diff options
Diffstat (limited to 'kernel/arch/x86/kernel/cpu/common.c')
-rw-r--r-- | kernel/arch/x86/kernel/cpu/common.c | 1514 |
1 files changed, 1514 insertions, 0 deletions
diff --git a/kernel/arch/x86/kernel/cpu/common.c b/kernel/arch/x86/kernel/cpu/common.c new file mode 100644 index 000000000..a62cf04da --- /dev/null +++ b/kernel/arch/x86/kernel/cpu/common.c @@ -0,0 +1,1514 @@ +#include <linux/bootmem.h> +#include <linux/linkage.h> +#include <linux/bitops.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/percpu.h> +#include <linux/string.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <linux/kprobes.h> +#include <linux/kgdb.h> +#include <linux/smp.h> +#include <linux/io.h> + +#include <asm/stackprotector.h> +#include <asm/perf_event.h> +#include <asm/mmu_context.h> +#include <asm/archrandom.h> +#include <asm/hypervisor.h> +#include <asm/processor.h> +#include <asm/tlbflush.h> +#include <asm/debugreg.h> +#include <asm/sections.h> +#include <asm/vsyscall.h> +#include <linux/topology.h> +#include <linux/cpumask.h> +#include <asm/pgtable.h> +#include <linux/atomic.h> +#include <asm/proto.h> +#include <asm/setup.h> +#include <asm/apic.h> +#include <asm/desc.h> +#include <asm/i387.h> +#include <asm/fpu-internal.h> +#include <asm/mtrr.h> +#include <linux/numa.h> +#include <asm/asm.h> +#include <asm/cpu.h> +#include <asm/mce.h> +#include <asm/msr.h> +#include <asm/pat.h> +#include <asm/microcode.h> +#include <asm/microcode_intel.h> + +#ifdef CONFIG_X86_LOCAL_APIC +#include <asm/uv/uv.h> +#endif + +#include "cpu.h" + +/* all of these masks are initialized in setup_cpu_local_masks() */ +cpumask_var_t cpu_initialized_mask; +cpumask_var_t cpu_callout_mask; +cpumask_var_t cpu_callin_mask; + +/* representing cpus for which sibling maps can be computed */ +cpumask_var_t cpu_sibling_setup_mask; + +/* correctly size the local cpu masks */ +void __init setup_cpu_local_masks(void) +{ + alloc_bootmem_cpumask_var(&cpu_initialized_mask); + alloc_bootmem_cpumask_var(&cpu_callin_mask); + alloc_bootmem_cpumask_var(&cpu_callout_mask); + alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask); +} + +static void default_init(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_X86_64 + cpu_detect_cache_sizes(c); +#else + /* Not much we can do here... */ + /* Check if at least it has cpuid */ + if (c->cpuid_level == -1) { + /* No cpuid. It must be an ancient CPU */ + if (c->x86 == 4) + strcpy(c->x86_model_id, "486"); + else if (c->x86 == 3) + strcpy(c->x86_model_id, "386"); + } +#endif +} + +static const struct cpu_dev default_cpu = { + .c_init = default_init, + .c_vendor = "Unknown", + .c_x86_vendor = X86_VENDOR_UNKNOWN, +}; + +static const struct cpu_dev *this_cpu = &default_cpu; + +DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = { +#ifdef CONFIG_X86_64 + /* + * We need valid kernel segments for data and code in long mode too + * IRET will check the segment types kkeil 2000/10/28 + * Also sysret mandates a special GDT layout + * + * TLS descriptors are currently at a different place compared to i386. + * Hopefully nobody expects them at a fixed place (Wine?) + */ + [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff), + [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff), + [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff), + [GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff), + [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff), + [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff), +#else + [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff), + [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff), + [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff), + [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff), + /* + * Segments used for calling PnP BIOS have byte granularity. + * They code segments and data segments have fixed 64k limits, + * the transfer segment sizes are set at run time. + */ + /* 32-bit code */ + [GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(0x409a, 0, 0xffff), + /* 16-bit code */ + [GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(0x009a, 0, 0xffff), + /* 16-bit data */ + [GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(0x0092, 0, 0xffff), + /* 16-bit data */ + [GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(0x0092, 0, 0), + /* 16-bit data */ + [GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(0x0092, 0, 0), + /* + * The APM segments have byte granularity and their bases + * are set at run time. All have 64k limits. + */ + /* 32-bit code */ + [GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(0x409a, 0, 0xffff), + /* 16-bit code */ + [GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff), + /* data */ + [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff), + + [GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff), + [GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff), + GDT_STACK_CANARY_INIT +#endif +} }; +EXPORT_PER_CPU_SYMBOL_GPL(gdt_page); + +static int __init x86_xsave_setup(char *s) +{ + if (strlen(s)) + return 0; + setup_clear_cpu_cap(X86_FEATURE_XSAVE); + setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); + setup_clear_cpu_cap(X86_FEATURE_XSAVES); + setup_clear_cpu_cap(X86_FEATURE_AVX); + setup_clear_cpu_cap(X86_FEATURE_AVX2); + return 1; +} +__setup("noxsave", x86_xsave_setup); + +static int __init x86_xsaveopt_setup(char *s) +{ + setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); + return 1; +} +__setup("noxsaveopt", x86_xsaveopt_setup); + +static int __init x86_xsaves_setup(char *s) +{ + setup_clear_cpu_cap(X86_FEATURE_XSAVES); + return 1; +} +__setup("noxsaves", x86_xsaves_setup); + +#ifdef CONFIG_X86_32 +static int cachesize_override = -1; +static int disable_x86_serial_nr = 1; + +static int __init cachesize_setup(char *str) +{ + get_option(&str, &cachesize_override); + return 1; +} +__setup("cachesize=", cachesize_setup); + +static int __init x86_fxsr_setup(char *s) +{ + setup_clear_cpu_cap(X86_FEATURE_FXSR); + setup_clear_cpu_cap(X86_FEATURE_XMM); + return 1; +} +__setup("nofxsr", x86_fxsr_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) +{ + u32 f1, f2; + + /* + * Cyrix and IDT cpus allow disabling of CPUID + * so the code below may return different results + * when it is executed before and after enabling + * the CPUID. Add "volatile" to not allow gcc to + * optimize the subsequent calls to this function. + */ + asm volatile ("pushfl \n\t" + "pushfl \n\t" + "popl %0 \n\t" + "movl %0, %1 \n\t" + "xorl %2, %0 \n\t" + "pushl %0 \n\t" + "popfl \n\t" + "pushfl \n\t" + "popl %0 \n\t" + "popfl \n\t" + + : "=&r" (f1), "=&r" (f2) + : "ir" (flag)); + + return ((f1^f2) & flag) != 0; +} + +/* Probe for the CPUID instruction */ +int have_cpuid_p(void) +{ + return flag_is_changeable_p(X86_EFLAGS_ID); +} + +static void squash_the_stupid_serial_number(struct cpuinfo_x86 *c) +{ + unsigned long lo, hi; + + if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr) + return; + + /* Disable processor serial number: */ + + rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi); + lo |= 0x200000; + wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi); + + printk(KERN_NOTICE "CPU serial number disabled.\n"); + clear_cpu_cap(c, X86_FEATURE_PN); + + /* Disabling the serial number may affect the cpuid level */ + c->cpuid_level = cpuid_eax(0); +} + +static int __init x86_serial_nr_setup(char *s) +{ + disable_x86_serial_nr = 0; + return 1; +} +__setup("serialnumber", x86_serial_nr_setup); +#else +static inline int flag_is_changeable_p(u32 flag) +{ + return 1; +} +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; + + /* This should have been cleared long ago */ + raw_local_save_flags(eflags); + BUG_ON(eflags & X86_EFLAGS_AC); + + if (cpu_has(c, X86_FEATURE_SMAP)) { +#ifdef CONFIG_X86_SMAP + cr4_set_bits(X86_CR4_SMAP); +#else + cr4_clear_bits(X86_CR4_SMAP); +#endif + } +} + +/* + * Some CPU features depend on higher CPUID levels, which may not always + * be available due to CPUID level capping or broken virtualization + * software. Add those features to this table to auto-disable them. + */ +struct cpuid_dependent_feature { + u32 feature; + u32 level; +}; + +static const struct cpuid_dependent_feature +cpuid_dependent_features[] = { + { X86_FEATURE_MWAIT, 0x00000005 }, + { X86_FEATURE_DCA, 0x00000009 }, + { X86_FEATURE_XSAVE, 0x0000000d }, + { 0, 0 } +}; + +static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn) +{ + const struct cpuid_dependent_feature *df; + + for (df = cpuid_dependent_features; df->feature; df++) { + + if (!cpu_has(c, df->feature)) + continue; + /* + * Note: cpuid_level is set to -1 if unavailable, but + * extended_extended_level is set to 0 if unavailable + * and the legitimate extended levels are all negative + * when signed; hence the weird messing around with + * signs here... + */ + if (!((s32)df->level < 0 ? + (u32)df->level > (u32)c->extended_cpuid_level : + (s32)df->level > (s32)c->cpuid_level)) + continue; + + clear_cpu_cap(c, df->feature); + if (!warn) + continue; + + printk(KERN_WARNING + "CPU: CPU feature " X86_CAP_FMT " disabled, no CPUID level 0x%x\n", + x86_cap_flag(df->feature), df->level); + } +} + +/* + * Naming convention should be: <Name> [(<Codename>)] + * This table only is used unless init_<vendor>() below doesn't set it; + * in particular, if CPUID levels 0x80000002..4 are supported, this + * isn't used + */ + +/* Look up CPU names by table lookup. */ +static const char *table_lookup_model(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_X86_32 + const struct legacy_cpu_model_info *info; + + if (c->x86_model >= 16) + return NULL; /* Range check */ + + if (!this_cpu) + return NULL; + + info = this_cpu->legacy_models; + + while (info->family) { + if (info->family == c->x86) + return info->model_names[c->x86_model]; + info++; + } +#endif + return NULL; /* Not found */ +} + +__u32 cpu_caps_cleared[NCAPINTS]; +__u32 cpu_caps_set[NCAPINTS]; + +void load_percpu_segment(int cpu) +{ +#ifdef CONFIG_X86_32 + loadsegment(fs, __KERNEL_PERCPU); +#else + loadsegment(gs, 0); + wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu)); +#endif + load_stack_canary_segment(); +} + +/* + * Current gdt points %fs at the "master" per-cpu area: after this, + * it's on the real one. + */ +void switch_to_new_gdt(int cpu) +{ + struct desc_ptr gdt_descr; + + gdt_descr.address = (long)get_cpu_gdt_table(cpu); + gdt_descr.size = GDT_SIZE - 1; + load_gdt(&gdt_descr); + /* Reload the per-cpu base */ + + load_percpu_segment(cpu); +} + +static const struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {}; + +static void get_model_name(struct cpuinfo_x86 *c) +{ + unsigned int *v; + char *p, *q; + + if (c->extended_cpuid_level < 0x80000004) + return; + + v = (unsigned int *)c->x86_model_id; + cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]); + cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]); + cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]); + c->x86_model_id[48] = 0; + + /* + * Intel chips right-justify this string for some dumb reason; + * undo that brain damage: + */ + p = q = &c->x86_model_id[0]; + while (*p == ' ') + p++; + if (p != q) { + while (*p) + *q++ = *p++; + while (q <= &c->x86_model_id[48]) + *q++ = '\0'; /* Zero-pad the rest */ + } +} + +void cpu_detect_cache_sizes(struct cpuinfo_x86 *c) +{ + unsigned int n, dummy, ebx, ecx, edx, l2size; + + n = c->extended_cpuid_level; + + if (n >= 0x80000005) { + cpuid(0x80000005, &dummy, &ebx, &ecx, &edx); + c->x86_cache_size = (ecx>>24) + (edx>>24); +#ifdef CONFIG_X86_64 + /* On K8 L1 TLB is inclusive, so don't count it */ + c->x86_tlbsize = 0; +#endif + } + + if (n < 0x80000006) /* Some chips just has a large L1. */ + return; + + cpuid(0x80000006, &dummy, &ebx, &ecx, &edx); + l2size = ecx >> 16; + +#ifdef CONFIG_X86_64 + c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff); +#else + /* do processor-specific cache resizing */ + if (this_cpu->legacy_cache_size) + l2size = this_cpu->legacy_cache_size(c, l2size); + + /* Allow user to override all this if necessary. */ + if (cachesize_override != -1) + l2size = cachesize_override; + + if (l2size == 0) + return; /* Again, no L2 cache is possible */ +#endif + + c->x86_cache_size = l2size; +} + +u16 __read_mostly tlb_lli_4k[NR_INFO]; +u16 __read_mostly tlb_lli_2m[NR_INFO]; +u16 __read_mostly tlb_lli_4m[NR_INFO]; +u16 __read_mostly tlb_lld_4k[NR_INFO]; +u16 __read_mostly tlb_lld_2m[NR_INFO]; +u16 __read_mostly tlb_lld_4m[NR_INFO]; +u16 __read_mostly tlb_lld_1g[NR_INFO]; + +static void cpu_detect_tlb(struct cpuinfo_x86 *c) +{ + if (this_cpu->c_detect_tlb) + this_cpu->c_detect_tlb(c); + + pr_info("Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n", + tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES], + tlb_lli_4m[ENTRIES]); + + pr_info("Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d, 1GB %d\n", + tlb_lld_4k[ENTRIES], tlb_lld_2m[ENTRIES], + tlb_lld_4m[ENTRIES], tlb_lld_1g[ENTRIES]); +} + +void detect_ht(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_X86_HT + u32 eax, ebx, ecx, edx; + int index_msb, core_bits; + static bool printed; + + if (!cpu_has(c, X86_FEATURE_HT)) + return; + + if (cpu_has(c, X86_FEATURE_CMP_LEGACY)) + goto out; + + if (cpu_has(c, X86_FEATURE_XTOPOLOGY)) + return; + + cpuid(1, &eax, &ebx, &ecx, &edx); + + smp_num_siblings = (ebx & 0xff0000) >> 16; + + if (smp_num_siblings == 1) { + printk_once(KERN_INFO "CPU0: Hyper-Threading is disabled\n"); + goto out; + } + + if (smp_num_siblings <= 1) + goto out; + + index_msb = get_count_order(smp_num_siblings); + c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb); + + smp_num_siblings = smp_num_siblings / c->x86_max_cores; + + index_msb = get_count_order(smp_num_siblings); + + core_bits = get_count_order(c->x86_max_cores); + + c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) & + ((1 << core_bits) - 1); + +out: + if (!printed && (c->x86_max_cores * smp_num_siblings) > 1) { + printk(KERN_INFO "CPU: Physical Processor ID: %d\n", + c->phys_proc_id); + printk(KERN_INFO "CPU: Processor Core ID: %d\n", + c->cpu_core_id); + printed = 1; + } +#endif +} + +static void get_cpu_vendor(struct cpuinfo_x86 *c) +{ + char *v = c->x86_vendor_id; + int i; + + for (i = 0; i < X86_VENDOR_NUM; i++) { + if (!cpu_devs[i]) + break; + + if (!strcmp(v, cpu_devs[i]->c_ident[0]) || + (cpu_devs[i]->c_ident[1] && + !strcmp(v, cpu_devs[i]->c_ident[1]))) { + + this_cpu = cpu_devs[i]; + c->x86_vendor = this_cpu->c_x86_vendor; + return; + } + } + + printk_once(KERN_ERR + "CPU: vendor_id '%s' unknown, using generic init.\n" \ + "CPU: Your system may be unstable.\n", v); + + c->x86_vendor = X86_VENDOR_UNKNOWN; + this_cpu = &default_cpu; +} + +void cpu_detect(struct cpuinfo_x86 *c) +{ + /* Get vendor name */ + cpuid(0x00000000, (unsigned int *)&c->cpuid_level, + (unsigned int *)&c->x86_vendor_id[0], + (unsigned int *)&c->x86_vendor_id[8], + (unsigned int *)&c->x86_vendor_id[4]); + + c->x86 = 4; + /* Intel-defined flags: level 0x00000001 */ + if (c->cpuid_level >= 0x00000001) { + u32 junk, tfms, cap0, misc; + + cpuid(0x00000001, &tfms, &misc, &junk, &cap0); + c->x86 = (tfms >> 8) & 0xf; + c->x86_model = (tfms >> 4) & 0xf; + c->x86_mask = tfms & 0xf; + + if (c->x86 == 0xf) + c->x86 += (tfms >> 20) & 0xff; + if (c->x86 >= 0x6) + c->x86_model += ((tfms >> 16) & 0xf) << 4; + + if (cap0 & (1<<19)) { + c->x86_clflush_size = ((misc >> 8) & 0xff) * 8; + c->x86_cache_alignment = c->x86_clflush_size; + } + } +} + +void get_cpu_cap(struct cpuinfo_x86 *c) +{ + u32 tfms, xlvl; + u32 ebx; + + /* Intel-defined flags: level 0x00000001 */ + if (c->cpuid_level >= 0x00000001) { + u32 capability, excap; + + cpuid(0x00000001, &tfms, &ebx, &excap, &capability); + c->x86_capability[0] = capability; + c->x86_capability[4] = excap; + } + + /* Additional Intel-defined flags: level 0x00000007 */ + if (c->cpuid_level >= 0x00000007) { + u32 eax, ebx, ecx, edx; + + cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx); + + c->x86_capability[9] = ebx; + } + + /* Extended state features: level 0x0000000d */ + if (c->cpuid_level >= 0x0000000d) { + u32 eax, ebx, ecx, edx; + + cpuid_count(0x0000000d, 1, &eax, &ebx, &ecx, &edx); + + c->x86_capability[10] = eax; + } + + /* Additional Intel-defined flags: level 0x0000000F */ + if (c->cpuid_level >= 0x0000000F) { + u32 eax, ebx, ecx, edx; + + /* QoS sub-leaf, EAX=0Fh, ECX=0 */ + cpuid_count(0x0000000F, 0, &eax, &ebx, &ecx, &edx); + c->x86_capability[11] = edx; + if (cpu_has(c, X86_FEATURE_CQM_LLC)) { + /* will be overridden if occupancy monitoring exists */ + c->x86_cache_max_rmid = ebx; + + /* QoS sub-leaf, EAX=0Fh, ECX=1 */ + cpuid_count(0x0000000F, 1, &eax, &ebx, &ecx, &edx); + c->x86_capability[12] = edx; + if (cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC)) { + c->x86_cache_max_rmid = ecx; + c->x86_cache_occ_scale = ebx; + } + } else { + c->x86_cache_max_rmid = -1; + c->x86_cache_occ_scale = -1; + } + } + + /* AMD-defined flags: level 0x80000001 */ + xlvl = cpuid_eax(0x80000000); + c->extended_cpuid_level = xlvl; + + if ((xlvl & 0xffff0000) == 0x80000000) { + if (xlvl >= 0x80000001) { + c->x86_capability[1] = cpuid_edx(0x80000001); + c->x86_capability[6] = cpuid_ecx(0x80000001); + } + } + + if (c->extended_cpuid_level >= 0x80000008) { + u32 eax = cpuid_eax(0x80000008); + + c->x86_virt_bits = (eax >> 8) & 0xff; + c->x86_phys_bits = eax & 0xff; + } +#ifdef CONFIG_X86_32 + else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36)) + c->x86_phys_bits = 36; +#endif + + if (c->extended_cpuid_level >= 0x80000007) + c->x86_power = cpuid_edx(0x80000007); + + init_scattered_cpuid_features(c); +} + +static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_X86_32 + int i; + + /* + * First of all, decide if this is a 486 or higher + * It's a 486 if we can modify the AC flag + */ + if (flag_is_changeable_p(X86_EFLAGS_AC)) + c->x86 = 4; + else + c->x86 = 3; + + for (i = 0; i < X86_VENDOR_NUM; i++) + if (cpu_devs[i] && cpu_devs[i]->c_identify) { + c->x86_vendor_id[0] = 0; + cpu_devs[i]->c_identify(c); + if (c->x86_vendor_id[0]) { + get_cpu_vendor(c); + break; + } + } +#endif +} + +/* + * Do minimum CPU detection early. + * Fields really needed: vendor, cpuid_level, family, model, mask, + * cache alignment. + * The others are not touched to avoid unwanted side effects. + * + * WARNING: this function is only called on the BP. Don't add code here + * that is supposed to run on all CPUs. + */ +static void __init early_identify_cpu(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_X86_64 + c->x86_clflush_size = 64; + c->x86_phys_bits = 36; + c->x86_virt_bits = 48; +#else + c->x86_clflush_size = 32; + c->x86_phys_bits = 32; + c->x86_virt_bits = 32; +#endif + c->x86_cache_alignment = c->x86_clflush_size; + + memset(&c->x86_capability, 0, sizeof c->x86_capability); + c->extended_cpuid_level = 0; + + if (!have_cpuid_p()) + identify_cpu_without_cpuid(c); + + /* cyrix could have cpuid enabled via c_identify()*/ + if (!have_cpuid_p()) + return; + + cpu_detect(c); + get_cpu_vendor(c); + get_cpu_cap(c); + fpu_detect(c); + + if (this_cpu->c_early_init) + this_cpu->c_early_init(c); + + c->cpu_index = 0; + filter_cpuid_features(c, false); + + if (this_cpu->c_bsp_init) + this_cpu->c_bsp_init(c); + + setup_force_cpu_cap(X86_FEATURE_ALWAYS); +} + +void __init early_cpu_init(void) +{ + const struct cpu_dev *const *cdev; + int count = 0; + +#ifdef CONFIG_PROCESSOR_SELECT + printk(KERN_INFO "KERNEL supported cpus:\n"); +#endif + + for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) { + const struct cpu_dev *cpudev = *cdev; + + if (count >= X86_VENDOR_NUM) + break; + cpu_devs[count] = cpudev; + count++; + +#ifdef CONFIG_PROCESSOR_SELECT + { + unsigned int j; + + for (j = 0; j < 2; j++) { + if (!cpudev->c_ident[j]) + continue; + printk(KERN_INFO " %s %s\n", cpudev->c_vendor, + cpudev->c_ident[j]); + } + } +#endif + } + early_identify_cpu(&boot_cpu_data); +} + +/* + * The NOPL instruction is supposed to exist on all CPUs of family >= 6; + * unfortunately, that's not true in practice because of early VIA + * chips and (more importantly) broken virtualizers that are not easy + * to detect. In the latter case it doesn't even *fail* reliably, so + * probing for it doesn't even work. Disable it completely on 32-bit + * unless we can find a reliable way to detect all the broken cases. + * Enable it explicitly on 64-bit for non-constant inputs of cpu_has(). + */ +static void detect_nopl(struct cpuinfo_x86 *c) +{ +#ifdef CONFIG_X86_32 + clear_cpu_cap(c, X86_FEATURE_NOPL); +#else + set_cpu_cap(c, X86_FEATURE_NOPL); +#endif +} + +static void generic_identify(struct cpuinfo_x86 *c) +{ + c->extended_cpuid_level = 0; + + if (!have_cpuid_p()) + identify_cpu_without_cpuid(c); + + /* cyrix could have cpuid enabled via c_identify()*/ + if (!have_cpuid_p()) + return; + + cpu_detect(c); + + get_cpu_vendor(c); + + get_cpu_cap(c); + + if (c->cpuid_level >= 0x00000001) { + c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF; +#ifdef CONFIG_X86_32 +# ifdef CONFIG_X86_HT + c->apicid = apic->phys_pkg_id(c->initial_apicid, 0); +# else + c->apicid = c->initial_apicid; +# endif +#endif + c->phys_proc_id = c->initial_apicid; + } + + get_model_name(c); /* Default name */ + + detect_nopl(c); +} + +static void x86_init_cache_qos(struct cpuinfo_x86 *c) +{ + /* + * The heavy lifting of max_rmid and cache_occ_scale are handled + * in get_cpu_cap(). Here we just set the max_rmid for the boot_cpu + * in case CQM bits really aren't there in this CPU. + */ + if (c != &boot_cpu_data) { + boot_cpu_data.x86_cache_max_rmid = + min(boot_cpu_data.x86_cache_max_rmid, + c->x86_cache_max_rmid); + } +} + +/* + * This does the hard work of actually picking apart the CPU stuff... + */ +static void identify_cpu(struct cpuinfo_x86 *c) +{ + int i; + + c->loops_per_jiffy = loops_per_jiffy; + c->x86_cache_size = -1; + c->x86_vendor = X86_VENDOR_UNKNOWN; + c->x86_model = c->x86_mask = 0; /* So far unknown... */ + c->x86_vendor_id[0] = '\0'; /* Unset */ + c->x86_model_id[0] = '\0'; /* Unset */ + c->x86_max_cores = 1; + c->x86_coreid_bits = 0; +#ifdef CONFIG_X86_64 + c->x86_clflush_size = 64; + c->x86_phys_bits = 36; + c->x86_virt_bits = 48; +#else + c->cpuid_level = -1; /* CPUID not detected */ + c->x86_clflush_size = 32; + c->x86_phys_bits = 32; + c->x86_virt_bits = 32; +#endif + c->x86_cache_alignment = c->x86_clflush_size; + memset(&c->x86_capability, 0, sizeof c->x86_capability); + + generic_identify(c); + + if (this_cpu->c_identify) + this_cpu->c_identify(c); + + /* Clear/Set all flags overriden by options, after probe */ + for (i = 0; i < NCAPINTS; i++) { + c->x86_capability[i] &= ~cpu_caps_cleared[i]; + c->x86_capability[i] |= cpu_caps_set[i]; + } + +#ifdef CONFIG_X86_64 + c->apicid = apic->phys_pkg_id(c->initial_apicid, 0); +#endif + + /* + * Vendor-specific initialization. In this section we + * canonicalize the feature flags, meaning if there are + * features a certain CPU supports which CPUID doesn't + * tell us, CPUID claiming incorrect flags, or other bugs, + * we handle them here. + * + * At the end of this section, c->x86_capability better + * indicate the features this CPU genuinely supports! + */ + if (this_cpu->c_init) + this_cpu->c_init(c); + + /* Disable the PN if appropriate */ + squash_the_stupid_serial_number(c); + + /* Set up SMEP/SMAP */ + setup_smep(c); + setup_smap(c); + + /* + * The vendor-specific functions might have changed features. + * Now we do "generic changes." + */ + + /* Filter out anything that depends on CPUID levels we don't have */ + filter_cpuid_features(c, true); + + /* If the model name is still unset, do table lookup. */ + if (!c->x86_model_id[0]) { + const char *p; + p = table_lookup_model(c); + if (p) + strcpy(c->x86_model_id, p); + else + /* Last resort... */ + sprintf(c->x86_model_id, "%02x/%02x", + c->x86, c->x86_model); + } + +#ifdef CONFIG_X86_64 + detect_ht(c); +#endif + + init_hypervisor(c); + x86_init_rdrand(c); + x86_init_cache_qos(c); + + /* + * Clear/Set all flags overriden by options, need do it + * before following smp all cpus cap AND. + */ + for (i = 0; i < NCAPINTS; i++) { + c->x86_capability[i] &= ~cpu_caps_cleared[i]; + c->x86_capability[i] |= cpu_caps_set[i]; + } + + /* + * On SMP, boot_cpu_data holds the common feature set between + * all CPUs; so make sure that we indicate which features are + * common between the CPUs. The first time this routine gets + * executed, c == &boot_cpu_data. + */ + if (c != &boot_cpu_data) { + /* AND the already accumulated flags with these */ + for (i = 0; i < NCAPINTS; i++) + boot_cpu_data.x86_capability[i] &= c->x86_capability[i]; + + /* OR, i.e. replicate the bug flags */ + for (i = NCAPINTS; i < NCAPINTS + NBUGINTS; i++) + c->x86_capability[i] |= boot_cpu_data.x86_capability[i]; + } + + /* Init Machine Check Exception if available. */ + mcheck_cpu_init(c); + + select_idle_routine(c); + +#ifdef CONFIG_NUMA + numa_add_cpu(smp_processor_id()); +#endif +} + +/* + * Set up the CPU state needed to execute SYSENTER/SYSEXIT instructions + * on 32-bit kernels: + */ +#ifdef CONFIG_X86_32 +void enable_sep_cpu(void) +{ + struct tss_struct *tss; + int cpu; + + cpu = get_cpu(); + tss = &per_cpu(cpu_tss, cpu); + + if (!boot_cpu_has(X86_FEATURE_SEP)) + goto out; + + /* + * We cache MSR_IA32_SYSENTER_CS's value in the TSS's ss1 field -- + * see the big comment in struct x86_hw_tss's definition. + */ + + tss->x86_tss.ss1 = __KERNEL_CS; + wrmsr(MSR_IA32_SYSENTER_CS, tss->x86_tss.ss1, 0); + + wrmsr(MSR_IA32_SYSENTER_ESP, + (unsigned long)tss + offsetofend(struct tss_struct, SYSENTER_stack), + 0); + + wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)ia32_sysenter_target, 0); + +out: + put_cpu(); +} +#endif + +void __init identify_boot_cpu(void) +{ + identify_cpu(&boot_cpu_data); + init_amd_e400_c1e_mask(); +#ifdef CONFIG_X86_32 + sysenter_setup(); + enable_sep_cpu(); +#endif + cpu_detect_tlb(&boot_cpu_data); +} + +void identify_secondary_cpu(struct cpuinfo_x86 *c) +{ + BUG_ON(c == &boot_cpu_data); + identify_cpu(c); +#ifdef CONFIG_X86_32 + enable_sep_cpu(); +#endif + mtrr_ap_init(); +} + +struct msr_range { + unsigned min; + unsigned max; +}; + +static const struct msr_range msr_range_array[] = { + { 0x00000000, 0x00000418}, + { 0xc0000000, 0xc000040b}, + { 0xc0010000, 0xc0010142}, + { 0xc0011000, 0xc001103b}, +}; + +static void __print_cpu_msr(void) +{ + unsigned index_min, index_max; + unsigned index; + u64 val; + int i; + + for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) { + index_min = msr_range_array[i].min; + index_max = msr_range_array[i].max; + + for (index = index_min; index < index_max; index++) { + if (rdmsrl_safe(index, &val)) + continue; + printk(KERN_INFO " MSR%08x: %016llx\n", index, val); + } + } +} + +static int show_msr; + +static __init int setup_show_msr(char *arg) +{ + int num; + + get_option(&arg, &num); + + if (num > 0) + show_msr = num; + return 1; +} +__setup("show_msr=", setup_show_msr); + +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; + + if (c->x86_vendor < X86_VENDOR_NUM) { + vendor = this_cpu->c_vendor; + } else { + if (c->cpuid_level >= 0) + vendor = c->x86_vendor_id; + } + + if (vendor && !strstr(c->x86_model_id, vendor)) + printk(KERN_CONT "%s ", vendor); + + if (c->x86_model_id[0]) + printk(KERN_CONT "%s", strim(c->x86_model_id)); + else + printk(KERN_CONT "%d86", c->x86); + + printk(KERN_CONT " (fam: %02x, model: %02x", c->x86, c->x86_model); + + if (c->x86_mask || c->cpuid_level >= 0) + printk(KERN_CONT ", stepping: %02x)\n", c->x86_mask); + else + printk(KERN_CONT ")\n"); + + print_cpu_msr(c); +} + +void print_cpu_msr(struct cpuinfo_x86 *c) +{ + if (c->cpu_index < show_msr) + __print_cpu_msr(); +} + +static __init int setup_disablecpuid(char *arg) +{ + int bit; + + if (get_option(&arg, &bit) && bit < NCAPINTS*32) + setup_clear_cpu_cap(bit); + else + return 0; + + return 1; +} +__setup("clearcpuid=", setup_disablecpuid); + +DEFINE_PER_CPU(unsigned long, kernel_stack) = + (unsigned long)&init_thread_union + THREAD_SIZE; +EXPORT_PER_CPU_SYMBOL(kernel_stack); + +#ifdef CONFIG_X86_64 +struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table }; +struct desc_ptr debug_idt_descr = { NR_VECTORS * 16 - 1, + (unsigned long) debug_idt_table }; + +DEFINE_PER_CPU_FIRST(union irq_stack_union, + irq_stack_union) __aligned(PAGE_SIZE) __visible; + +/* + * The following percpu variables are hot. Align current_task to + * cacheline size such that they fall in the same cacheline. + */ +DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned = + &init_task; +EXPORT_PER_CPU_SYMBOL(current_task); + +DEFINE_PER_CPU(char *, irq_stack_ptr) = + init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64; + +DEFINE_PER_CPU(unsigned int, irq_count) __visible = -1; + +DEFINE_PER_CPU(int, __preempt_count) = INIT_PREEMPT_COUNT; +EXPORT_PER_CPU_SYMBOL(__preempt_count); + +DEFINE_PER_CPU(struct task_struct *, fpu_owner_task); + +/* + * Special IST stacks which the CPU switches to when it calls + * an IST-marked descriptor entry. Up to 7 stacks (hardware + * limit), all of them are 4K, except the debug stack which + * is 8K. + */ +static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = { + [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ, + [DEBUG_STACK - 1] = DEBUG_STKSZ +}; + +static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks + [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]); + +/* May not be marked __init: used by software suspend */ +void syscall_init(void) +{ + /* + * LSTAR and STAR live in a bit strange symbiosis. + * They both write to the same internal register. STAR allows to + * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip. + */ + wrmsrl(MSR_STAR, ((u64)__USER32_CS)<<48 | ((u64)__KERNEL_CS)<<32); + wrmsrl(MSR_LSTAR, system_call); + +#ifdef CONFIG_IA32_EMULATION + wrmsrl(MSR_CSTAR, ia32_cstar_target); + /* + * This only works on Intel CPUs. + * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP. + * This does not cause SYSENTER to jump to the wrong location, because + * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit). + */ + wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS); + wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL); + wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target); +#else + wrmsrl(MSR_CSTAR, ignore_sysret); + wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG); + wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL); + wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL); +#endif + + /* Flags to clear on syscall */ + wrmsrl(MSR_SYSCALL_MASK, + X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF| + X86_EFLAGS_IOPL|X86_EFLAGS_AC|X86_EFLAGS_NT); +} + +/* + * Copies of the original ist values from the tss are only accessed during + * debugging, no special alignment required. + */ +DEFINE_PER_CPU(struct orig_ist, orig_ist); + +static DEFINE_PER_CPU(unsigned long, debug_stack_addr); +DEFINE_PER_CPU(int, debug_stack_usage); + +int is_debug_stack(unsigned long addr) +{ + return __this_cpu_read(debug_stack_usage) || + (addr <= __this_cpu_read(debug_stack_addr) && + addr > (__this_cpu_read(debug_stack_addr) - DEBUG_STKSZ)); +} +NOKPROBE_SYMBOL(is_debug_stack); + +DEFINE_PER_CPU(u32, debug_idt_ctr); + +void debug_stack_set_zero(void) +{ + this_cpu_inc(debug_idt_ctr); + load_current_idt(); +} +NOKPROBE_SYMBOL(debug_stack_set_zero); + +void debug_stack_reset(void) +{ + if (WARN_ON(!this_cpu_read(debug_idt_ctr))) + return; + if (this_cpu_dec_return(debug_idt_ctr) == 0) + load_current_idt(); +} +NOKPROBE_SYMBOL(debug_stack_reset); + +#else /* CONFIG_X86_64 */ + +DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task; +EXPORT_PER_CPU_SYMBOL(current_task); +DEFINE_PER_CPU(int, __preempt_count) = INIT_PREEMPT_COUNT; +EXPORT_PER_CPU_SYMBOL(__preempt_count); +DEFINE_PER_CPU(struct task_struct *, fpu_owner_task); + +/* + * On x86_32, vm86 modifies tss.sp0, so sp0 isn't a reliable way to find + * the top of the kernel stack. Use an extra percpu variable to track the + * top of the kernel stack directly. + */ +DEFINE_PER_CPU(unsigned long, cpu_current_top_of_stack) = + (unsigned long)&init_thread_union + THREAD_SIZE; +EXPORT_PER_CPU_SYMBOL(cpu_current_top_of_stack); + +#ifdef CONFIG_CC_STACKPROTECTOR +DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary); +#endif + +#endif /* CONFIG_X86_64 */ + +/* + * Clear all 6 debug registers: + */ +static void clear_all_debug_regs(void) +{ + int i; + + for (i = 0; i < 8; i++) { + /* Ignore db4, db5 */ + if ((i == 4) || (i == 5)) + continue; + + set_debugreg(0, i); + } +} + +#ifdef CONFIG_KGDB +/* + * Restore debug regs if using kgdbwait and you have a kernel debugger + * connection established. + */ +static void dbg_restore_debug_regs(void) +{ + if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break)) + arch_kgdb_ops.correct_hw_break(); +} +#else /* ! CONFIG_KGDB */ +#define dbg_restore_debug_regs() +#endif /* ! CONFIG_KGDB */ + +static void wait_for_master_cpu(int cpu) +{ +#ifdef CONFIG_SMP + /* + * wait for ACK from master CPU before continuing + * with AP initialization + */ + WARN_ON(cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)); + while (!cpumask_test_cpu(cpu, cpu_callout_mask)) + cpu_relax(); +#endif +} + +/* + * cpu_init() initializes state that is per-CPU. Some data is already + * initialized (naturally) in the bootstrap process, such as the GDT + * and IDT. We reload them nevertheless, this function acts as a + * 'CPU state barrier', nothing should get across. + * A lot of state is already set up in PDA init for 64 bit + */ +#ifdef CONFIG_X86_64 + +void cpu_init(void) +{ + struct orig_ist *oist; + struct task_struct *me; + struct tss_struct *t; + unsigned long v; + int cpu = stack_smp_processor_id(); + int i; + + wait_for_master_cpu(cpu); + + /* + * Initialize the CR4 shadow before doing anything that could + * try to read it. + */ + cr4_init_shadow(); + + /* + * Load microcode on this cpu if a valid microcode is available. + * This is early microcode loading procedure. + */ + load_ucode_ap(); + + t = &per_cpu(cpu_tss, cpu); + oist = &per_cpu(orig_ist, cpu); + +#ifdef CONFIG_NUMA + if (this_cpu_read(numa_node) == 0 && + early_cpu_to_node(cpu) != NUMA_NO_NODE) + set_numa_node(early_cpu_to_node(cpu)); +#endif + + me = current; + + pr_debug("Initializing CPU#%d\n", cpu); + + cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE); + + /* + * Initialize the per-CPU GDT with the boot GDT, + * and set up the GDT descriptor: + */ + + switch_to_new_gdt(cpu); + loadsegment(fs, 0); + + load_current_idt(); + + memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8); + syscall_init(); + + wrmsrl(MSR_FS_BASE, 0); + wrmsrl(MSR_KERNEL_GS_BASE, 0); + barrier(); + + x86_configure_nx(); + x2apic_setup(); + + /* + * set up and load the per-CPU TSS + */ + if (!oist->ist[0]) { + char *estacks = per_cpu(exception_stacks, cpu); + + for (v = 0; v < N_EXCEPTION_STACKS; v++) { + estacks += exception_stack_sizes[v]; + oist->ist[v] = t->x86_tss.ist[v] = + (unsigned long)estacks; + if (v == DEBUG_STACK-1) + per_cpu(debug_stack_addr, cpu) = (unsigned long)estacks; + } + } + + t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap); + + /* + * <= is required because the CPU will access up to + * 8 bits beyond the end of the IO permission bitmap. + */ + for (i = 0; i <= IO_BITMAP_LONGS; i++) + t->io_bitmap[i] = ~0UL; + + atomic_inc(&init_mm.mm_count); + me->active_mm = &init_mm; + BUG_ON(me->mm); + enter_lazy_tlb(&init_mm, me); + + load_sp0(t, ¤t->thread); + set_tss_desc(cpu, t); + load_TR_desc(); + load_LDT(&init_mm.context); + + clear_all_debug_regs(); + dbg_restore_debug_regs(); + + fpu_init(); + + if (is_uv_system()) + uv_cpu_init(); +} + +#else + +void cpu_init(void) +{ + int cpu = smp_processor_id(); + struct task_struct *curr = current; + struct tss_struct *t = &per_cpu(cpu_tss, cpu); + struct thread_struct *thread = &curr->thread; + + wait_for_master_cpu(cpu); + + /* + * Initialize the CR4 shadow before doing anything that could + * try to read it. + */ + cr4_init_shadow(); + + show_ucode_info_early(); + + printk(KERN_INFO "Initializing CPU#%d\n", cpu); + + if (cpu_feature_enabled(X86_FEATURE_VME) || cpu_has_tsc || cpu_has_de) + cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE); + + load_current_idt(); + switch_to_new_gdt(cpu); + + /* + * Set up and load the per-CPU TSS and LDT + */ + atomic_inc(&init_mm.mm_count); + curr->active_mm = &init_mm; + BUG_ON(curr->mm); + enter_lazy_tlb(&init_mm, curr); + + load_sp0(t, thread); + set_tss_desc(cpu, t); + load_TR_desc(); + load_LDT(&init_mm.context); + + t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap); + +#ifdef CONFIG_DOUBLEFAULT + /* Set up doublefault TSS pointer in the GDT */ + __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss); +#endif + + clear_all_debug_regs(); + dbg_restore_debug_regs(); + + fpu_init(); +} +#endif + +#ifdef CONFIG_X86_DEBUG_STATIC_CPU_HAS +void warn_pre_alternatives(void) +{ + WARN(1, "You're using static_cpu_has before alternatives have run!\n"); +} +EXPORT_SYMBOL_GPL(warn_pre_alternatives); +#endif + +inline bool __static_cpu_has_safe(u16 bit) +{ + return boot_cpu_has(bit); +} +EXPORT_SYMBOL_GPL(__static_cpu_has_safe); |