diff options
Diffstat (limited to 'arch/x86/kernel/cpu')
-rw-r--r-- | arch/x86/kernel/cpu/aperfmperf.c | 480 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 7 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/common.c | 105 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/intel.c | 78 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/mce/amd.c | 32 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/mce/core.c | 4 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/mce/severity.c | 110 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/proc.c | 11 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/resctrl/rdtgroup.c | 14 |
9 files changed, 586 insertions, 255 deletions
diff --git a/arch/x86/kernel/cpu/aperfmperf.c b/arch/x86/kernel/cpu/aperfmperf.c index 9ca008f9e9b1..1f60a2b27936 100644 --- a/arch/x86/kernel/cpu/aperfmperf.c +++ b/arch/x86/kernel/cpu/aperfmperf.c @@ -6,146 +6,446 @@ * Copyright (C) 2017 Intel Corp. * Author: Len Brown <len.brown@intel.com> */ - +#include <linux/cpufreq.h> #include <linux/delay.h> #include <linux/ktime.h> #include <linux/math64.h> #include <linux/percpu.h> -#include <linux/cpufreq.h> -#include <linux/smp.h> -#include <linux/sched/isolation.h> #include <linux/rcupdate.h> +#include <linux/sched/isolation.h> +#include <linux/sched/topology.h> +#include <linux/smp.h> +#include <linux/syscore_ops.h> + +#include <asm/cpu.h> +#include <asm/cpu_device_id.h> +#include <asm/intel-family.h> #include "cpu.h" -struct aperfmperf_sample { - unsigned int khz; - atomic_t scfpending; - ktime_t time; - u64 aperf; - u64 mperf; +struct aperfmperf { + seqcount_t seq; + unsigned long last_update; + u64 acnt; + u64 mcnt; + u64 aperf; + u64 mperf; }; -static DEFINE_PER_CPU(struct aperfmperf_sample, samples); +static DEFINE_PER_CPU_SHARED_ALIGNED(struct aperfmperf, cpu_samples) = { + .seq = SEQCNT_ZERO(cpu_samples.seq) +}; -#define APERFMPERF_CACHE_THRESHOLD_MS 10 -#define APERFMPERF_REFRESH_DELAY_MS 10 -#define APERFMPERF_STALE_THRESHOLD_MS 1000 +static void init_counter_refs(void) +{ + u64 aperf, mperf; + + rdmsrl(MSR_IA32_APERF, aperf); + rdmsrl(MSR_IA32_MPERF, mperf); + this_cpu_write(cpu_samples.aperf, aperf); + this_cpu_write(cpu_samples.mperf, mperf); +} + +#if defined(CONFIG_X86_64) && defined(CONFIG_SMP) /* - * aperfmperf_snapshot_khz() - * On the current CPU, snapshot APERF, MPERF, and jiffies - * unless we already did it within 10ms - * calculate kHz, save snapshot + * APERF/MPERF frequency ratio computation. + * + * The scheduler wants to do frequency invariant accounting and needs a <1 + * ratio to account for the 'current' frequency, corresponding to + * freq_curr / freq_max. + * + * Since the frequency freq_curr on x86 is controlled by micro-controller and + * our P-state setting is little more than a request/hint, we need to observe + * the effective frequency 'BusyMHz', i.e. the average frequency over a time + * interval after discarding idle time. This is given by: + * + * BusyMHz = delta_APERF / delta_MPERF * freq_base + * + * where freq_base is the max non-turbo P-state. + * + * The freq_max term has to be set to a somewhat arbitrary value, because we + * can't know which turbo states will be available at a given point in time: + * it all depends on the thermal headroom of the entire package. We set it to + * the turbo level with 4 cores active. + * + * Benchmarks show that's a good compromise between the 1C turbo ratio + * (freq_curr/freq_max would rarely reach 1) and something close to freq_base, + * which would ignore the entire turbo range (a conspicuous part, making + * freq_curr/freq_max always maxed out). + * + * An exception to the heuristic above is the Atom uarch, where we choose the + * highest turbo level for freq_max since Atom's are generally oriented towards + * power efficiency. + * + * Setting freq_max to anything less than the 1C turbo ratio makes the ratio + * freq_curr / freq_max to eventually grow >1, in which case we clip it to 1. */ -static void aperfmperf_snapshot_khz(void *dummy) + +DEFINE_STATIC_KEY_FALSE(arch_scale_freq_key); + +static u64 arch_turbo_freq_ratio = SCHED_CAPACITY_SCALE; +static u64 arch_max_freq_ratio = SCHED_CAPACITY_SCALE; + +void arch_set_max_freq_ratio(bool turbo_disabled) { - u64 aperf, aperf_delta; - u64 mperf, mperf_delta; - struct aperfmperf_sample *s = this_cpu_ptr(&samples); - unsigned long flags; + arch_max_freq_ratio = turbo_disabled ? SCHED_CAPACITY_SCALE : + arch_turbo_freq_ratio; +} +EXPORT_SYMBOL_GPL(arch_set_max_freq_ratio); - local_irq_save(flags); - rdmsrl(MSR_IA32_APERF, aperf); - rdmsrl(MSR_IA32_MPERF, mperf); - local_irq_restore(flags); +static bool __init turbo_disabled(void) +{ + u64 misc_en; + int err; + + err = rdmsrl_safe(MSR_IA32_MISC_ENABLE, &misc_en); + if (err) + return false; + + return (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE); +} + +static bool __init slv_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq) +{ + int err; + + err = rdmsrl_safe(MSR_ATOM_CORE_RATIOS, base_freq); + if (err) + return false; + + err = rdmsrl_safe(MSR_ATOM_CORE_TURBO_RATIOS, turbo_freq); + if (err) + return false; + + *base_freq = (*base_freq >> 16) & 0x3F; /* max P state */ + *turbo_freq = *turbo_freq & 0x3F; /* 1C turbo */ + + return true; +} + +#define X86_MATCH(model) \ + X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, \ + INTEL_FAM6_##model, X86_FEATURE_APERFMPERF, NULL) + +static const struct x86_cpu_id has_knl_turbo_ratio_limits[] __initconst = { + X86_MATCH(XEON_PHI_KNL), + X86_MATCH(XEON_PHI_KNM), + {} +}; + +static const struct x86_cpu_id has_skx_turbo_ratio_limits[] __initconst = { + X86_MATCH(SKYLAKE_X), + {} +}; + +static const struct x86_cpu_id has_glm_turbo_ratio_limits[] __initconst = { + X86_MATCH(ATOM_GOLDMONT), + X86_MATCH(ATOM_GOLDMONT_D), + X86_MATCH(ATOM_GOLDMONT_PLUS), + {} +}; + +static bool __init knl_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, + int num_delta_fratio) +{ + int fratio, delta_fratio, found; + int err, i; + u64 msr; + + err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); + if (err) + return false; + + *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ + + err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr); + if (err) + return false; + + fratio = (msr >> 8) & 0xFF; + i = 16; + found = 0; + do { + if (found >= num_delta_fratio) { + *turbo_freq = fratio; + return true; + } + + delta_fratio = (msr >> (i + 5)) & 0x7; + + if (delta_fratio) { + found += 1; + fratio -= delta_fratio; + } + + i += 8; + } while (i < 64); + + return true; +} + +static bool __init skx_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, int size) +{ + u64 ratios, counts; + u32 group_size; + int err, i; + + err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); + if (err) + return false; + + *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ + + err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &ratios); + if (err) + return false; + + err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT1, &counts); + if (err) + return false; + + for (i = 0; i < 64; i += 8) { + group_size = (counts >> i) & 0xFF; + if (group_size >= size) { + *turbo_freq = (ratios >> i) & 0xFF; + return true; + } + } + + return false; +} - aperf_delta = aperf - s->aperf; - mperf_delta = mperf - s->mperf; +static bool __init core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq) +{ + u64 msr; + int err; + + err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq); + if (err) + return false; + + err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr); + if (err) + return false; + + *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */ + *turbo_freq = (msr >> 24) & 0xFF; /* 4C turbo */ + + /* The CPU may have less than 4 cores */ + if (!*turbo_freq) + *turbo_freq = msr & 0xFF; /* 1C turbo */ + + return true; +} + +static bool __init intel_set_max_freq_ratio(void) +{ + u64 base_freq, turbo_freq; + u64 turbo_ratio; + if (slv_set_max_freq_ratio(&base_freq, &turbo_freq)) + goto out; + + if (x86_match_cpu(has_glm_turbo_ratio_limits) && + skx_set_max_freq_ratio(&base_freq, &turbo_freq, 1)) + goto out; + + if (x86_match_cpu(has_knl_turbo_ratio_limits) && + knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1)) + goto out; + + if (x86_match_cpu(has_skx_turbo_ratio_limits) && + skx_set_max_freq_ratio(&base_freq, &turbo_freq, 4)) + goto out; + + if (core_set_max_freq_ratio(&base_freq, &turbo_freq)) + goto out; + + return false; + +out: /* - * There is no architectural guarantee that MPERF - * increments faster than we can read it. + * Some hypervisors advertise X86_FEATURE_APERFMPERF + * but then fill all MSR's with zeroes. + * Some CPUs have turbo boost but don't declare any turbo ratio + * in MSR_TURBO_RATIO_LIMIT. */ - if (mperf_delta == 0) - return; + if (!base_freq || !turbo_freq) { + pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting.\n"); + return false; + } - s->time = ktime_get(); - s->aperf = aperf; - s->mperf = mperf; - s->khz = div64_u64((cpu_khz * aperf_delta), mperf_delta); - atomic_set_release(&s->scfpending, 0); + turbo_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, base_freq); + if (!turbo_ratio) { + pr_debug("Non-zero turbo and base frequencies led to a 0 ratio.\n"); + return false; + } + + arch_turbo_freq_ratio = turbo_ratio; + arch_set_max_freq_ratio(turbo_disabled()); + + return true; } -static bool aperfmperf_snapshot_cpu(int cpu, ktime_t now, bool wait) +#ifdef CONFIG_PM_SLEEP +static struct syscore_ops freq_invariance_syscore_ops = { + .resume = init_counter_refs, +}; + +static void register_freq_invariance_syscore_ops(void) { - s64 time_delta = ktime_ms_delta(now, per_cpu(samples.time, cpu)); - struct aperfmperf_sample *s = per_cpu_ptr(&samples, cpu); + register_syscore_ops(&freq_invariance_syscore_ops); +} +#else +static inline void register_freq_invariance_syscore_ops(void) {} +#endif - /* Don't bother re-computing within the cache threshold time. */ - if (time_delta < APERFMPERF_CACHE_THRESHOLD_MS) - return true; +static void freq_invariance_enable(void) +{ + if (static_branch_unlikely(&arch_scale_freq_key)) { + WARN_ON_ONCE(1); + return; + } + static_branch_enable(&arch_scale_freq_key); + register_freq_invariance_syscore_ops(); + pr_info("Estimated ratio of average max frequency by base frequency (times 1024): %llu\n", arch_max_freq_ratio); +} + +void freq_invariance_set_perf_ratio(u64 ratio, bool turbo_disabled) +{ + arch_turbo_freq_ratio = ratio; + arch_set_max_freq_ratio(turbo_disabled); + freq_invariance_enable(); +} + +static void __init bp_init_freq_invariance(void) +{ + if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) + return; - if (!atomic_xchg(&s->scfpending, 1) || wait) - smp_call_function_single(cpu, aperfmperf_snapshot_khz, NULL, wait); + if (intel_set_max_freq_ratio()) + freq_invariance_enable(); +} - /* Return false if the previous iteration was too long ago. */ - return time_delta <= APERFMPERF_STALE_THRESHOLD_MS; +static void disable_freq_invariance_workfn(struct work_struct *work) +{ + static_branch_disable(&arch_scale_freq_key); } -unsigned int aperfmperf_get_khz(int cpu) +static DECLARE_WORK(disable_freq_invariance_work, + disable_freq_invariance_workfn); + +DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE; + +static void scale_freq_tick(u64 acnt, u64 mcnt) { - if (!cpu_khz) - return 0; + u64 freq_scale; - if (!boot_cpu_has(X86_FEATURE_APERFMPERF)) - return 0; + if (!arch_scale_freq_invariant()) + return; - if (!housekeeping_cpu(cpu, HK_TYPE_MISC)) - return 0; + if (check_shl_overflow(acnt, 2*SCHED_CAPACITY_SHIFT, &acnt)) + goto error; - if (rcu_is_idle_cpu(cpu)) - return 0; /* Idle CPUs are completely uninteresting. */ + if (check_mul_overflow(mcnt, arch_max_freq_ratio, &mcnt) || !mcnt) + goto error; - aperfmperf_snapshot_cpu(cpu, ktime_get(), true); - return per_cpu(samples.khz, cpu); + freq_scale = div64_u64(acnt, mcnt); + if (!freq_scale) + goto error; + + if (freq_scale > SCHED_CAPACITY_SCALE) + freq_scale = SCHED_CAPACITY_SCALE; + + this_cpu_write(arch_freq_scale, freq_scale); + return; + +error: + pr_warn("Scheduler frequency invariance went wobbly, disabling!\n"); + schedule_work(&disable_freq_invariance_work); } +#else +static inline void bp_init_freq_invariance(void) { } +static inline void scale_freq_tick(u64 acnt, u64 mcnt) { } +#endif /* CONFIG_X86_64 && CONFIG_SMP */ -void arch_freq_prepare_all(void) +void arch_scale_freq_tick(void) { - ktime_t now = ktime_get(); - bool wait = false; - int cpu; + struct aperfmperf *s = this_cpu_ptr(&cpu_samples); + u64 acnt, mcnt, aperf, mperf; - if (!cpu_khz) + if (!cpu_feature_enabled(X86_FEATURE_APERFMPERF)) return; - if (!boot_cpu_has(X86_FEATURE_APERFMPERF)) - return; + rdmsrl(MSR_IA32_APERF, aperf); + rdmsrl(MSR_IA32_MPERF, mperf); + acnt = aperf - s->aperf; + mcnt = mperf - s->mperf; - for_each_online_cpu(cpu) { - if (!housekeeping_cpu(cpu, HK_TYPE_MISC)) - continue; - if (rcu_is_idle_cpu(cpu)) - continue; /* Idle CPUs are completely uninteresting. */ - if (!aperfmperf_snapshot_cpu(cpu, now, false)) - wait = true; - } + s->aperf = aperf; + s->mperf = mperf; + + raw_write_seqcount_begin(&s->seq); + s->last_update = jiffies; + s->acnt = acnt; + s->mcnt = mcnt; + raw_write_seqcount_end(&s->seq); - if (wait) - msleep(APERFMPERF_REFRESH_DELAY_MS); + scale_freq_tick(acnt, mcnt); } +/* + * Discard samples older than the define maximum sample age of 20ms. There + * is no point in sending IPIs in such a case. If the scheduler tick was + * not running then the CPU is either idle or isolated. + */ +#define MAX_SAMPLE_AGE ((unsigned long)HZ / 50) + unsigned int arch_freq_get_on_cpu(int cpu) { - struct aperfmperf_sample *s = per_cpu_ptr(&samples, cpu); + struct aperfmperf *s = per_cpu_ptr(&cpu_samples, cpu); + unsigned int seq, freq; + unsigned long last; + u64 acnt, mcnt; - if (!cpu_khz) - return 0; + if (!cpu_feature_enabled(X86_FEATURE_APERFMPERF)) + goto fallback; - if (!boot_cpu_has(X86_FEATURE_APERFMPERF)) - return 0; + do { + seq = raw_read_seqcount_begin(&s->seq); + last = s->last_update; + acnt = s->acnt; + mcnt = s->mcnt; + } while (read_seqcount_retry(&s->seq, seq)); - if (!housekeeping_cpu(cpu, HK_TYPE_MISC)) - return 0; + /* + * Bail on invalid count and when the last update was too long ago, + * which covers idle and NOHZ full CPUs. + */ + if (!mcnt || (jiffies - last) > MAX_SAMPLE_AGE) + goto fallback; + + return div64_u64((cpu_khz * acnt), mcnt); + +fallback: + freq = cpufreq_quick_get(cpu); + return freq ? freq : cpu_khz; +} - if (aperfmperf_snapshot_cpu(cpu, ktime_get(), true)) - return per_cpu(samples.khz, cpu); +static int __init bp_init_aperfmperf(void) +{ + if (!cpu_feature_enabled(X86_FEATURE_APERFMPERF)) + return 0; - msleep(APERFMPERF_REFRESH_DELAY_MS); - atomic_set(&s->scfpending, 1); - smp_mb(); /* ->scfpending before smp_call_function_single(). */ - smp_call_function_single(cpu, aperfmperf_snapshot_khz, NULL, 1); + init_counter_refs(); + bp_init_freq_invariance(); + return 0; +} +early_initcall(bp_init_aperfmperf); - return per_cpu(samples.khz, cpu); +void ap_init_aperfmperf(void) +{ + if (cpu_feature_enabled(X86_FEATURE_APERFMPERF)) + init_counter_refs(); } diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 6296e1ebed1d..d879a6c93609 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -446,6 +446,13 @@ void update_srbds_msr(void) if (srbds_mitigation == SRBDS_MITIGATION_UCODE_NEEDED) return; + /* + * A MDS_NO CPU for which SRBDS mitigation is not needed due to TSX + * being disabled and it hasn't received the SRBDS MSR microcode. + */ + if (!boot_cpu_has(X86_FEATURE_SRBDS_CTRL)) + return; + rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl); switch (srbds_mitigation) { diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index e342ae4db3c4..2e9142797c99 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -60,6 +60,7 @@ #include <asm/uv/uv.h> #include <asm/sigframe.h> #include <asm/traps.h> +#include <asm/sev.h> #include "cpu.h" @@ -298,13 +299,6 @@ static int __init cachesize_setup(char *str) } __setup("cachesize=", cachesize_setup); -static int __init x86_sep_setup(char *s) -{ - setup_clear_cpu_cap(X86_FEATURE_SEP); - return 1; -} -__setup("nosep", x86_sep_setup); - /* Standard macro to see if a specific flag is changeable */ static inline int flag_is_changeable_p(u32 flag) { @@ -376,26 +370,12 @@ static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c) } #endif -static __init int setup_disable_smep(char *arg) -{ - setup_clear_cpu_cap(X86_FEATURE_SMEP); - return 1; -} -__setup("nosmep", setup_disable_smep); - static __always_inline void setup_smep(struct cpuinfo_x86 *c) { if (cpu_has(c, X86_FEATURE_SMEP)) cr4_set_bits(X86_CR4_SMEP); } -static __init int setup_disable_smap(char *arg) -{ - setup_clear_cpu_cap(X86_FEATURE_SMAP); - return 1; -} -__setup("nosmap", setup_disable_smap); - static __always_inline void setup_smap(struct cpuinfo_x86 *c) { unsigned long eflags = native_save_fl(); @@ -403,14 +383,8 @@ static __always_inline void setup_smap(struct cpuinfo_x86 *c) /* This should have been cleared long ago */ BUG_ON(eflags & X86_EFLAGS_AC); - if (cpu_has(c, X86_FEATURE_SMAP)) { -#ifdef CONFIG_X86_SMAP + if (cpu_has(c, X86_FEATURE_SMAP)) cr4_set_bits(X86_CR4_SMAP); -#else - clear_cpu_cap(c, X86_FEATURE_SMAP); - cr4_clear_bits(X86_CR4_SMAP); -#endif - } } static __always_inline void setup_umip(struct cpuinfo_x86 *c) @@ -1368,8 +1342,8 @@ static void detect_nopl(void) static void __init cpu_parse_early_param(void) { char arg[128]; - char *argptr = arg; - int arglen, res, bit; + char *argptr = arg, *opt; + int arglen, taint = 0; #ifdef CONFIG_X86_32 if (cmdline_find_option_bool(boot_command_line, "no387")) @@ -1397,21 +1371,61 @@ static void __init cpu_parse_early_param(void) return; pr_info("Clearing CPUID bits:"); - do { - res = get_option(&argptr, &bit); - if (res == 0 || res == 3) - break; - /* If the argument was too long, the last bit may be cut off */ - if (res == 1 && arglen >= sizeof(arg)) - break; + while (argptr) { + bool found __maybe_unused = false; + unsigned int bit; + + opt = strsep(&argptr, ","); + + /* + * Handle naked numbers first for feature flags which don't + * have names. + */ + if (!kstrtouint(opt, 10, &bit)) { + if (bit < NCAPINTS * 32) { + +#ifdef CONFIG_X86_FEATURE_NAMES + /* empty-string, i.e., ""-defined feature flags */ + if (!x86_cap_flags[bit]) + pr_cont(" " X86_CAP_FMT_NUM, x86_cap_flag_num(bit)); + else +#endif + pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit)); + + setup_clear_cpu_cap(bit); + taint++; + } + /* + * The assumption is that there are no feature names with only + * numbers in the name thus go to the next argument. + */ + continue; + } + +#ifdef CONFIG_X86_FEATURE_NAMES + for (bit = 0; bit < 32 * NCAPINTS; bit++) { + if (!x86_cap_flag(bit)) + continue; - if (bit >= 0 && bit < NCAPINTS * 32) { - pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit)); + if (strcmp(x86_cap_flag(bit), opt)) + continue; + + pr_cont(" %s", opt); setup_clear_cpu_cap(bit); + taint++; + found = true; + break; } - } while (res == 2); + + if (!found) + pr_cont(" (unknown: %s)", opt); +#endif + } pr_cont("\n"); + + if (taint) + add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK); } /* @@ -1859,14 +1873,6 @@ void identify_secondary_cpu(struct cpuinfo_x86 *c) tsx_ap_init(); } -static __init int setup_noclflush(char *arg) -{ - setup_clear_cpu_cap(X86_FEATURE_CLFLUSH); - setup_clear_cpu_cap(X86_FEATURE_CLFLUSHOPT); - return 1; -} -__setup("noclflush", setup_noclflush); - void print_cpu_info(struct cpuinfo_x86 *c) { const char *vendor = NULL; @@ -2126,6 +2132,9 @@ void cpu_init_exception_handling(void) load_TR_desc(); + /* GHCB needs to be setup to handle #VC. */ + setup_ghcb(); + /* Finally load the IDT */ load_current_idt(); } diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index f7a5370a9b3b..7860241a67db 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -7,10 +7,13 @@ #include <linux/smp.h> #include <linux/sched.h> #include <linux/sched/clock.h> +#include <linux/semaphore.h> #include <linux/thread_info.h> #include <linux/init.h> #include <linux/uaccess.h> +#include <linux/workqueue.h> #include <linux/delay.h> +#include <linux/cpuhotplug.h> #include <asm/cpufeature.h> #include <asm/msr.h> @@ -91,7 +94,7 @@ static bool ring3mwait_disabled __read_mostly; static int __init ring3mwait_disable(char *__unused) { ring3mwait_disabled = true; - return 0; + return 1; } __setup("ring3mwait=disable", ring3mwait_disable); @@ -999,6 +1002,8 @@ static const struct { static struct ratelimit_state bld_ratelimit; +static DEFINE_SEMAPHORE(buslock_sem); + static inline bool match_option(const char *arg, int arglen, const char *opt) { int len = strlen(opt), ratelimit; @@ -1109,18 +1114,52 @@ static void split_lock_init(void) split_lock_verify_msr(sld_state != sld_off); } +static void __split_lock_reenable(struct work_struct *work) +{ + sld_update_msr(true); + up(&buslock_sem); +} + +/* + * If a CPU goes offline with pending delayed work to re-enable split lock + * detection then the delayed work will be executed on some other CPU. That + * handles releasing the buslock_sem, but because it executes on a + * different CPU probably won't re-enable split lock detection. This is a + * problem on HT systems since the sibling CPU on the same core may then be + * left running with split lock detection disabled. + * + * Unconditionally re-enable detection here. + */ +static int splitlock_cpu_offline(unsigned int cpu) +{ + sld_update_msr(true); + + return 0; +} + +static DECLARE_DELAYED_WORK(split_lock_reenable, __split_lock_reenable); + static void split_lock_warn(unsigned long ip) { - pr_warn_ratelimited("#AC: %s/%d took a split_lock trap at address: 0x%lx\n", - current->comm, current->pid, ip); + int cpu; - /* - * Disable the split lock detection for this task so it can make - * progress and set TIF_SLD so the detection is re-enabled via - * switch_to_sld() when the task is scheduled out. - */ + if (!current->reported_split_lock) + pr_warn_ratelimited("#AC: %s/%d took a split_lock trap at address: 0x%lx\n", + current->comm, current->pid, ip); + current->reported_split_lock = 1; + + /* misery factor #1, sleep 10ms before trying to execute split lock */ + if (msleep_interruptible(10) > 0) + return; + /* Misery factor #2, only allow one buslocked disabled core at a time */ + if (down_interruptible(&buslock_sem) == -EINTR) + return; + cpu = get_cpu(); + schedule_delayed_work_on(cpu, &split_lock_reenable, 2); + + /* Disable split lock detection on this CPU to make progress */ sld_update_msr(false); - set_tsk_thread_flag(current, TIF_SLD); + put_cpu(); } bool handle_guest_split_lock(unsigned long ip) @@ -1194,18 +1233,6 @@ void handle_bus_lock(struct pt_regs *regs) } /* - * This function is called only when switching between tasks with - * different split-lock detection modes. It sets the MSR for the - * mode of the new task. This is right most of the time, but since - * the MSR is shared by hyperthreads on a physical core there can - * be glitches when the two threads need different modes. - */ -void switch_to_sld(unsigned long tifn) -{ - sld_update_msr(!(tifn & _TIF_SLD)); -} - -/* * Bits in the IA32_CORE_CAPABILITIES are not architectural, so they should * only be trusted if it is confirmed that a CPU model implements a * specific feature at a particular bit position. @@ -1230,6 +1257,7 @@ static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = { X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, 1), X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE, 1), X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L, 1), + X86_MATCH_INTEL_FAM6_MODEL(RAPTORLAKE, 1), {} }; @@ -1274,10 +1302,14 @@ static void sld_state_show(void) pr_info("disabled\n"); break; case sld_warn: - if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) + if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) { pr_info("#AC: crashing the kernel on kernel split_locks and warning on user-space split_locks\n"); - else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) + if (cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, + "x86/splitlock", NULL, splitlock_cpu_offline) < 0) + pr_warn("No splitlock CPU offline handler\n"); + } else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) { pr_info("#DB: warning on user-space bus_locks\n"); + } break; case sld_fatal: if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) { diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c index 1940d305db1c..1c87501e0fa3 100644 --- a/arch/x86/kernel/cpu/mce/amd.c +++ b/arch/x86/kernel/cpu/mce/amd.c @@ -1294,10 +1294,23 @@ out_free: kfree(bank); } +static void __threshold_remove_device(struct threshold_bank **bp) +{ + unsigned int bank, numbanks = this_cpu_read(mce_num_banks); + + for (bank = 0; bank < numbanks; bank++) { + if (!bp[bank]) + continue; + + threshold_remove_bank(bp[bank]); + bp[bank] = NULL; + } + kfree(bp); +} + int mce_threshold_remove_device(unsigned int cpu) { struct threshold_bank **bp = this_cpu_read(threshold_banks); - unsigned int bank, numbanks = this_cpu_read(mce_num_banks); if (!bp) return 0; @@ -1308,13 +1321,7 @@ int mce_threshold_remove_device(unsigned int cpu) */ this_cpu_write(threshold_banks, NULL); - for (bank = 0; bank < numbanks; bank++) { - if (bp[bank]) { - threshold_remove_bank(bp[bank]); - bp[bank] = NULL; - } - } - kfree(bp); + __threshold_remove_device(bp); return 0; } @@ -1351,15 +1358,14 @@ int mce_threshold_create_device(unsigned int cpu) if (!(this_cpu_read(bank_map) & (1 << bank))) continue; err = threshold_create_bank(bp, cpu, bank); - if (err) - goto out_err; + if (err) { + __threshold_remove_device(bp); + return err; + } } this_cpu_write(threshold_banks, bp); if (thresholding_irq_en) mce_threshold_vector = amd_threshold_interrupt; return 0; -out_err: - mce_threshold_remove_device(cpu); - return err; } diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 981496e6bc0e..d775fcd74e98 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -69,7 +69,9 @@ DEFINE_PER_CPU_READ_MOSTLY(unsigned int, mce_num_banks); struct mce_bank { u64 ctl; /* subevents to enable */ - bool init; /* initialise bank? */ + + __u64 init : 1, /* initialise bank? */ + __reserved_1 : 63; }; static DEFINE_PER_CPU_READ_MOSTLY(struct mce_bank[MAX_NR_BANKS], mce_banks_array); diff --git a/arch/x86/kernel/cpu/mce/severity.c b/arch/x86/kernel/cpu/mce/severity.c index 1add86935349..00483d1c27e4 100644 --- a/arch/x86/kernel/cpu/mce/severity.c +++ b/arch/x86/kernel/cpu/mce/severity.c @@ -301,85 +301,65 @@ static noinstr int error_context(struct mce *m, struct pt_regs *regs) } } -static __always_inline int mce_severity_amd_smca(struct mce *m, enum context err_ctx) +/* See AMD PPR(s) section Machine Check Error Handling. */ +static noinstr int mce_severity_amd(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp) { - u64 mcx_cfg; + char *panic_msg = NULL; + int ret; /* - * We need to look at the following bits: - * - "succor" bit (data poisoning support), and - * - TCC bit (Task Context Corrupt) - * in MCi_STATUS to determine error severity. + * Default return value: Action required, the error must be handled + * immediately. */ - if (!mce_flags.succor) - return MCE_PANIC_SEVERITY; - - mcx_cfg = mce_rdmsrl(MSR_AMD64_SMCA_MCx_CONFIG(m->bank)); - - /* TCC (Task context corrupt). If set and if IN_KERNEL, panic. */ - if ((mcx_cfg & MCI_CONFIG_MCAX) && - (m->status & MCI_STATUS_TCC) && - (err_ctx == IN_KERNEL)) - return MCE_PANIC_SEVERITY; - - /* ...otherwise invoke hwpoison handler. */ - return MCE_AR_SEVERITY; -} - -/* - * See AMD Error Scope Hierarchy table in a newer BKDG. For example - * 49125_15h_Models_30h-3Fh_BKDG.pdf, section "RAS Features" - */ -static noinstr int mce_severity_amd(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp) -{ - enum context ctx = error_context(m, regs); + ret = MCE_AR_SEVERITY; /* Processor Context Corrupt, no need to fumble too much, die! */ - if (m->status & MCI_STATUS_PCC) - return MCE_PANIC_SEVERITY; - - if (m->status & MCI_STATUS_UC) { - - if (ctx == IN_KERNEL) - return MCE_PANIC_SEVERITY; + if (m->status & MCI_STATUS_PCC) { + panic_msg = "Processor Context Corrupt"; + ret = MCE_PANIC_SEVERITY; + goto out; + } - /* - * On older systems where overflow_recov flag is not present, we - * should simply panic if an error overflow occurs. If - * overflow_recov flag is present and set, then software can try - * to at least kill process to prolong system operation. - */ - if (mce_flags.overflow_recov) { - if (mce_flags.smca) - return mce_severity_amd_smca(m, ctx); - - /* kill current process */ - return MCE_AR_SEVERITY; - } else { - /* at least one error was not logged */ - if (m->status & MCI_STATUS_OVER) - return MCE_PANIC_SEVERITY; - } - - /* - * For any other case, return MCE_UC_SEVERITY so that we log the - * error and exit #MC handler. - */ - return MCE_UC_SEVERITY; + if (m->status & MCI_STATUS_DEFERRED) { + ret = MCE_DEFERRED_SEVERITY; + goto out; } /* - * deferred error: poll handler catches these and adds to mce_ring so - * memory-failure can take recovery actions. + * If the UC bit is not set, the system either corrected or deferred + * the error. No action will be required after logging the error. */ - if (m->status & MCI_STATUS_DEFERRED) - return MCE_DEFERRED_SEVERITY; + if (!(m->status & MCI_STATUS_UC)) { + ret = MCE_KEEP_SEVERITY; + goto out; + } /* - * corrected error: poll handler catches these and passes responsibility - * of decoding the error to EDAC + * On MCA overflow, without the MCA overflow recovery feature the + * system will not be able to recover, panic. */ - return MCE_KEEP_SEVERITY; + if ((m->status & MCI_STATUS_OVER) && !mce_flags.overflow_recov) { + panic_msg = "Overflowed uncorrected error without MCA Overflow Recovery"; + ret = MCE_PANIC_SEVERITY; + goto out; + } + + if (!mce_flags.succor) { + panic_msg = "Uncorrected error without MCA Recovery"; + ret = MCE_PANIC_SEVERITY; + goto out; + } + + if (error_context(m, regs) == IN_KERNEL) { + panic_msg = "Uncorrected unrecoverable error in kernel context"; + ret = MCE_PANIC_SEVERITY; + } + +out: + if (msg && panic_msg) + *msg = panic_msg; + + return ret; } static noinstr int mce_severity_intel(struct mce *m, struct pt_regs *regs, char **msg, bool is_excp) diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c index 4eec8889b0ff..099b6f0d96bd 100644 --- a/arch/x86/kernel/cpu/proc.c +++ b/arch/x86/kernel/cpu/proc.c @@ -84,14 +84,9 @@ static int show_cpuinfo(struct seq_file *m, void *v) seq_printf(m, "microcode\t: 0x%x\n", c->microcode); if (cpu_has(c, X86_FEATURE_TSC)) { - unsigned int freq = aperfmperf_get_khz(cpu); - - if (!freq) - freq = cpufreq_quick_get(cpu); - if (!freq) - freq = cpu_khz; - seq_printf(m, "cpu MHz\t\t: %u.%03u\n", - freq / 1000, (freq % 1000)); + unsigned int freq = arch_freq_get_on_cpu(cpu); + + seq_printf(m, "cpu MHz\t\t: %u.%03u\n", freq / 1000, (freq % 1000)); } /* Cache size */ diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 83f901e2c2df..f276aff521e8 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -341,14 +341,14 @@ static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask, /* Check whether cpus belong to parent ctrl group */ cpumask_andnot(tmpmask, newmask, &prgrp->cpu_mask); - if (cpumask_weight(tmpmask)) { + if (!cpumask_empty(tmpmask)) { rdt_last_cmd_puts("Can only add CPUs to mongroup that belong to parent\n"); return -EINVAL; } /* Check whether cpus are dropped from this group */ cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask); - if (cpumask_weight(tmpmask)) { + if (!cpumask_empty(tmpmask)) { /* Give any dropped cpus to parent rdtgroup */ cpumask_or(&prgrp->cpu_mask, &prgrp->cpu_mask, tmpmask); update_closid_rmid(tmpmask, prgrp); @@ -359,7 +359,7 @@ static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask, * and update per-cpu rmid */ cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask); - if (cpumask_weight(tmpmask)) { + if (!cpumask_empty(tmpmask)) { head = &prgrp->mon.crdtgrp_list; list_for_each_entry(crgrp, head, mon.crdtgrp_list) { if (crgrp == rdtgrp) @@ -394,7 +394,7 @@ static int cpus_ctrl_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask, /* Check whether cpus are dropped from this group */ cpumask_andnot(tmpmask, &rdtgrp->cpu_mask, newmask); - if (cpumask_weight(tmpmask)) { + if (!cpumask_empty(tmpmask)) { /* Can't drop from default group */ if (rdtgrp == &rdtgroup_default) { rdt_last_cmd_puts("Can't drop CPUs from default group\n"); @@ -413,12 +413,12 @@ static int cpus_ctrl_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask, * and update per-cpu closid/rmid. */ cpumask_andnot(tmpmask, newmask, &rdtgrp->cpu_mask); - if (cpumask_weight(tmpmask)) { + if (!cpumask_empty(tmpmask)) { list_for_each_entry(r, &rdt_all_groups, rdtgroup_list) { if (r == rdtgrp) continue; cpumask_and(tmpmask1, &r->cpu_mask, tmpmask); - if (cpumask_weight(tmpmask1)) + if (!cpumask_empty(tmpmask1)) cpumask_rdtgrp_clear(r, tmpmask1); } update_closid_rmid(tmpmask, rdtgrp); @@ -488,7 +488,7 @@ static ssize_t rdtgroup_cpus_write(struct kernfs_open_file *of, /* check that user didn't specify any offline cpus */ cpumask_andnot(tmpmask, newmask, cpu_online_mask); - if (cpumask_weight(tmpmask)) { + if (!cpumask_empty(tmpmask)) { ret = -EINVAL; rdt_last_cmd_puts("Can only assign online CPUs\n"); goto unlock; |