOCAL_CPU, \ - .matches = is_affected_midr_range, \ - .midr_model = model, \ - .midr_range_min = min, \ - .midr_range_max = max +#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 -#define MIDR_ALL_VERSIONS(model) \ - .def_scope = SCOPE_LOCAL_CPU, \ - .matches = is_affected_midr_range, \ - .midr_model = model, \ - .midr_range_min = 0, \ - .midr_range_max = (MIDR_VARIANT_MASK | MIDR_REVISION_MASK) +/* 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) + +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR + +/* + * List of CPUs where we need to issue a psci call to + * harden the branch predictor. + */ +static const struct midr_range arm64_bp_harden_smccc_cpus[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A73), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A75), + MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN), + MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2), + {}, +}; + +#endif const struct arm64_cpu_capabilities arm64_errata[] = { #if defined(CONFIG_ARM64_ERRATUM_826319) || \ @@ -390,8 +456,8 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cortex-A53 r0p[012] */ .desc = "ARM errata 826319, 827319, 824069", .capability = ARM64_WORKAROUND_CLEAN_CACHE, - MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x02), - .enable = cpu_enable_cache_maint_trap, + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 2), + .cpu_enable = cpu_enable_cache_maint_trap, }, #endif #ifdef CONFIG_ARM64_ERRATUM_819472 @@ -399,8 +465,8 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cortex-A53 r0p[01] */ .desc = "ARM errata 819472", .capability = ARM64_WORKAROUND_CLEAN_CACHE, - MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x01), - .enable = cpu_enable_cache_maint_trap, + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 1), + .cpu_enable = cpu_enable_cache_maint_trap, }, #endif #ifdef CONFIG_ARM64_ERRATUM_832075 @@ -408,8 +474,9 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cortex-A57 r0p0 - r1p2 */ .desc = "ARM erratum 832075", .capability = ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE, - MIDR_RANGE(MIDR_CORTEX_A57, 0x00, - (1 << MIDR_VARIANT_SHIFT) | 2), + ERRATA_MIDR_RANGE(MIDR_CORTEX_A57, + 0, 0, + 1, 2), }, #endif #ifdef CONFIG_ARM64_ERRATUM_834220 @@ -417,8 +484,9 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cortex-A57 r0p0 - r1p2 */ .desc = "ARM erratum 834220", .capability = ARM64_WORKAROUND_834220, - MIDR_RANGE(MIDR_CORTEX_A57, 0x00, - (1 << MIDR_VARIANT_SHIFT) | 2), + ERRATA_MIDR_RANGE(MIDR_CORTEX_A57, + 0, 0, + 1, 2), }, #endif #ifdef CONFIG_ARM64_ERRATUM_845719 @@ -426,7 +494,7 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cortex-A53 r0p[01234] */ .desc = "ARM erratum 845719", .capability = ARM64_WORKAROUND_845719, - MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x04), + ERRATA_MIDR_REV_RANGE(MIDR_CORTEX_A53, 0, 0, 4), }, #endif #ifdef CONFIG_CAVIUM_ERRATUM_23154 @@ -434,7 +502,7 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cavium ThunderX, pass 1.x */ .desc = "Cavium erratum 23154", .capability = ARM64_WORKAROUND_CAVIUM_23154, - MIDR_RANGE(MIDR_THUNDERX, 0x00, 0x01), + ERRATA_MIDR_REV_RANGE(MIDR_THUNDERX, 0, 0, 1), }, #endif #ifdef CONFIG_CAVIUM_ERRATUM_27456 @@ -442,103 +510,402 @@ const struct arm64_cpu_capabilities arm64_errata[] = { /* Cavium ThunderX, T88 pass 1.x - 2.1 */ .desc = "Cavium erratum 27456", .capability = ARM64_WORKAROUND_CAVIUM_27456, - MIDR_RANGE(MIDR_THUNDERX, 0x00, - (1 << MIDR_VARIANT_SHIFT) | 1), + ERRATA_MIDR_RANGE(MIDR_THUNDERX, + 0, 0, + 1, 1), }, { /* Cavium ThunderX, T81 pass 1.0 */ .desc = "Cavium erratum 27456", .capability = ARM64_WORKAROUND_CAVIUM_27456, - MIDR_RANGE(MIDR_THUNDERX_81XX, 0x00, 0x00), + ERRATA_MIDR_REV(MIDR_THUNDERX_81XX, 0, 0), }, #endif { .desc = "Mismatched cache line size", .capability = ARM64_MISMATCHED_CACHE_LINE_SIZE, .matches = has_mismatched_cache_type, - .def_scope = SCOPE_LOCAL_CPU, - .enable = cpu_enable_trap_ctr_access, + .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, - .def_scope = SCOPE_LOCAL_CPU, - .enable = cpu_enable_trap_ctr_access, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .cpu_enable = cpu_enable_trap_ctr_access, }, #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR { .capability = ARM64_HARDEN_BRANCH_PREDICTOR, - MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), - .enable = enable_smccc_arch_workaround_1, - }, - { - .capability = ARM64_HARDEN_BRANCH_PREDICTOR, - MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), - .enable = enable_smccc_arch_workaround_1, - }, - { - .capability = ARM64_HARDEN_BRANCH_PREDICTOR, - MIDR_ALL_VERSIONS(MIDR_CORTEX_A73), - .enable = enable_smccc_arch_workaround_1, - }, - { - .capability = ARM64_HARDEN_BRANCH_PREDICTOR, - MIDR_ALL_VERSIONS(MIDR_CORTEX_A75), - .enable = enable_smccc_arch_workaround_1, - }, - { - .capability = ARM64_HARDEN_BRANCH_PREDICTOR, - MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN), - .enable = enable_smccc_arch_workaround_1, - }, - { - .capability = ARM64_HARDEN_BRANCH_PREDICTOR, - MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2), - .enable = enable_smccc_arch_workaround_1, + ERRATA_MIDR_RANGE_LIST(arm64_bp_harden_smccc_cpus), + .cpu_enable = enable_smccc_arch_workaround_1, }, #endif #ifdef CONFIG_ARM64_SSBD { .desc = "Speculative Store Bypass Disable", - .def_scope = SCOPE_LOCAL_CPU, + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, .capability = ARM64_SSBD, .matches = has_ssbd_mitigation, }, #endif +#ifdef CONFIG_ARM64_ERRATUM_1188873 + { + /* Cortex-A76 r0p0 to r2p0 */ + .desc = "ARM erratum 1188873", + .capability = ARM64_WORKAROUND_1188873, + ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0), + }, +#endif + { + .desc = "Spectre-BHB", + .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, + .capability = ARM64_SPECTRE_BHB, + .matches = is_spectre_bhb_affected, +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY + .cpu_enable = spectre_bhb_enable_mitigation, +#endif + }, { } }; /* - * The CPU Errata work arounds are detected and applied at boot time - * and the related information is freed soon after. If the new CPU requires - * an errata not detected at boot, fail this CPU. + * We try to ensure that the mitigation state can never change as the result of + * onlining a late CPU. */ -void verify_local_cpu_errata_workarounds(void) +static void __maybe_unused update_mitigation_state(enum mitigation_state *oldp, + enum mitigation_state new) { - const struct arm64_cpu_capabilities *caps = arm64_errata; - - for (; caps->matches; caps++) { - if (cpus_have_cap(caps->capability)) { - if (caps->enable) - caps->enable((void *)caps); - } else if (caps->matches(caps, SCOPE_LOCAL_CPU)) { - pr_crit("CPU%d: Requires work around for %s, not detected" - " at boot time\n", - smp_processor_id(), - caps->desc ? : "an erratum"); - cpu_die_early(); + 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 __maybe_unused supports_ecbhb(int scope) +{ + u64 mmfr1; + + if (scope == SCOPE_LOCAL_CPU) + mmfr1 = read_sysreg_s(SYS_ID_AA64MMFR1_EL1); + else + mmfr1 = read_system_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; +} + +#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR +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 +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) { + last_slot++; + BUG_ON(((__bp_harden_hyp_vecs_end - __bp_harden_hyp_vecs_start) + / SZ_2K) <= last_slot); + slot = last_slot; + __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 /* CONFIG_KVM */ -void update_cpu_errata_workarounds(void) +static bool is_spectrev2_safe(void) { - update_cpu_capabilities(arm64_errata, "enabling workaround for"); + return !is_midr_in_range_list(read_cpuid_id(), + arm64_bp_harden_smccc_cpus); } -void __init enable_errata_workarounds(void) +void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry) { - enable_cpu_capabilities(arm64_errata); + enum mitigation_state fw_state, state = SPECTRE_VULNERABLE; + + if (!is_spectre_bhb_affected(entry, SCOPE_LOCAL_CPU)) + return; + + if (!is_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); } +#endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 8cf001baee219..9b7e7d2f236ee 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -20,15 +20,18 @@ #include #include +#include #include #include #include + #include #include #include #include #include #include +#include #include unsigned long elf_hwcap __read_mostly; @@ -49,6 +52,8 @@ unsigned int compat_elf_hwcap2 __read_mostly; DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS); EXPORT_SYMBOL(cpu_hwcaps); +DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors; + DEFINE_STATIC_KEY_ARRAY_FALSE(cpu_hwcap_keys, ARM64_NCAPS); EXPORT_SYMBOL(cpu_hwcap_keys); @@ -93,6 +98,11 @@ static const struct arm64_ftr_bits ftr_id_aa64isar0[] = { ARM64_FTR_END, }; +static const struct arm64_ftr_bits ftr_id_aa64isar2[] = { + ARM64_FTR_BITS(FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0), + ARM64_FTR_END, +}; + static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = { ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0), @@ -327,6 +337,7 @@ static const struct __ftr_reg_entry { /* Op1 = 0, CRn = 0, CRm = 6 */ ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0), ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_aa64raz), + ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2), /* Op1 = 0, CRn = 0, CRm = 7 */ ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0), @@ -439,6 +450,9 @@ static void __init init_cpu_ftr_reg(u32 sys_reg, u64 new) reg->strict_mask = strict_mask; } +extern const struct arm64_cpu_capabilities arm64_errata[]; +static void update_cpu_errata_workarounds(void); + void __init init_cpu_features(struct cpuinfo_arm64 *info) { /* Before we start using the tables, make sure it is sorted */ @@ -451,6 +465,7 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info) init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1); init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0); init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1); + init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2); init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0); init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1); init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2); @@ -476,6 +491,11 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info) init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2); } + /* + * Run the errata work around checks on the boot CPU, once we have + * initialised the cpu feature infrastructure. + */ + update_cpu_errata_workarounds(); } static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new) @@ -557,6 +577,8 @@ void update_cpu_features(int cpu, info->reg_id_aa64isar0, boot->reg_id_aa64isar0); taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu, info->reg_id_aa64isar1, boot->reg_id_aa64isar1); + taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu, + info->reg_id_aa64isar2, boot->reg_id_aa64isar2); /* * Differing PARange support is fine as long as all peripherals and @@ -676,6 +698,7 @@ static u64 __raw_read_system_reg(u32 sys_id) case SYS_ID_AA64MMFR2_EL1: return read_cpuid(ID_AA64MMFR2_EL1); case SYS_ID_AA64ISAR0_EL1: return read_cpuid(ID_AA64ISAR0_EL1); case SYS_ID_AA64ISAR1_EL1: return read_cpuid(ID_AA64ISAR1_EL1); + case SYS_ID_AA64ISAR2_EL1: return read_cpuid(ID_AA64ISAR2_EL1); case SYS_CNTFRQ_EL0: return read_cpuid(CNTFRQ_EL0); case SYS_CTR_EL0: return read_cpuid(CTR_EL0); @@ -728,13 +751,11 @@ static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, static bool has_no_hw_prefetch(const struct arm64_cpu_capabilities *entry, int __unused) { u32 midr = read_cpuid_id(); - u32 rv_min, rv_max; /* Cavium ThunderX pass 1.x and 2.x */ - rv_min = 0; - rv_max = (1 << MIDR_VARIANT_SHIFT) | MIDR_REVISION_MASK; - - return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, rv_min, rv_max); + return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX, + MIDR_CPU_VAR_REV(0, 0), + MIDR_CPU_VAR_REV(1, MIDR_REVISION_MASK)); } static bool runs_at_el2(const struct arm64_cpu_capabilities *entry, int __unused) @@ -761,6 +782,17 @@ static int __kpti_forced; /* 0: not forced, >0: forced on, <0: forced off */ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, int __unused) { + /* List of CPUs that are not vulnerable and don't need KPTI */ + static const struct midr_range kpti_safe_list[] = { + MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2), + MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A73), + }; char const *str = "command line option"; u64 pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1); @@ -786,23 +818,16 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, return true; /* Don't force KPTI for CPUs that are not vulnerable */ - switch (read_cpuid_id() & MIDR_CPU_MODEL_MASK) { - case MIDR_CAVIUM_THUNDERX2: - case MIDR_BRCM_VULCAN: - case MIDR_CORTEX_A53: - case MIDR_CORTEX_A55: - case MIDR_CORTEX_A57: - case MIDR_CORTEX_A72: - case MIDR_CORTEX_A73: + if (is_midr_in_range_list(read_cpuid_id(), kpti_safe_list)) return false; - } /* Defer to CPU feature registers */ return !cpuid_feature_extract_unsigned_field(pfr0, ID_AA64PFR0_CSV3_SHIFT); } -static int kpti_install_ng_mappings(void *__unused) +static void +kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused) { typedef void (kpti_remap_fn)(int, int, phys_addr_t); extern kpti_remap_fn idmap_kpti_install_ng_mappings; @@ -811,8 +836,14 @@ static int kpti_install_ng_mappings(void *__unused) static bool kpti_applied = false; int cpu = smp_processor_id(); + if (__this_cpu_read(this_cpu_vector) == vectors) { + const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI); + + __this_cpu_write(this_cpu_vector, v); + } + if (kpti_applied) - return 0; + return; remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings); @@ -823,7 +854,7 @@ static int kpti_install_ng_mappings(void *__unused) if (!cpu) kpti_applied = true; - return 0; + return; } static int __init parse_kpti(char *str) @@ -840,7 +871,7 @@ static int __init parse_kpti(char *str) early_param("kpti", parse_kpti); #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */ -static int cpu_copy_el2regs(void *__unused) +static void cpu_copy_el2regs(const struct arm64_cpu_capabilities *__unused) { /* * Copy register values that aren't redirected by hardware. @@ -852,15 +883,13 @@ static int cpu_copy_el2regs(void *__unused) */ if (!alternatives_applied) write_sysreg(read_sysreg(tpidr_el1), tpidr_el2); - - return 0; } static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "GIC system register CPU interface", .capability = ARM64_HAS_SYSREG_GIC_CPUIF, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_useable_gicv3_cpuif, .sys_reg = SYS_ID_AA64PFR0_EL1, .field_pos = ID_AA64PFR0_GIC_SHIFT, @@ -871,20 +900,20 @@ static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "Privileged Access Never", .capability = ARM64_HAS_PAN, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64MMFR1_EL1, .field_pos = ID_AA64MMFR1_PAN_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = 1, - .enable = cpu_enable_pan, + .cpu_enable = cpu_enable_pan, }, #endif /* CONFIG_ARM64_PAN */ #if defined(CONFIG_AS_LSE) && defined(CONFIG_ARM64_LSE_ATOMICS) { .desc = "LSE atomic instructions", .capability = ARM64_HAS_LSE_ATOMICS, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64ISAR0_EL1, .field_pos = ID_AA64ISAR0_ATOMICS_SHIFT, @@ -895,39 +924,42 @@ static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "Software prefetching using PRFM", .capability = ARM64_HAS_NO_HW_PREFETCH, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_no_hw_prefetch, }, #ifdef CONFIG_ARM64_UAO { .desc = "User Access Override", .capability = ARM64_HAS_UAO, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64MMFR2_EL1, .field_pos = ID_AA64MMFR2_UAO_SHIFT, .min_field_value = 1, - .enable = cpu_enable_uao, + /* + * We rely on stop_machine() calling uao_thread_switch() to set + * UAO immediately after patching. + */ }, #endif /* CONFIG_ARM64_UAO */ #ifdef CONFIG_ARM64_PAN { .capability = ARM64_ALT_PAN_NOT_UAO, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = cpufeature_pan_not_uao, }, #endif /* CONFIG_ARM64_PAN */ { .desc = "Virtualization Host Extensions", .capability = ARM64_HAS_VIRT_HOST_EXTN, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = runs_at_el2, - .enable = cpu_copy_el2regs, + .cpu_enable = cpu_copy_el2regs, }, { .desc = "32-bit EL0 Support", .capability = ARM64_HAS_32BIT_EL0, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64PFR0_EL1, .sign = FTR_UNSIGNED, @@ -937,31 +969,31 @@ static const struct arm64_cpu_capabilities arm64_features[] = { { .desc = "Reduced HYP mapping offset", .capability = ARM64_HYP_OFFSET_LOW, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = hyp_offset_low, }, #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 { .desc = "Kernel page table isolation (KPTI)", .capability = ARM64_UNMAP_KERNEL_AT_EL0, - .def_scope = SCOPE_SYSTEM, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = unmap_kernel_at_el0, - .enable = kpti_install_ng_mappings, + .cpu_enable = kpti_install_ng_mappings, }, #endif {}, }; -#define HWCAP_CAP(reg, field, s, min_value, type, cap) \ +#define HWCAP_CAP(reg, field, s, min_value, cap_type, cap) \ { \ .desc = #cap, \ - .def_scope = SCOPE_SYSTEM, \ + .type = ARM64_CPUCAP_SYSTEM_FEATURE, \ .matches = has_cpuid_feature, \ .sys_reg = reg, \ .field_pos = field, \ .sign = s, \ .min_field_value = min_value, \ - .hwcap_type = type, \ + .hwcap_type = cap_type, \ .hwcap = cap, \ } @@ -1038,7 +1070,7 @@ static bool cpus_have_elf_hwcap(const struct arm64_cpu_capabilities *cap) static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps) { for (; hwcaps->matches; hwcaps++) - if (hwcaps->matches(hwcaps, hwcaps->def_scope)) + if (hwcaps->matches(hwcaps, cpucap_default_scope(hwcaps))) cap_set_elf_hwcap(hwcaps); } @@ -1061,11 +1093,11 @@ static bool __this_cpu_has_cap(const struct arm64_cpu_capabilities *cap_array, return false; } -void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, - const char *info) +static void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, + const char *info) { for (; caps->matches; caps++) { - if (!caps->matches(caps, caps->def_scope)) + if (!caps->matches(caps, cpucap_default_scope(caps))) continue; if (!cpus_have_cap(caps->capability) && caps->desc) @@ -1074,11 +1106,20 @@ void update_cpu_capabilities(const struct arm64_cpu_capabilities *caps, } } +static int __enable_cpu_capability(void *arg) +{ + const struct arm64_cpu_capabilities *cap = arg; + + cap->cpu_enable(cap); + return 0; +} + /* * Run through the enabled capabilities and enable() it on all active * CPUs */ -void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps) +static void __init +enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps) { for (; caps->matches; caps++) { unsigned int num = caps->capability; @@ -1089,14 +1130,15 @@ void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps) /* Ensure cpus_have_const_cap(num) works */ static_branch_enable(&cpu_hwcap_keys[num]); - if (caps->enable) { + if (caps->cpu_enable) { /* * Use stop_machine() as it schedules the work allowing * us to modify PSTATE, instead of on_each_cpu() which * uses an IPI, giving us a PSTATE that disappears when * we return. */ - stop_machine(caps->enable, (void *)caps, cpu_online_mask); + stop_machine(__enable_cpu_capability, (void *)caps, + cpu_online_mask); } } } @@ -1154,11 +1196,44 @@ verify_local_cpu_features(const struct arm64_cpu_capabilities *caps_list) smp_processor_id(), caps->desc); cpu_die_early(); } - if (caps->enable) - caps->enable((void *)caps); + if (caps->cpu_enable) + caps->cpu_enable(caps); } } +/* + * The CPU Errata work arounds are detected and applied at boot time + * and the related information is freed soon after. If the new CPU requires + * an errata not detected at boot, fail this CPU. + */ +static void verify_local_cpu_errata_workarounds(void) +{ + const struct arm64_cpu_capabilities *caps = arm64_errata; + + for (; caps->matches; caps++) { + if (cpus_have_cap(caps->capability)) { + if (caps->cpu_enable) + caps->cpu_enable(caps); + } else if (caps->matches(caps, SCOPE_LOCAL_CPU)) { + pr_crit("CPU%d: Requires work around for %s, not detected" + " at boot time\n", + smp_processor_id(), + caps->desc ? : "an erratum"); + cpu_die_early(); + } + } +} + +static void update_cpu_errata_workarounds(void) +{ + update_cpu_capabilities(arm64_errata, "enabling workaround for"); +} + +static void __init enable_errata_workarounds(void) +{ + enable_cpu_capabilities(arm64_errata); +} + /* * Run through the enabled system capabilities and enable() it on this CPU. * The capabilities were decided based on the available CPUs at the boot time. diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index b3d5b3e8fbcb1..4c09f87650f4b 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -335,6 +335,7 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info) info->reg_id_aa64dfr1 = read_cpuid(ID_AA64DFR1_EL1); info->reg_id_aa64isar0 = read_cpuid(ID_AA64ISAR0_EL1); info->reg_id_aa64isar1 = read_cpuid(ID_AA64ISAR1_EL1); + info->reg_id_aa64isar2 = read_cpuid(ID_AA64ISAR2_EL1); info->reg_id_aa64mmfr0 = read_cpuid(ID_AA64MMFR0_EL1); info->reg_id_aa64mmfr1 = read_cpuid(ID_AA64MMFR1_EL1); info->reg_id_aa64mmfr2 = read_cpuid(ID_AA64MMFR2_EL1); diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index ca978d7d98eb4..1f79abb1e5ddb 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -74,26 +74,33 @@ .macro kernel_ventry, el, label, regsize = 64 .align 7 -#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 -alternative_if ARM64_UNMAP_KERNEL_AT_EL0 +.Lventry_start\@: .if \el == 0 + /* + * This must be the first instruction of the EL0 vector entries. It is + * skipped by the trampoline vectors, to trigger the cleanup. + */ + b .Lskip_tramp_vectors_cleanup\@ .if \regsize == 64 mrs x30, tpidrro_el0 msr tpidrro_el0, xzr .else mov x30, xzr .endif +.Lskip_tramp_vectors_cleanup\@: .endif -alternative_else_nop_endif -#endif sub sp, sp, #S_FRAME_SIZE b el\()\el\()_\label +.org .Lventry_start\@ + 128 // Did we overflow the ventry slot? .endm - .macro tramp_alias, dst, sym + .macro tramp_alias, dst, sym, tmp mov_q \dst, TRAMP_VALIAS - add \dst, \dst, #(\sym - .entry.tramp.text) + adr_l \tmp, \sym + add \dst, \dst, \tmp + adr_l \tmp, .entry.tramp.text + sub \dst, \dst, \tmp .endm // This macro corrupts x0-x3. It is the caller's duty @@ -238,21 +245,25 @@ alternative_else_nop_endif ldp x24, x25, [sp, #16 * 12] ldp x26, x27, [sp, #16 * 13] ldp x28, x29, [sp, #16 * 14] - ldr lr, [sp, #S_LR] - add sp, sp, #S_FRAME_SIZE // restore sp .if \el == 0 -alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0 +alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0 + ldr lr, [sp, #S_LR] + add sp, sp, #S_FRAME_SIZE // restore sp + eret +alternative_else_nop_endif #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 bne 4f - msr far_el1, x30 - tramp_alias x30, tramp_exit_native + msr far_el1, x29 + tramp_alias x30, tramp_exit_native, x29 br x30 4: - tramp_alias x30, tramp_exit_compat + tramp_alias x30, tramp_exit_compat, x29 br x30 #endif .else + ldr lr, [sp, #S_LR] + add sp, sp, #S_FRAME_SIZE // restore sp eret .endif .endm @@ -883,12 +894,7 @@ __ni_sys_trace: .popsection // .entry.text -#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 -/* - * Exception vectors trampoline. - */ - .pushsection ".entry.tramp.text", "ax" - + // Move from tramp_pg_dir to swapper_pg_dir .macro tramp_map_kernel, tmp mrs \tmp, ttbr1_el1 sub \tmp, \tmp, #SWAPPER_DIR_SIZE @@ -908,12 +914,47 @@ __ni_sys_trace: */ .endm - .macro tramp_ventry, regsize = 64 + .macro tramp_data_page dst + adr_l \dst, .entry.tramp.text + sub \dst, \dst, PAGE_SIZE + .endm + + .macro tramp_data_read_var dst, var +#ifdef CONFIG_RANDOMIZE_BASE + tramp_data_page \dst + add \dst, \dst, #:lo12:__entry_tramp_data_\var + ldr \dst, [\dst] +#else + ldr \dst, =\var +#endif + .endm + +#define BHB_MITIGATION_NONE 0 +#define BHB_MITIGATION_LOOP 1 +#define BHB_MITIGATION_FW 2 +#define BHB_MITIGATION_INSN 3 + + .macro tramp_ventry, vector_start, regsize, kpti, bhb .align 7 1: .if \regsize == 64 msr tpidrro_el0, x30 // Restored in kernel_ventry .endif + + .if \bhb == BHB_MITIGATION_LOOP + /* + * This sequence must appear before the first indirect branch. i.e. the + * ret out of tramp_ventry. It appears here because x30 is free. + */ + __mitigate_spectre_bhb_loop x30 + .endif // \bhb == BHB_MITIGATION_LOOP + + .if \bhb == BHB_MITIGATION_INSN + clearbhb + isb + .endif // \bhb == BHB_MITIGATION_INSN + + .if \kpti == 1 /* * Defend against branch aliasing attacks by pushing a dummy * entry onto the return stack and using a RET instruction to @@ -923,43 +964,74 @@ __ni_sys_trace: b . 2: tramp_map_kernel x30 -#ifdef CONFIG_RANDOMIZE_BASE - adr x30, tramp_vectors + PAGE_SIZE - isb - ldr x30, [x30] -#else - ldr x30, =vectors -#endif - prfm plil1strm, [x30, #(1b - tramp_vectors)] + tramp_data_read_var x30, vectors + prfm plil1strm, [x30, #(1b - \vector_start)] msr vbar_el1, x30 - add x30, x30, #(1b - tramp_vectors) isb + .else + ldr x30, =vectors + .endif // \kpti == 1 + + .if \bhb == BHB_MITIGATION_FW + /* + * The firmware sequence must appear before the first indirect branch. + * i.e. the ret out of tramp_ventry. But it also needs the stack to be + * mapped to save/restore the registers the SMC clobbers. + */ + __mitigate_spectre_bhb_fw + .endif // \bhb == BHB_MITIGATION_FW + + add x30, x30, #(1b - \vector_start + 4) ret +.org 1b + 128 // Did we overflow the ventry slot? .endm .macro tramp_exit, regsize = 64 - adr x30, tramp_vectors + tramp_data_read_var x30, this_cpu_vector +alternative_if_not ARM64_HAS_VIRT_HOST_EXTN + mrs x29, tpidr_el1 +alternative_else + mrs x29, tpidr_el2 +alternative_endif + ldr x30, [x30, x29] + msr vbar_el1, x30 - tramp_unmap_kernel x30 + ldr lr, [sp, #S_LR] + tramp_unmap_kernel x29 .if \regsize == 64 - mrs x30, far_el1 + mrs x29, far_el1 .endif + add sp, sp, #S_FRAME_SIZE // restore sp eret .endm - .align 11 -ENTRY(tramp_vectors) + .macro generate_tramp_vector, kpti, bhb +.Lvector_start\@: .space 0x400 - tramp_ventry - tramp_ventry - tramp_ventry - tramp_ventry + .rept 4 + tramp_ventry .Lvector_start\@, 64, \kpti, \bhb + .endr + .rept 4 + tramp_ventry .Lvector_start\@, 32, \kpti, \bhb + .endr + .endm - tramp_ventry 32 - tramp_ventry 32 - tramp_ventry 32 - tramp_ventry 32 +#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 +/* + * Exception vectors trampoline. + * The order must match __bp_harden_el1_vectors and the + * arm64_bp_harden_el1_vectors enum. + */ + .pushsection ".entry.tramp.text", "ax" + .align 11 +ENTRY(tramp_vectors) +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY + generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_LOOP + generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_FW + generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_INSN +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ + generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_NONE END(tramp_vectors) ENTRY(tramp_exit_native) @@ -977,11 +1049,54 @@ END(tramp_exit_compat) .align PAGE_SHIFT .globl __entry_tramp_data_start __entry_tramp_data_start: +__entry_tramp_data_vectors: .quad vectors +#ifdef CONFIG_ARM_SDE_INTERFACE +__entry_tramp_data___sdei_asm_trampoline_next_handler: + .quad __sdei_asm_handler +#endif /* CONFIG_ARM_SDE_INTERFACE */ +__entry_tramp_data_this_cpu_vector: + .quad this_cpu_vector .popsection // .rodata #endif /* CONFIG_RANDOMIZE_BASE */ #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */ +/* + * Exception vectors for spectre mitigations on entry from EL1 when + * kpti is not in use. + */ + .macro generate_el1_vector, bhb +.Lvector_start\@: + kernel_ventry 1, sync_invalid // Synchronous EL1t + kernel_ventry 1, irq_invalid // IRQ EL1t + kernel_ventry 1, fiq_invalid // FIQ EL1t + kernel_ventry 1, error_invalid // Error EL1t + + kernel_ventry 1, sync // Synchronous EL1h + kernel_ventry 1, irq // IRQ EL1h + kernel_ventry 1, fiq_invalid // FIQ EL1h + kernel_ventry 1, error_invalid // Error EL1h + + .rept 4 + tramp_ventry .Lvector_start\@, 64, 0, \bhb + .endr + .rept 4 + tramp_ventry .Lvector_start\@, 32, 0, \bhb + .endr + .endm + +/* The order must match tramp_vecs and the arm64_bp_harden_el1_vectors enum. */ + .pushsection ".entry.text", "ax" + .align 11 +ENTRY(__bp_harden_el1_vectors) +#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY + generate_el1_vector bhb=BHB_MITIGATION_LOOP + generate_el1_vector bhb=BHB_MITIGATION_FW + generate_el1_vector bhb=BHB_MITIGATION_INSN +#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */ +END(__bp_harden_el1_vectors) + .popsection + /* * Special system call wrappers. */ diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 1d5890f19ca32..ee34be8bed03a 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -26,6 +26,7 @@ #include #include +#include #include #define FPEXC_IOF (1 << 0) diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index 6f2ac4fc66ca2..755b3dd3073e5 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -418,6 +418,35 @@ u32 __kprobes aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type, return insn; } +u32 aarch64_insn_decode_register(enum aarch64_insn_register_type type, + u32 insn) +{ + int shift; + + switch (type) { + case AARCH64_INSN_REGTYPE_RT: + case AARCH64_INSN_REGTYPE_RD: + shift = 0; + break; + case AARCH64_INSN_REGTYPE_RN: + shift = 5; + break; + case AARCH64_INSN_REGTYPE_RT2: + case AARCH64_INSN_REGTYPE_RA: + shift = 10; + break; + case AARCH64_INSN_REGTYPE_RM: + shift = 16; + break; + default: + pr_err("%s: unknown register type encoding %d\n", __func__, + type); + return 0; + } + + return (insn >> shift) & GENMASK(4, 0); +} + static u32 aarch64_insn_encode_register(enum aarch64_insn_register_type type, u32 insn, enum aarch64_insn_register reg) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 13b9c20a84b5c..ea4aedb6bbdca 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -444,12 +444,6 @@ void __init smp_prepare_boot_cpu(void) jump_label_init(); cpuinfo_store_boot_cpu(); save_boot_cpu_run_el(); - /* - * Run the errata work around checks on the boot CPU, once we have - * initialised the cpu feature infrastructure from - * cpuinfo_store_boot_cpu() above. - */ - update_cpu_errata_workarounds(); } static u64 __init of_get_cpu_mpidr(struct device_node *dn) diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index b6fd2a21b015e..adf18b9a2c033 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -34,6 +34,7 @@ #include #include +#include #include #include #include @@ -432,10 +433,9 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs) force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0); } -int cpu_enable_cache_maint_trap(void *__unused) +void cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused) { config_sctlr_el1(SCTLR_EL1_UCI, 0); - return 0; } #define __user_cache_maint(insn, address, res) \ diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index fa3ffad50a61c..17fc1671b9900 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -261,7 +261,7 @@ ASSERT(__hibernate_exit_text_end - (__hibernate_exit_text_start & ~(SZ_4K - 1)) <= SZ_4K, "Hibernate exit text too big or misaligned") #endif #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 -ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) == PAGE_SIZE, +ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) <= 3*PAGE_SIZE, "Entry trampoline text too big") #endif /* diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index 7ced1fb93d077..d14a8c89d08e0 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -136,6 +136,10 @@ el1_hvc_guest: /* ARM_SMCCC_ARCH_WORKAROUND_2 handling */ eor w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_1 ^ \ ARM_SMCCC_ARCH_WORKAROUND_2) + cbz w1, wa_epilogue + + eor w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_2 ^ \ + ARM_SMCCC_ARCH_WORKAROUND_3) cbnz w1, el1_trap #ifdef CONFIG_ARM64_SSBD diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 0a2f37bceab0a..1751d2763cc12 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -26,7 +26,7 @@ #include #include #include - +#include extern struct exception_table_entry __start___kvm_ex_table; extern struct exception_table_entry __stop___kvm_ex_table; @@ -107,11 +107,14 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) static void __hyp_text __deactivate_traps_vhe(void) { - extern char vectors[]; /* kernel exception vectors */ + const char *host_vectors = vectors; write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); write_sysreg(CPACR_EL1_FPEN, cpacr_el1); - write_sysreg(vectors, vbar_el1); + + if (!arm64_kernel_unmapped_at_el0()) + host_vectors = __this_cpu_read(this_cpu_vector); + write_sysreg(host_vectors, vbar_el1); } static void __hyp_text __deactivate_traps_nvhe(void) diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index f3d3f2e97adde..a0c3efbc3717e 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -727,7 +727,7 @@ asmlinkage int __exception do_debug_exception(unsigned long addr_if_watchpoint, NOKPROBE_SYMBOL(do_debug_exception); #ifdef CONFIG_ARM64_PAN -int cpu_enable_pan(void *__unused) +void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused) { /* * We modify PSTATE. This won't work from irq context as the PSTATE @@ -737,20 +737,5 @@ int cpu_enable_pan(void *__unused) config_sctlr_el1(SCTLR_EL1_SPAN, 0); asm(SET_PSTATE_PAN(1)); - return 0; } #endif /* CONFIG_ARM64_PAN */ - -#ifdef CONFIG_ARM64_UAO -/* - * Kernel threads have fs=KERNEL_DS by default, and don't need to call - * set_fs(), devtmpfs in particular relies on this behaviour. - * We need to enable the feature at runtime (instead of adding it to - * PSR_MODE_EL1h) as the feature may not be implemented by the cpu. - */ -int cpu_enable_uao(void *__unused) -{ - asm(SET_PSTATE_UAO(1)); - return 0; -} -#endif /* CONFIG_ARM64_UAO */ diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 60be5bc0984ad..36bd50091c4bb 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -438,6 +438,7 @@ static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end, #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 static int __init map_entry_trampoline(void) { + int i; extern char __entry_tramp_text_start[]; pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; @@ -448,11 +449,15 @@ static int __init map_entry_trampoline(void) /* Map only the text into the trampoline page table */ memset(tramp_pg_dir, 0, PGD_SIZE); - __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE, - prot, pgd_pgtable_alloc, 0); + __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, + entry_tramp_text_size(), prot, pgd_pgtable_alloc, + 0); /* Map both the text and data into the kernel page table */ - __set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot); + for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++) + __set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i, + pa_start + i * PAGE_SIZE, prot); + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { extern char __entry_tramp_data_start[]; diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index e2c6e43cf8ca3..3d748eac1a688 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -305,10 +305,14 @@ config ARM_ARCH_TIMER_EVTSTREAM This must be disabled for hardware validation purposes to detect any hardware anomalies of missing events. +config ARM_ARCH_TIMER_OOL_WORKAROUND + bool + config FSL_ERRATUM_A008585 bool "Workaround for Freescale/NXP Erratum A-008585" default y depends on ARM_ARCH_TIMER && ARM64 + select ARM_ARCH_TIMER_OOL_WORKAROUND help This option enables a workaround for Freescale/NXP Erratum A-008585 ("ARM generic timer may contain an erroneous diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 5d7f83d27093f..e70d0974470c7 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -96,41 +96,159 @@ early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg); */ #ifdef CONFIG_FSL_ERRATUM_A008585 +/* + * The number of retries is an arbitrary value well beyond the highest number + * of iterations the loop has been observed to take. + */ +#define __fsl_a008585_read_reg(reg) ({ \ + u64 _old, _new; \ + int _retries = 200; \ + \ + do { \ + _old = read_sysreg(reg); \ + _new = read_sysreg(reg); \ + _retries--; \ + } while (unlikely(_old != _new) && _retries); \ + \ + WARN_ON_ONCE(!_retries); \ + _new; \ +}) + +static u32 notrace fsl_a008585_read_cntp_tval_el0(void) +{ + return __fsl_a008585_read_reg(cntp_tval_el0); +} + +static u32 notrace fsl_a008585_read_cntv_tval_el0(void) +{ + return __fsl_a008585_read_reg(cntv_tval_el0); +} + +static u64 notrace fsl_a008585_read_cntvct_el0(void) +{ + return __fsl_a008585_read_reg(cntvct_el0); +} +#endif + +#ifdef CONFIG_ARM64_ERRATUM_1188873 +static u64 notrace arm64_1188873_read_cntvct_el0(void) +{ + return read_sysreg(cntvct_el0); +} +#endif + +#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND +const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround = NULL; +EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround); + DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled); EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled); -static int fsl_a008585_enable = -1; +static const struct arch_timer_erratum_workaround ool_workarounds[] = { +#ifdef CONFIG_FSL_ERRATUM_A008585 + { + .match_type = ate_match_dt, + .id = "fsl,erratum-a008585", + .desc = "Freescale erratum a005858", + .read_cntp_tval_el0 = fsl_a008585_read_cntp_tval_el0, + .read_cntv_tval_el0 = fsl_a008585_read_cntv_tval_el0, + .read_cntvct_el0 = fsl_a008585_read_cntvct_el0, + }, +#endif +#ifdef CONFIG_ARM64_ERRATUM_1188873 + { + .match_type = ate_match_local_cap_id, + .id = (void *)ARM64_WORKAROUND_1188873, + .desc = "ARM erratum 1188873", + .read_cntvct_el0 = arm64_1188873_read_cntvct_el0, + }, +#endif +}; -static int __init early_fsl_a008585_cfg(char *buf) +typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *, + const void *); + +static +bool arch_timer_check_dt_erratum(const struct arch_timer_erratum_workaround *wa, + const void *arg) { - int ret; - bool val; + const struct device_node *np = arg; - ret = strtobool(buf, &val); - if (ret) - return ret; + return of_property_read_bool(np, wa->id); +} - fsl_a008585_enable = val; - return 0; +static +bool arch_timer_check_local_cap_erratum(const struct arch_timer_erratum_workaround *wa, + const void *arg) +{ + return this_cpu_has_cap((uintptr_t)wa->id); } -early_param("clocksource.arm_arch_timer.fsl-a008585", early_fsl_a008585_cfg); -u32 __fsl_a008585_read_cntp_tval_el0(void) +static const struct arch_timer_erratum_workaround * +arch_timer_iterate_errata(enum arch_timer_erratum_match_type type, + ate_match_fn_t match_fn, + void *arg) { - return __fsl_a008585_read_reg(cntp_tval_el0); + int i; + + for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) { + if (ool_workarounds[i].match_type != type) + continue; + + if (match_fn(&ool_workarounds[i], arg)) + return &ool_workarounds[i]; + } + + return NULL; } -u32 __fsl_a008585_read_cntv_tval_el0(void) +static +void arch_timer_enable_workaround(const struct arch_timer_erratum_workaround *wa) { - return __fsl_a008585_read_reg(cntv_tval_el0); + timer_unstable_counter_workaround = wa; + static_branch_enable(&arch_timer_read_ool_enabled); } -u64 __fsl_a008585_read_cntvct_el0(void) +static void arch_timer_check_ool_workaround(enum arch_timer_erratum_match_type type, + void *arg) { - return __fsl_a008585_read_reg(cntvct_el0); + const struct arch_timer_erratum_workaround *wa; + ate_match_fn_t match_fn = NULL; + bool local = false; + + switch (type) { + case ate_match_dt: + match_fn = arch_timer_check_dt_erratum; + break; + case ate_match_local_cap_id: + match_fn = arch_timer_check_local_cap_erratum; + local = true; + break; + default: + WARN_ON(1); + return; + } + + wa = arch_timer_iterate_errata(type, match_fn, arg); + if (!wa) + return; + + if (needs_unstable_timer_counter_workaround()) { + if (wa != timer_unstable_counter_workaround) + pr_warn("Can't enable workaround for %s (clashes with %s\n)", + wa->desc, + timer_unstable_counter_workaround->desc); + return; + } + + arch_timer_enable_workaround(wa); + pr_info("Enabling %s workaround for %s\n", + local ? "local" : "global", wa->desc); } -EXPORT_SYMBOL(__fsl_a008585_read_cntvct_el0); -#endif /* CONFIG_FSL_ERRATUM_A008585 */ + +#else +#define arch_timer_check_ool_workaround(t,a) do { } while(0) +#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */ static __always_inline void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val, @@ -281,8 +399,8 @@ static __always_inline void set_next_event(const int access, unsigned long evt, arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk); } -#ifdef CONFIG_FSL_ERRATUM_A008585 -static __always_inline void fsl_a008585_set_next_event(const int access, +#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND +static __always_inline void erratum_set_next_event_generic(const int access, unsigned long evt, struct clock_event_device *clk) { unsigned long ctrl; @@ -300,20 +418,20 @@ static __always_inline void fsl_a008585_set_next_event(const int access, arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk); } -static int fsl_a008585_set_next_event_virt(unsigned long evt, +static int erratum_set_next_event_virt(unsigned long evt, struct clock_event_device *clk) { - fsl_a008585_set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk); + erratum_set_next_event_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk); return 0; } -static int fsl_a008585_set_next_event_phys(unsigned long evt, +static int erratum_set_next_event_phys(unsigned long evt, struct clock_event_device *clk) { - fsl_a008585_set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk); + erratum_set_next_event_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk); return 0; } -#endif /* CONFIG_FSL_ERRATUM_A008585 */ +#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */ static int arch_timer_set_next_event_virt(unsigned long evt, struct clock_event_device *clk) @@ -343,16 +461,16 @@ static int arch_timer_set_next_event_phys_mem(unsigned long evt, return 0; } -static void fsl_a008585_set_sne(struct clock_event_device *clk) +static void erratum_workaround_set_sne(struct clock_event_device *clk) { -#ifdef CONFIG_FSL_ERRATUM_A008585 +#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND if (!static_branch_unlikely(&arch_timer_read_ool_enabled)) return; if (arch_timer_uses_ppi == VIRT_PPI) - clk->set_next_event = fsl_a008585_set_next_event_virt; + clk->set_next_event = erratum_set_next_event_virt; else - clk->set_next_event = fsl_a008585_set_next_event_phys; + clk->set_next_event = erratum_set_next_event_phys; #endif } @@ -385,7 +503,9 @@ static void __arch_timer_setup(unsigned type, BUG(); } - fsl_a008585_set_sne(clk); + arch_timer_check_ool_workaround(ate_match_local_cap_id, NULL); + + erratum_workaround_set_sne(clk); } else { clk->features |= CLOCK_EVT_FEAT_DYNIRQ; clk->name = "arch_mem_timer"; @@ -614,7 +734,7 @@ static void __init arch_counter_register(unsigned type) clocksource_counter.archdata.vdso_direct = true; -#ifdef CONFIG_FSL_ERRATUM_A008585 +#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND /* * Don't use the vdso fastpath if errata require using * the out-of-line counter accessor. @@ -902,14 +1022,8 @@ static int __init arch_timer_of_init(struct device_node *np) arch_timer_c3stop = !of_property_read_bool(np, "always-on"); -#ifdef CONFIG_FSL_ERRATUM_A008585 - if (fsl_a008585_enable < 0) - fsl_a008585_enable = of_property_read_bool(np, "fsl,erratum-a008585"); - if (fsl_a008585_enable) { - static_branch_enable(&arch_timer_read_ool_enabled); - pr_info("Enabling workaround for FSL erratum A-008585\n"); - } -#endif + /* Check for globally applicable workarounds */ + arch_timer_check_ool_workaround(ate_match_dt, np); /* * If we cannot rely on firmware initializing the timer registers then diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index 6366b04c7d5f4..0402668914147 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -85,6 +85,13 @@ ARM_SMCCC_SMC_32, \ 0, 0x7fff) +#define ARM_SMCCC_ARCH_WORKAROUND_3 \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + 0, 0x3fff) + +#define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED 1 + #ifndef __ASSEMBLY__ #include