Version:  2.6.32 2.6.33 2.6.34 2.6.35 2.6.36 2.6.37 2.6.38 2.6.39 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9

Architecture:  x86 arm avr32 blackfin m68k m68knommu microblaze mips powerpc sh

Linux/arch/x86/kernel/cpu/common.c

  1 #include <linux/bootmem.h>
  2 #include <linux/linkage.h>
  3 #include <linux/bitops.h>
  4 #include <linux/kernel.h>
  5 #include <linux/module.h>
  6 #include <linux/percpu.h>
  7 #include <linux/string.h>
  8 #include <linux/delay.h>
  9 #include <linux/sched.h>
 10 #include <linux/init.h>
 11 #include <linux/kgdb.h>
 12 #include <linux/smp.h>
 13 #include <linux/io.h>
 14 
 15 #include <asm/stackprotector.h>
 16 #include <asm/perf_event.h>
 17 #include <asm/mmu_context.h>
 18 #include <asm/archrandom.h>
 19 #include <asm/hypervisor.h>
 20 #include <asm/processor.h>
 21 #include <asm/debugreg.h>
 22 #include <asm/sections.h>
 23 #include <linux/topology.h>
 24 #include <linux/cpumask.h>
 25 #include <asm/pgtable.h>
 26 #include <linux/atomic.h>
 27 #include <asm/proto.h>
 28 #include <asm/setup.h>
 29 #include <asm/apic.h>
 30 #include <asm/desc.h>
 31 #include <asm/i387.h>
 32 #include <asm/fpu-internal.h>
 33 #include <asm/mtrr.h>
 34 #include <linux/numa.h>
 35 #include <asm/asm.h>
 36 #include <asm/cpu.h>
 37 #include <asm/mce.h>
 38 #include <asm/msr.h>
 39 #include <asm/pat.h>
 40 #include <asm/microcode.h>
 41 #include <asm/microcode_intel.h>
 42 
 43 #ifdef CONFIG_X86_LOCAL_APIC
 44 #include <asm/uv/uv.h>
 45 #endif
 46 
 47 #include "cpu.h"
 48 
 49 /* all of these masks are initialized in setup_cpu_local_masks() */
 50 cpumask_var_t cpu_initialized_mask;
 51 cpumask_var_t cpu_callout_mask;
 52 cpumask_var_t cpu_callin_mask;
 53 
 54 /* representing cpus for which sibling maps can be computed */
 55 cpumask_var_t cpu_sibling_setup_mask;
 56 
 57 /* correctly size the local cpu masks */
 58 void __init setup_cpu_local_masks(void)
 59 {
 60         alloc_bootmem_cpumask_var(&cpu_initialized_mask);
 61         alloc_bootmem_cpumask_var(&cpu_callin_mask);
 62         alloc_bootmem_cpumask_var(&cpu_callout_mask);
 63         alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
 64 }
 65 
 66 static void __cpuinit default_init(struct cpuinfo_x86 *c)
 67 {
 68 #ifdef CONFIG_X86_64
 69         cpu_detect_cache_sizes(c);
 70 #else
 71         /* Not much we can do here... */
 72         /* Check if at least it has cpuid */
 73         if (c->cpuid_level == -1) {
 74                 /* No cpuid. It must be an ancient CPU */
 75                 if (c->x86 == 4)
 76                         strcpy(c->x86_model_id, "486");
 77                 else if (c->x86 == 3)
 78                         strcpy(c->x86_model_id, "386");
 79         }
 80 #endif
 81 }
 82 
 83 static const struct cpu_dev __cpuinitconst default_cpu = {
 84         .c_init         = default_init,
 85         .c_vendor       = "Unknown",
 86         .c_x86_vendor   = X86_VENDOR_UNKNOWN,
 87 };
 88 
 89 static const struct cpu_dev *this_cpu __cpuinitdata = &default_cpu;
 90 
 91 DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
 92 #ifdef CONFIG_X86_64
 93         /*
 94          * We need valid kernel segments for data and code in long mode too
 95          * IRET will check the segment types  kkeil 2000/10/28
 96          * Also sysret mandates a special GDT layout
 97          *
 98          * TLS descriptors are currently at a different place compared to i386.
 99          * Hopefully nobody expects them at a fixed place (Wine?)
100          */
101         [GDT_ENTRY_KERNEL32_CS]         = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
102         [GDT_ENTRY_KERNEL_CS]           = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
103         [GDT_ENTRY_KERNEL_DS]           = GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
104         [GDT_ENTRY_DEFAULT_USER32_CS]   = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff),
105         [GDT_ENTRY_DEFAULT_USER_DS]     = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff),
106         [GDT_ENTRY_DEFAULT_USER_CS]     = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff),
107 #else
108         [GDT_ENTRY_KERNEL_CS]           = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff),
109         [GDT_ENTRY_KERNEL_DS]           = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
110         [GDT_ENTRY_DEFAULT_USER_CS]     = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff),
111         [GDT_ENTRY_DEFAULT_USER_DS]     = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff),
112         /*
113          * Segments used for calling PnP BIOS have byte granularity.
114          * They code segments and data segments have fixed 64k limits,
115          * the transfer segment sizes are set at run time.
116          */
117         /* 32-bit code */
118         [GDT_ENTRY_PNPBIOS_CS32]        = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
119         /* 16-bit code */
120         [GDT_ENTRY_PNPBIOS_CS16]        = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
121         /* 16-bit data */
122         [GDT_ENTRY_PNPBIOS_DS]          = GDT_ENTRY_INIT(0x0092, 0, 0xffff),
123         /* 16-bit data */
124         [GDT_ENTRY_PNPBIOS_TS1]         = GDT_ENTRY_INIT(0x0092, 0, 0),
125         /* 16-bit data */
126         [GDT_ENTRY_PNPBIOS_TS2]         = GDT_ENTRY_INIT(0x0092, 0, 0),
127         /*
128          * The APM segments have byte granularity and their bases
129          * are set at run time.  All have 64k limits.
130          */
131         /* 32-bit code */
132         [GDT_ENTRY_APMBIOS_BASE]        = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
133         /* 16-bit code */
134         [GDT_ENTRY_APMBIOS_BASE+1]      = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
135         /* data */
136         [GDT_ENTRY_APMBIOS_BASE+2]      = GDT_ENTRY_INIT(0x4092, 0, 0xffff),
137 
138         [GDT_ENTRY_ESPFIX_SS]           = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
139         [GDT_ENTRY_PERCPU]              = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
140         GDT_STACK_CANARY_INIT
141 #endif
142 } };
143 EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
144 
145 static int __init x86_xsave_setup(char *s)
146 {
147         setup_clear_cpu_cap(X86_FEATURE_XSAVE);
148         setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
149         setup_clear_cpu_cap(X86_FEATURE_AVX);
150         setup_clear_cpu_cap(X86_FEATURE_AVX2);
151         return 1;
152 }
153 __setup("noxsave", x86_xsave_setup);
154 
155 static int __init x86_xsaveopt_setup(char *s)
156 {
157         setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
158         return 1;
159 }
160 __setup("noxsaveopt", x86_xsaveopt_setup);
161 
162 #ifdef CONFIG_X86_32
163 static int cachesize_override __cpuinitdata = -1;
164 static int disable_x86_serial_nr __cpuinitdata = 1;
165 
166 static int __init cachesize_setup(char *str)
167 {
168         get_option(&str, &cachesize_override);
169         return 1;
170 }
171 __setup("cachesize=", cachesize_setup);
172 
173 static int __init x86_fxsr_setup(char *s)
174 {
175         setup_clear_cpu_cap(X86_FEATURE_FXSR);
176         setup_clear_cpu_cap(X86_FEATURE_XMM);
177         return 1;
178 }
179 __setup("nofxsr", x86_fxsr_setup);
180 
181 static int __init x86_sep_setup(char *s)
182 {
183         setup_clear_cpu_cap(X86_FEATURE_SEP);
184         return 1;
185 }
186 __setup("nosep", x86_sep_setup);
187 
188 /* Standard macro to see if a specific flag is changeable */
189 static inline int flag_is_changeable_p(u32 flag)
190 {
191         u32 f1, f2;
192 
193         /*
194          * Cyrix and IDT cpus allow disabling of CPUID
195          * so the code below may return different results
196          * when it is executed before and after enabling
197          * the CPUID. Add "volatile" to not allow gcc to
198          * optimize the subsequent calls to this function.
199          */
200         asm volatile ("pushfl           \n\t"
201                       "pushfl           \n\t"
202                       "popl %0          \n\t"
203                       "movl %0, %1      \n\t"
204                       "xorl %2, %0      \n\t"
205                       "pushl %0         \n\t"
206                       "popfl            \n\t"
207                       "pushfl           \n\t"
208                       "popl %0          \n\t"
209                       "popfl            \n\t"
210 
211                       : "=&r" (f1), "=&r" (f2)
212                       : "ir" (flag));
213 
214         return ((f1^f2) & flag) != 0;
215 }
216 
217 /* Probe for the CPUID instruction */
218 int __cpuinit have_cpuid_p(void)
219 {
220         return flag_is_changeable_p(X86_EFLAGS_ID);
221 }
222 
223 static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
224 {
225         unsigned long lo, hi;
226 
227         if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr)
228                 return;
229 
230         /* Disable processor serial number: */
231 
232         rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
233         lo |= 0x200000;
234         wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
235 
236         printk(KERN_NOTICE "CPU serial number disabled.\n");
237         clear_cpu_cap(c, X86_FEATURE_PN);
238 
239         /* Disabling the serial number may affect the cpuid level */
240         c->cpuid_level = cpuid_eax(0);
241 }
242 
243 static int __init x86_serial_nr_setup(char *s)
244 {
245         disable_x86_serial_nr = 0;
246         return 1;
247 }
248 __setup("serialnumber", x86_serial_nr_setup);
249 #else
250 static inline int flag_is_changeable_p(u32 flag)
251 {
252         return 1;
253 }
254 static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
255 {
256 }
257 #endif
258 
259 static __init int setup_disable_smep(char *arg)
260 {
261         setup_clear_cpu_cap(X86_FEATURE_SMEP);
262         return 1;
263 }
264 __setup("nosmep", setup_disable_smep);
265 
266 static __always_inline void setup_smep(struct cpuinfo_x86 *c)
267 {
268         if (cpu_has(c, X86_FEATURE_SMEP))
269                 set_in_cr4(X86_CR4_SMEP);
270 }
271 
272 static __init int setup_disable_smap(char *arg)
273 {
274         setup_clear_cpu_cap(X86_FEATURE_SMAP);
275         return 1;
276 }
277 __setup("nosmap", setup_disable_smap);
278 
279 static __always_inline void setup_smap(struct cpuinfo_x86 *c)
280 {
281         unsigned long eflags;
282 
283         /* This should have been cleared long ago */
284         raw_local_save_flags(eflags);
285         BUG_ON(eflags & X86_EFLAGS_AC);
286 
287         if (cpu_has(c, X86_FEATURE_SMAP))
288                 set_in_cr4(X86_CR4_SMAP);
289 }
290 
291 /*
292  * Some CPU features depend on higher CPUID levels, which may not always
293  * be available due to CPUID level capping or broken virtualization
294  * software.  Add those features to this table to auto-disable them.
295  */
296 struct cpuid_dependent_feature {
297         u32 feature;
298         u32 level;
299 };
300 
301 static const struct cpuid_dependent_feature __cpuinitconst
302 cpuid_dependent_features[] = {
303         { X86_FEATURE_MWAIT,            0x00000005 },
304         { X86_FEATURE_DCA,              0x00000009 },
305         { X86_FEATURE_XSAVE,            0x0000000d },
306         { 0, 0 }
307 };
308 
309 static void __cpuinit filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
310 {
311         const struct cpuid_dependent_feature *df;
312 
313         for (df = cpuid_dependent_features; df->feature; df++) {
314 
315                 if (!cpu_has(c, df->feature))
316                         continue;
317                 /*
318                  * Note: cpuid_level is set to -1 if unavailable, but
319                  * extended_extended_level is set to 0 if unavailable
320                  * and the legitimate extended levels are all negative
321                  * when signed; hence the weird messing around with
322                  * signs here...
323                  */
324                 if (!((s32)df->level < 0 ?
325                      (u32)df->level > (u32)c->extended_cpuid_level :
326                      (s32)df->level > (s32)c->cpuid_level))
327                         continue;
328 
329                 clear_cpu_cap(c, df->feature);
330                 if (!warn)
331                         continue;
332 
333                 printk(KERN_WARNING
334                        "CPU: CPU feature %s disabled, no CPUID level 0x%x\n",
335                                 x86_cap_flags[df->feature], df->level);
336         }
337 }
338 
339 /*
340  * Naming convention should be: <Name> [(<Codename>)]
341  * This table only is used unless init_<vendor>() below doesn't set it;
342  * in particular, if CPUID levels 0x80000002..4 are supported, this
343  * isn't used
344  */
345 
346 /* Look up CPU names by table lookup. */
347 static const char *__cpuinit table_lookup_model(struct cpuinfo_x86 *c)
348 {
349         const struct cpu_model_info *info;
350 
351         if (c->x86_model >= 16)
352                 return NULL;    /* Range check */
353 
354         if (!this_cpu)
355                 return NULL;
356 
357         info = this_cpu->c_models;
358 
359         while (info && info->family) {
360                 if (info->family == c->x86)
361                         return info->model_names[c->x86_model];
362                 info++;
363         }
364         return NULL;            /* Not found */
365 }
366 
367 __u32 cpu_caps_cleared[NCAPINTS] __cpuinitdata;
368 __u32 cpu_caps_set[NCAPINTS] __cpuinitdata;
369 
370 void load_percpu_segment(int cpu)
371 {
372 #ifdef CONFIG_X86_32
373         loadsegment(fs, __KERNEL_PERCPU);
374 #else
375         loadsegment(gs, 0);
376         wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
377 #endif
378         load_stack_canary_segment();
379 }
380 
381 /*
382  * Current gdt points %fs at the "master" per-cpu area: after this,
383  * it's on the real one.
384  */
385 void switch_to_new_gdt(int cpu)
386 {
387         struct desc_ptr gdt_descr;
388 
389         gdt_descr.address = (long)get_cpu_gdt_table(cpu);
390         gdt_descr.size = GDT_SIZE - 1;
391         load_gdt(&gdt_descr);
392         /* Reload the per-cpu base */
393 
394         load_percpu_segment(cpu);
395 }
396 
397 static const struct cpu_dev *__cpuinitdata cpu_devs[X86_VENDOR_NUM] = {};
398 
399 static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
400 {
401         unsigned int *v;
402         char *p, *q;
403 
404         if (c->extended_cpuid_level < 0x80000004)
405                 return;
406 
407         v = (unsigned int *)c->x86_model_id;
408         cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
409         cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
410         cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
411         c->x86_model_id[48] = 0;
412 
413         /*
414          * Intel chips right-justify this string for some dumb reason;
415          * undo that brain damage:
416          */
417         p = q = &c->x86_model_id[0];
418         while (*p == ' ')
419                 p++;
420         if (p != q) {
421                 while (*p)
422                         *q++ = *p++;
423                 while (q <= &c->x86_model_id[48])
424                         *q++ = '\0';    /* Zero-pad the rest */
425         }
426 }
427 
428 void __cpuinit cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
429 {
430         unsigned int n, dummy, ebx, ecx, edx, l2size;
431 
432         n = c->extended_cpuid_level;
433 
434         if (n >= 0x80000005) {
435                 cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
436                 c->x86_cache_size = (ecx>>24) + (edx>>24);
437 #ifdef CONFIG_X86_64
438                 /* On K8 L1 TLB is inclusive, so don't count it */
439                 c->x86_tlbsize = 0;
440 #endif
441         }
442 
443         if (n < 0x80000006)     /* Some chips just has a large L1. */
444                 return;
445 
446         cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
447         l2size = ecx >> 16;
448 
449 #ifdef CONFIG_X86_64
450         c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
451 #else
452         /* do processor-specific cache resizing */
453         if (this_cpu->c_size_cache)
454                 l2size = this_cpu->c_size_cache(c, l2size);
455 
456         /* Allow user to override all this if necessary. */
457         if (cachesize_override != -1)
458                 l2size = cachesize_override;
459 
460         if (l2size == 0)
461                 return;         /* Again, no L2 cache is possible */
462 #endif
463 
464         c->x86_cache_size = l2size;
465 }
466 
467 u16 __read_mostly tlb_lli_4k[NR_INFO];
468 u16 __read_mostly tlb_lli_2m[NR_INFO];
469 u16 __read_mostly tlb_lli_4m[NR_INFO];
470 u16 __read_mostly tlb_lld_4k[NR_INFO];
471 u16 __read_mostly tlb_lld_2m[NR_INFO];
472 u16 __read_mostly tlb_lld_4m[NR_INFO];
473 
474 /*
475  * tlb_flushall_shift shows the balance point in replacing cr3 write
476  * with multiple 'invlpg'. It will do this replacement when
477  *   flush_tlb_lines <= active_lines/2^tlb_flushall_shift.
478  * If tlb_flushall_shift is -1, means the replacement will be disabled.
479  */
480 s8  __read_mostly tlb_flushall_shift = -1;
481 
482 void __cpuinit cpu_detect_tlb(struct cpuinfo_x86 *c)
483 {
484         if (this_cpu->c_detect_tlb)
485                 this_cpu->c_detect_tlb(c);
486 
487         printk(KERN_INFO "Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n" \
488                 "Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d\n"          \
489                 "tlb_flushall_shift: %d\n",
490                 tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES],
491                 tlb_lli_4m[ENTRIES], tlb_lld_4k[ENTRIES],
492                 tlb_lld_2m[ENTRIES], tlb_lld_4m[ENTRIES],
493                 tlb_flushall_shift);
494 }
495 
496 void __cpuinit detect_ht(struct cpuinfo_x86 *c)
497 {
498 #ifdef CONFIG_X86_HT
499         u32 eax, ebx, ecx, edx;
500         int index_msb, core_bits;
501         static bool printed;
502 
503         if (!cpu_has(c, X86_FEATURE_HT))
504                 return;
505 
506         if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
507                 goto out;
508 
509         if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
510                 return;
511 
512         cpuid(1, &eax, &ebx, &ecx, &edx);
513 
514         smp_num_siblings = (ebx & 0xff0000) >> 16;
515 
516         if (smp_num_siblings == 1) {
517                 printk_once(KERN_INFO "CPU0: Hyper-Threading is disabled\n");
518                 goto out;
519         }
520 
521         if (smp_num_siblings <= 1)
522                 goto out;
523 
524         index_msb = get_count_order(smp_num_siblings);
525         c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
526 
527         smp_num_siblings = smp_num_siblings / c->x86_max_cores;
528 
529         index_msb = get_count_order(smp_num_siblings);
530 
531         core_bits = get_count_order(c->x86_max_cores);
532 
533         c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
534                                        ((1 << core_bits) - 1);
535 
536 out:
537         if (!printed && (c->x86_max_cores * smp_num_siblings) > 1) {
538                 printk(KERN_INFO  "CPU: Physical Processor ID: %d\n",
539                        c->phys_proc_id);
540                 printk(KERN_INFO  "CPU: Processor Core ID: %d\n",
541                        c->cpu_core_id);
542                 printed = 1;
543         }
544 #endif
545 }
546 
547 static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
548 {
549         char *v = c->x86_vendor_id;
550         int i;
551 
552         for (i = 0; i < X86_VENDOR_NUM; i++) {
553                 if (!cpu_devs[i])
554                         break;
555 
556                 if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
557                     (cpu_devs[i]->c_ident[1] &&
558                      !strcmp(v, cpu_devs[i]->c_ident[1]))) {
559 
560                         this_cpu = cpu_devs[i];
561                         c->x86_vendor = this_cpu->c_x86_vendor;
562                         return;
563                 }
564         }
565 
566         printk_once(KERN_ERR
567                         "CPU: vendor_id '%s' unknown, using generic init.\n" \
568                         "CPU: Your system may be unstable.\n", v);
569 
570         c->x86_vendor = X86_VENDOR_UNKNOWN;
571         this_cpu = &default_cpu;
572 }
573 
574 void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
575 {
576         /* Get vendor name */
577         cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
578               (unsigned int *)&c->x86_vendor_id[0],
579               (unsigned int *)&c->x86_vendor_id[8],
580               (unsigned int *)&c->x86_vendor_id[4]);
581 
582         c->x86 = 4;
583         /* Intel-defined flags: level 0x00000001 */
584         if (c->cpuid_level >= 0x00000001) {
585                 u32 junk, tfms, cap0, misc;
586 
587                 cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
588                 c->x86 = (tfms >> 8) & 0xf;
589                 c->x86_model = (tfms >> 4) & 0xf;
590                 c->x86_mask = tfms & 0xf;
591 
592                 if (c->x86 == 0xf)
593                         c->x86 += (tfms >> 20) & 0xff;
594                 if (c->x86 >= 0x6)
595                         c->x86_model += ((tfms >> 16) & 0xf) << 4;
596 
597                 if (cap0 & (1<<19)) {
598                         c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
599                         c->x86_cache_alignment = c->x86_clflush_size;
600                 }
601         }
602 }
603 
604 void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
605 {
606         u32 tfms, xlvl;
607         u32 ebx;
608 
609         /* Intel-defined flags: level 0x00000001 */
610         if (c->cpuid_level >= 0x00000001) {
611                 u32 capability, excap;
612 
613                 cpuid(0x00000001, &tfms, &ebx, &excap, &capability);
614                 c->x86_capability[0] = capability;
615                 c->x86_capability[4] = excap;
616         }
617 
618         /* Additional Intel-defined flags: level 0x00000007 */
619         if (c->cpuid_level >= 0x00000007) {
620                 u32 eax, ebx, ecx, edx;
621 
622                 cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);
623 
624                 c->x86_capability[9] = ebx;
625         }
626 
627         /* AMD-defined flags: level 0x80000001 */
628         xlvl = cpuid_eax(0x80000000);
629         c->extended_cpuid_level = xlvl;
630 
631         if ((xlvl & 0xffff0000) == 0x80000000) {
632                 if (xlvl >= 0x80000001) {
633                         c->x86_capability[1] = cpuid_edx(0x80000001);
634                         c->x86_capability[6] = cpuid_ecx(0x80000001);
635                 }
636         }
637 
638         if (c->extended_cpuid_level >= 0x80000008) {
639                 u32 eax = cpuid_eax(0x80000008);
640 
641                 c->x86_virt_bits = (eax >> 8) & 0xff;
642                 c->x86_phys_bits = eax & 0xff;
643         }
644 #ifdef CONFIG_X86_32
645         else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36))
646                 c->x86_phys_bits = 36;
647 #endif
648 
649         if (c->extended_cpuid_level >= 0x80000007)
650                 c->x86_power = cpuid_edx(0x80000007);
651 
652         init_scattered_cpuid_features(c);
653 }
654 
655 static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
656 {
657 #ifdef CONFIG_X86_32
658         int i;
659 
660         /*
661          * First of all, decide if this is a 486 or higher
662          * It's a 486 if we can modify the AC flag
663          */
664         if (flag_is_changeable_p(X86_EFLAGS_AC))
665                 c->x86 = 4;
666         else
667                 c->x86 = 3;
668 
669         for (i = 0; i < X86_VENDOR_NUM; i++)
670                 if (cpu_devs[i] && cpu_devs[i]->c_identify) {
671                         c->x86_vendor_id[0] = 0;
672                         cpu_devs[i]->c_identify(c);
673                         if (c->x86_vendor_id[0]) {
674                                 get_cpu_vendor(c);
675                                 break;
676                         }
677                 }
678 #endif
679 }
680 
681 /*
682  * Do minimum CPU detection early.
683  * Fields really needed: vendor, cpuid_level, family, model, mask,
684  * cache alignment.
685  * The others are not touched to avoid unwanted side effects.
686  *
687  * WARNING: this function is only called on the BP.  Don't add code here
688  * that is supposed to run on all CPUs.
689  */
690 static void __init early_identify_cpu(struct cpuinfo_x86 *c)
691 {
692 #ifdef CONFIG_X86_64
693         c->x86_clflush_size = 64;
694         c->x86_phys_bits = 36;
695         c->x86_virt_bits = 48;
696 #else
697         c->x86_clflush_size = 32;
698         c->x86_phys_bits = 32;
699         c->x86_virt_bits = 32;
700 #endif
701         c->x86_cache_alignment = c->x86_clflush_size;
702 
703         memset(&c->x86_capability, 0, sizeof c->x86_capability);
704         c->extended_cpuid_level = 0;
705 
706         if (!have_cpuid_p())
707                 identify_cpu_without_cpuid(c);
708 
709         /* cyrix could have cpuid enabled via c_identify()*/
710         if (!have_cpuid_p())
711                 return;
712 
713         cpu_detect(c);
714 
715         get_cpu_vendor(c);
716 
717         get_cpu_cap(c);
718 
719         if (this_cpu->c_early_init)
720                 this_cpu->c_early_init(c);
721 
722         c->cpu_index = 0;
723         filter_cpuid_features(c, false);
724 
725         if (this_cpu->c_bsp_init)
726                 this_cpu->c_bsp_init(c);
727 }
728 
729 void __init early_cpu_init(void)
730 {
731         const struct cpu_dev *const *cdev;
732         int count = 0;
733 
734 #ifdef CONFIG_PROCESSOR_SELECT
735         printk(KERN_INFO "KERNEL supported cpus:\n");
736 #endif
737 
738         for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
739                 const struct cpu_dev *cpudev = *cdev;
740 
741                 if (count >= X86_VENDOR_NUM)
742                         break;
743                 cpu_devs[count] = cpudev;
744                 count++;
745 
746 #ifdef CONFIG_PROCESSOR_SELECT
747                 {
748                         unsigned int j;
749 
750                         for (j = 0; j < 2; j++) {
751                                 if (!cpudev->c_ident[j])
752                                         continue;
753                                 printk(KERN_INFO "  %s %s\n", cpudev->c_vendor,
754                                         cpudev->c_ident[j]);
755                         }
756                 }
757 #endif
758         }
759         early_identify_cpu(&boot_cpu_data);
760 }
761 
762 /*
763  * The NOPL instruction is supposed to exist on all CPUs of family >= 6;
764  * unfortunately, that's not true in practice because of early VIA
765  * chips and (more importantly) broken virtualizers that are not easy
766  * to detect. In the latter case it doesn't even *fail* reliably, so
767  * probing for it doesn't even work. Disable it completely on 32-bit
768  * unless we can find a reliable way to detect all the broken cases.
769  * Enable it explicitly on 64-bit for non-constant inputs of cpu_has().
770  */
771 static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
772 {
773 #ifdef CONFIG_X86_32
774         clear_cpu_cap(c, X86_FEATURE_NOPL);
775 #else
776         set_cpu_cap(c, X86_FEATURE_NOPL);
777 #endif
778 }
779 
780 static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
781 {
782         c->extended_cpuid_level = 0;
783 
784         if (!have_cpuid_p())
785                 identify_cpu_without_cpuid(c);
786 
787         /* cyrix could have cpuid enabled via c_identify()*/
788         if (!have_cpuid_p())
789                 return;
790 
791         cpu_detect(c);
792 
793         get_cpu_vendor(c);
794 
795         get_cpu_cap(c);
796 
797         if (c->cpuid_level >= 0x00000001) {
798                 c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
799 #ifdef CONFIG_X86_32
800 # ifdef CONFIG_X86_HT
801                 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
802 # else
803                 c->apicid = c->initial_apicid;
804 # endif
805 #endif
806                 c->phys_proc_id = c->initial_apicid;
807         }
808 
809         get_model_name(c); /* Default name */
810 
811         detect_nopl(c);
812 }
813 
814 /*
815  * This does the hard work of actually picking apart the CPU stuff...
816  */
817 static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
818 {
819         int i;
820 
821         c->loops_per_jiffy = loops_per_jiffy;
822         c->x86_cache_size = -1;
823         c->x86_vendor = X86_VENDOR_UNKNOWN;
824         c->x86_model = c->x86_mask = 0; /* So far unknown... */
825         c->x86_vendor_id[0] = '\0'; /* Unset */
826         c->x86_model_id[0] = '\0';  /* Unset */
827         c->x86_max_cores = 1;
828         c->x86_coreid_bits = 0;
829 #ifdef CONFIG_X86_64
830         c->x86_clflush_size = 64;
831         c->x86_phys_bits = 36;
832         c->x86_virt_bits = 48;
833 #else
834         c->cpuid_level = -1;    /* CPUID not detected */
835         c->x86_clflush_size = 32;
836         c->x86_phys_bits = 32;
837         c->x86_virt_bits = 32;
838 #endif
839         c->x86_cache_alignment = c->x86_clflush_size;
840         memset(&c->x86_capability, 0, sizeof c->x86_capability);
841 
842         generic_identify(c);
843 
844         if (this_cpu->c_identify)
845                 this_cpu->c_identify(c);
846 
847         /* Clear/Set all flags overriden by options, after probe */
848         for (i = 0; i < NCAPINTS; i++) {
849                 c->x86_capability[i] &= ~cpu_caps_cleared[i];
850                 c->x86_capability[i] |= cpu_caps_set[i];
851         }
852 
853 #ifdef CONFIG_X86_64
854         c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
855 #endif
856 
857         /*
858          * Vendor-specific initialization.  In this section we
859          * canonicalize the feature flags, meaning if there are
860          * features a certain CPU supports which CPUID doesn't
861          * tell us, CPUID claiming incorrect flags, or other bugs,
862          * we handle them here.
863          *
864          * At the end of this section, c->x86_capability better
865          * indicate the features this CPU genuinely supports!
866          */
867         if (this_cpu->c_init)
868                 this_cpu->c_init(c);
869 
870         /* Disable the PN if appropriate */
871         squash_the_stupid_serial_number(c);
872 
873         /* Set up SMEP/SMAP */
874         setup_smep(c);
875         setup_smap(c);
876 
877         /*
878          * The vendor-specific functions might have changed features.
879          * Now we do "generic changes."
880          */
881 
882         /* Filter out anything that depends on CPUID levels we don't have */
883         filter_cpuid_features(c, true);
884 
885         /* If the model name is still unset, do table lookup. */
886         if (!c->x86_model_id[0]) {
887                 const char *p;
888                 p = table_lookup_model(c);
889                 if (p)
890                         strcpy(c->x86_model_id, p);
891                 else
892                         /* Last resort... */
893                         sprintf(c->x86_model_id, "%02x/%02x",
894                                 c->x86, c->x86_model);
895         }
896 
897 #ifdef CONFIG_X86_64
898         detect_ht(c);
899 #endif
900 
901         init_hypervisor(c);
902         x86_init_rdrand(c);
903 
904         /*
905          * Clear/Set all flags overriden by options, need do it
906          * before following smp all cpus cap AND.
907          */
908         for (i = 0; i < NCAPINTS; i++) {
909                 c->x86_capability[i] &= ~cpu_caps_cleared[i];
910                 c->x86_capability[i] |= cpu_caps_set[i];
911         }
912 
913         /*
914          * On SMP, boot_cpu_data holds the common feature set between
915          * all CPUs; so make sure that we indicate which features are
916          * common between the CPUs.  The first time this routine gets
917          * executed, c == &boot_cpu_data.
918          */
919         if (c != &boot_cpu_data) {
920                 /* AND the already accumulated flags with these */
921                 for (i = 0; i < NCAPINTS; i++)
922                         boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
923         }
924 
925         /* Init Machine Check Exception if available. */
926         mcheck_cpu_init(c);
927 
928         select_idle_routine(c);
929 
930 #ifdef CONFIG_NUMA
931         numa_add_cpu(smp_processor_id());
932 #endif
933 }
934 
935 #ifdef CONFIG_X86_64
936 static void vgetcpu_set_mode(void)
937 {
938         if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
939                 vgetcpu_mode = VGETCPU_RDTSCP;
940         else
941                 vgetcpu_mode = VGETCPU_LSL;
942 }
943 #endif
944 
945 void __init identify_boot_cpu(void)
946 {
947         identify_cpu(&boot_cpu_data);
948         init_amd_e400_c1e_mask();
949 #ifdef CONFIG_X86_32
950         sysenter_setup();
951         enable_sep_cpu();
952 #else
953         vgetcpu_set_mode();
954 #endif
955         cpu_detect_tlb(&boot_cpu_data);
956 }
957 
958 void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
959 {
960         BUG_ON(c == &boot_cpu_data);
961         identify_cpu(c);
962 #ifdef CONFIG_X86_32
963         enable_sep_cpu();
964 #endif
965         mtrr_ap_init();
966 }
967 
968 struct msr_range {
969         unsigned        min;
970         unsigned        max;
971 };
972 
973 static const struct msr_range msr_range_array[] __cpuinitconst = {
974         { 0x00000000, 0x00000418},
975         { 0xc0000000, 0xc000040b},
976         { 0xc0010000, 0xc0010142},
977         { 0xc0011000, 0xc001103b},
978 };
979 
980 static void __cpuinit __print_cpu_msr(void)
981 {
982         unsigned index_min, index_max;
983         unsigned index;
984         u64 val;
985         int i;
986 
987         for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
988                 index_min = msr_range_array[i].min;
989                 index_max = msr_range_array[i].max;
990 
991                 for (index = index_min; index < index_max; index++) {
992                         if (rdmsrl_safe(index, &val))
993                                 continue;
994                         printk(KERN_INFO " MSR%08x: %016llx\n", index, val);
995                 }
996         }
997 }
998 
999 static int show_msr __cpuinitdata;
1000 
1001 static __init int setup_show_msr(char *arg)
1002 {
1003         int num;
1004 
1005         get_option(&arg, &num);
1006 
1007         if (num > 0)
1008                 show_msr = num;
1009         return 1;
1010 }
1011 __setup("show_msr=", setup_show_msr);
1012 
1013 static __init int setup_noclflush(char *arg)
1014 {
1015         setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
1016         return 1;
1017 }
1018 __setup("noclflush", setup_noclflush);
1019 
1020 void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
1021 {
1022         const char *vendor = NULL;
1023 
1024         if (c->x86_vendor < X86_VENDOR_NUM) {
1025                 vendor = this_cpu->c_vendor;
1026         } else {
1027                 if (c->cpuid_level >= 0)
1028                         vendor = c->x86_vendor_id;
1029         }
1030 
1031         if (vendor && !strstr(c->x86_model_id, vendor))
1032                 printk(KERN_CONT "%s ", vendor);
1033 
1034         if (c->x86_model_id[0])
1035                 printk(KERN_CONT "%s", strim(c->x86_model_id));
1036         else
1037                 printk(KERN_CONT "%d86", c->x86);
1038 
1039         printk(KERN_CONT " (fam: %02x, model: %02x", c->x86, c->x86_model);
1040 
1041         if (c->x86_mask || c->cpuid_level >= 0)
1042                 printk(KERN_CONT ", stepping: %02x)\n", c->x86_mask);
1043         else
1044                 printk(KERN_CONT ")\n");
1045 
1046         print_cpu_msr(c);
1047 }
1048 
1049 void __cpuinit print_cpu_msr(struct cpuinfo_x86 *c)
1050 {
1051         if (c->cpu_index < show_msr)
1052                 __print_cpu_msr();
1053 }
1054 
1055 static __init int setup_disablecpuid(char *arg)
1056 {
1057         int bit;
1058 
1059         if (get_option(&arg, &bit) && bit < NCAPINTS*32)
1060                 setup_clear_cpu_cap(bit);
1061         else
1062                 return 0;
1063 
1064         return 1;
1065 }
1066 __setup("clearcpuid=", setup_disablecpuid);
1067 
1068 #ifdef CONFIG_X86_64
1069 struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table };
1070 struct desc_ptr nmi_idt_descr = { NR_VECTORS * 16 - 1,
1071                                     (unsigned long) nmi_idt_table };
1072 
1073 DEFINE_PER_CPU_FIRST(union irq_stack_union,
1074                      irq_stack_union) __aligned(PAGE_SIZE);
1075 
1076 /*
1077  * The following four percpu variables are hot.  Align current_task to
1078  * cacheline size such that all four fall in the same cacheline.
1079  */
1080 DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
1081         &init_task;
1082 EXPORT_PER_CPU_SYMBOL(current_task);
1083 
1084 DEFINE_PER_CPU(unsigned long, kernel_stack) =
1085         (unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
1086 EXPORT_PER_CPU_SYMBOL(kernel_stack);
1087 
1088 DEFINE_PER_CPU(char *, irq_stack_ptr) =
1089         init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
1090 
1091 DEFINE_PER_CPU(unsigned int, irq_count) = -1;
1092 
1093 DEFINE_PER_CPU(struct task_struct *, fpu_owner_task);
1094 
1095 /*
1096  * Special IST stacks which the CPU switches to when it calls
1097  * an IST-marked descriptor entry. Up to 7 stacks (hardware
1098  * limit), all of them are 4K, except the debug stack which
1099  * is 8K.
1100  */
1101 static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
1102           [0 ... N_EXCEPTION_STACKS - 1]        = EXCEPTION_STKSZ,
1103           [DEBUG_STACK - 1]                     = DEBUG_STKSZ
1104 };
1105 
1106 static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
1107         [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
1108 
1109 /* May not be marked __init: used by software suspend */
1110 void syscall_init(void)
1111 {
1112         /*
1113          * LSTAR and STAR live in a bit strange symbiosis.
1114          * They both write to the same internal register. STAR allows to
1115          * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
1116          */
1117         wrmsrl(MSR_STAR,  ((u64)__USER32_CS)<<48  | ((u64)__KERNEL_CS)<<32);
1118         wrmsrl(MSR_LSTAR, system_call);
1119         wrmsrl(MSR_CSTAR, ignore_sysret);
1120 
1121 #ifdef CONFIG_IA32_EMULATION
1122         syscall32_cpu_init();
1123 #endif
1124 
1125         /* Flags to clear on syscall */
1126         wrmsrl(MSR_SYSCALL_MASK,
1127                X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|
1128                X86_EFLAGS_IOPL|X86_EFLAGS_AC);
1129 }
1130 
1131 /*
1132  * Copies of the original ist values from the tss are only accessed during
1133  * debugging, no special alignment required.
1134  */
1135 DEFINE_PER_CPU(struct orig_ist, orig_ist);
1136 
1137 static DEFINE_PER_CPU(unsigned long, debug_stack_addr);
1138 DEFINE_PER_CPU(int, debug_stack_usage);
1139 
1140 int is_debug_stack(unsigned long addr)
1141 {
1142         return __get_cpu_var(debug_stack_usage) ||
1143                 (addr <= __get_cpu_var(debug_stack_addr) &&
1144                  addr > (__get_cpu_var(debug_stack_addr) - DEBUG_STKSZ));
1145 }
1146 
1147 static DEFINE_PER_CPU(u32, debug_stack_use_ctr);
1148 
1149 void debug_stack_set_zero(void)
1150 {
1151         this_cpu_inc(debug_stack_use_ctr);
1152         load_idt((const struct desc_ptr *)&nmi_idt_descr);
1153 }
1154 
1155 void debug_stack_reset(void)
1156 {
1157         if (WARN_ON(!this_cpu_read(debug_stack_use_ctr)))
1158                 return;
1159         if (this_cpu_dec_return(debug_stack_use_ctr) == 0)
1160                 load_idt((const struct desc_ptr *)&idt_descr);
1161 }
1162 
1163 #else   /* CONFIG_X86_64 */
1164 
1165 DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
1166 EXPORT_PER_CPU_SYMBOL(current_task);
1167 DEFINE_PER_CPU(struct task_struct *, fpu_owner_task);
1168 
1169 #ifdef CONFIG_CC_STACKPROTECTOR
1170 DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
1171 #endif
1172 
1173 #endif  /* CONFIG_X86_64 */
1174 
1175 /*
1176  * Clear all 6 debug registers:
1177  */
1178 static void clear_all_debug_regs(void)
1179 {
1180         int i;
1181 
1182         for (i = 0; i < 8; i++) {
1183                 /* Ignore db4, db5 */
1184                 if ((i == 4) || (i == 5))
1185                         continue;
1186 
1187                 set_debugreg(0, i);
1188         }
1189 }
1190 
1191 #ifdef CONFIG_KGDB
1192 /*
1193  * Restore debug regs if using kgdbwait and you have a kernel debugger
1194  * connection established.
1195  */
1196 static void dbg_restore_debug_regs(void)
1197 {
1198         if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break))
1199                 arch_kgdb_ops.correct_hw_break();
1200 }
1201 #else /* ! CONFIG_KGDB */
1202 #define dbg_restore_debug_regs()
1203 #endif /* ! CONFIG_KGDB */
1204 
1205 /*
1206  * cpu_init() initializes state that is per-CPU. Some data is already
1207  * initialized (naturally) in the bootstrap process, such as the GDT
1208  * and IDT. We reload them nevertheless, this function acts as a
1209  * 'CPU state barrier', nothing should get across.
1210  * A lot of state is already set up in PDA init for 64 bit
1211  */
1212 #ifdef CONFIG_X86_64
1213 
1214 void __cpuinit cpu_init(void)
1215 {
1216         struct orig_ist *oist;
1217         struct task_struct *me;
1218         struct tss_struct *t;
1219         unsigned long v;
1220         int cpu;
1221         int i;
1222 
1223         /*
1224          * Load microcode on this cpu if a valid microcode is available.
1225          * This is early microcode loading procedure.
1226          */
1227         load_ucode_ap();
1228 
1229         cpu = stack_smp_processor_id();
1230         t = &per_cpu(init_tss, cpu);
1231         oist = &per_cpu(orig_ist, cpu);
1232 
1233 #ifdef CONFIG_NUMA
1234         if (this_cpu_read(numa_node) == 0 &&
1235             early_cpu_to_node(cpu) != NUMA_NO_NODE)
1236                 set_numa_node(early_cpu_to_node(cpu));
1237 #endif
1238 
1239         me = current;
1240 
1241         if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask))
1242                 panic("CPU#%d already initialized!\n", cpu);
1243 
1244         pr_debug("Initializing CPU#%d\n", cpu);
1245 
1246         clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1247 
1248         /*
1249          * Initialize the per-CPU GDT with the boot GDT,
1250          * and set up the GDT descriptor:
1251          */
1252 
1253         switch_to_new_gdt(cpu);
1254         loadsegment(fs, 0);
1255 
1256         load_idt((const struct desc_ptr *)&idt_descr);
1257 
1258         memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
1259         syscall_init();
1260 
1261         wrmsrl(MSR_FS_BASE, 0);
1262         wrmsrl(MSR_KERNEL_GS_BASE, 0);
1263         barrier();
1264 
1265         x86_configure_nx();
1266         enable_x2apic();
1267 
1268         /*
1269          * set up and load the per-CPU TSS
1270          */
1271         if (!oist->ist[0]) {
1272                 char *estacks = per_cpu(exception_stacks, cpu);
1273 
1274                 for (v = 0; v < N_EXCEPTION_STACKS; v++) {
1275                         estacks += exception_stack_sizes[v];
1276                         oist->ist[v] = t->x86_tss.ist[v] =
1277                                         (unsigned long)estacks;
1278                         if (v == DEBUG_STACK-1)
1279                                 per_cpu(debug_stack_addr, cpu) = (unsigned long)estacks;
1280                 }
1281         }
1282 
1283         t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
1284 
1285         /*
1286          * <= is required because the CPU will access up to
1287          * 8 bits beyond the end of the IO permission bitmap.
1288          */
1289         for (i = 0; i <= IO_BITMAP_LONGS; i++)
1290                 t->io_bitmap[i] = ~0UL;
1291 
1292         atomic_inc(&init_mm.mm_count);
1293         me->active_mm = &init_mm;
1294         BUG_ON(me->mm);
1295         enter_lazy_tlb(&init_mm, me);
1296 
1297         load_sp0(t, &current->thread);
1298         set_tss_desc(cpu, t);
1299         load_TR_desc();
1300         load_LDT(&init_mm.context);
1301 
1302         clear_all_debug_regs();
1303         dbg_restore_debug_regs();
1304 
1305         fpu_init();
1306 
1307         if (is_uv_system())
1308                 uv_cpu_init();
1309 }
1310 
1311 #else
1312 
1313 void __cpuinit cpu_init(void)
1314 {
1315         int cpu = smp_processor_id();
1316         struct task_struct *curr = current;
1317         struct tss_struct *t = &per_cpu(init_tss, cpu);
1318         struct thread_struct *thread = &curr->thread;
1319 
1320         show_ucode_info_early();
1321 
1322         if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)) {
1323                 printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
1324                 for (;;)
1325                         local_irq_enable();
1326         }
1327 
1328         printk(KERN_INFO "Initializing CPU#%d\n", cpu);
1329 
1330         if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
1331                 clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1332 
1333         load_idt(&idt_descr);
1334         switch_to_new_gdt(cpu);
1335 
1336         /*
1337          * Set up and load the per-CPU TSS and LDT
1338          */
1339         atomic_inc(&init_mm.mm_count);
1340         curr->active_mm = &init_mm;
1341         BUG_ON(curr->mm);
1342         enter_lazy_tlb(&init_mm, curr);
1343 
1344         load_sp0(t, thread);
1345         set_tss_desc(cpu, t);
1346         load_TR_desc();
1347         load_LDT(&init_mm.context);
1348 
1349         t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
1350 
1351 #ifdef CONFIG_DOUBLEFAULT
1352         /* Set up doublefault TSS pointer in the GDT */
1353         __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
1354 #endif
1355 
1356         clear_all_debug_regs();
1357         dbg_restore_debug_regs();
1358 
1359         fpu_init();
1360 }
1361 #endif
1362 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds