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-rw-r--r--arch/x86/kernel/cpu/aperfmperf.c480
-rw-r--r--arch/x86/kernel/cpu/bugs.c7
-rw-r--r--arch/x86/kernel/cpu/common.c105
-rw-r--r--arch/x86/kernel/cpu/intel.c78
-rw-r--r--arch/x86/kernel/cpu/mce/amd.c32
-rw-r--r--arch/x86/kernel/cpu/mce/core.c4
-rw-r--r--arch/x86/kernel/cpu/mce/severity.c110
-rw-r--r--arch/x86/kernel/cpu/proc.c11
-rw-r--r--arch/x86/kernel/cpu/resctrl/rdtgroup.c14
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;