common.c 30 KB

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  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. #include <asm/stackprotector.h>
  15. #include <asm/perf_event.h>
  16. #include <asm/mmu_context.h>
  17. #include <asm/hypervisor.h>
  18. #include <asm/processor.h>
  19. #include <asm/sections.h>
  20. #include <linux/topology.h>
  21. #include <linux/cpumask.h>
  22. #include <asm/pgtable.h>
  23. #include <asm/atomic.h>
  24. #include <asm/proto.h>
  25. #include <asm/setup.h>
  26. #include <asm/apic.h>
  27. #include <asm/desc.h>
  28. #include <asm/i387.h>
  29. #include <asm/mtrr.h>
  30. #include <linux/numa.h>
  31. #include <asm/asm.h>
  32. #include <asm/cpu.h>
  33. #include <asm/mce.h>
  34. #include <asm/msr.h>
  35. #include <asm/pat.h>
  36. #ifdef CONFIG_X86_LOCAL_APIC
  37. #include <asm/uv/uv.h>
  38. #endif
  39. #include "cpu.h"
  40. /* all of these masks are initialized in setup_cpu_local_masks() */
  41. cpumask_var_t cpu_initialized_mask;
  42. cpumask_var_t cpu_callout_mask;
  43. cpumask_var_t cpu_callin_mask;
  44. /* representing cpus for which sibling maps can be computed */
  45. cpumask_var_t cpu_sibling_setup_mask;
  46. /* correctly size the local cpu masks */
  47. void __init setup_cpu_local_masks(void)
  48. {
  49. alloc_bootmem_cpumask_var(&cpu_initialized_mask);
  50. alloc_bootmem_cpumask_var(&cpu_callin_mask);
  51. alloc_bootmem_cpumask_var(&cpu_callout_mask);
  52. alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
  53. }
  54. static void __cpuinit default_init(struct cpuinfo_x86 *c)
  55. {
  56. #ifdef CONFIG_X86_64
  57. cpu_detect_cache_sizes(c);
  58. #else
  59. /* Not much we can do here... */
  60. /* Check if at least it has cpuid */
  61. if (c->cpuid_level == -1) {
  62. /* No cpuid. It must be an ancient CPU */
  63. if (c->x86 == 4)
  64. strcpy(c->x86_model_id, "486");
  65. else if (c->x86 == 3)
  66. strcpy(c->x86_model_id, "386");
  67. }
  68. #endif
  69. }
  70. static const struct cpu_dev __cpuinitconst default_cpu = {
  71. .c_init = default_init,
  72. .c_vendor = "Unknown",
  73. .c_x86_vendor = X86_VENDOR_UNKNOWN,
  74. };
  75. static const struct cpu_dev *this_cpu __cpuinitdata = &default_cpu;
  76. DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
  77. #ifdef CONFIG_X86_64
  78. /*
  79. * We need valid kernel segments for data and code in long mode too
  80. * IRET will check the segment types kkeil 2000/10/28
  81. * Also sysret mandates a special GDT layout
  82. *
  83. * TLS descriptors are currently at a different place compared to i386.
  84. * Hopefully nobody expects them at a fixed place (Wine?)
  85. */
  86. [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
  87. [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
  88. [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
  89. [GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff),
  90. [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff),
  91. [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff),
  92. #else
  93. [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff),
  94. [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
  95. [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff),
  96. [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff),
  97. /*
  98. * Segments used for calling PnP BIOS have byte granularity.
  99. * They code segments and data segments have fixed 64k limits,
  100. * the transfer segment sizes are set at run time.
  101. */
  102. /* 32-bit code */
  103. [GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
  104. /* 16-bit code */
  105. [GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
  106. /* 16-bit data */
  107. [GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(0x0092, 0, 0xffff),
  108. /* 16-bit data */
  109. [GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(0x0092, 0, 0),
  110. /* 16-bit data */
  111. [GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(0x0092, 0, 0),
  112. /*
  113. * The APM segments have byte granularity and their bases
  114. * are set at run time. All have 64k limits.
  115. */
  116. /* 32-bit code */
  117. [GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
  118. /* 16-bit code */
  119. [GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
  120. /* data */
  121. [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff),
  122. [GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
  123. [GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
  124. GDT_STACK_CANARY_INIT
  125. #endif
  126. } };
  127. EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
  128. static int __init x86_xsave_setup(char *s)
  129. {
  130. setup_clear_cpu_cap(X86_FEATURE_XSAVE);
  131. setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
  132. return 1;
  133. }
  134. __setup("noxsave", x86_xsave_setup);
  135. static int __init x86_xsaveopt_setup(char *s)
  136. {
  137. setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
  138. return 1;
  139. }
  140. __setup("noxsaveopt", x86_xsaveopt_setup);
  141. #ifdef CONFIG_X86_32
  142. static int cachesize_override __cpuinitdata = -1;
  143. static int disable_x86_serial_nr __cpuinitdata = 1;
  144. static int __init cachesize_setup(char *str)
  145. {
  146. get_option(&str, &cachesize_override);
  147. return 1;
  148. }
  149. __setup("cachesize=", cachesize_setup);
  150. static int __init x86_fxsr_setup(char *s)
  151. {
  152. setup_clear_cpu_cap(X86_FEATURE_FXSR);
  153. setup_clear_cpu_cap(X86_FEATURE_XMM);
  154. return 1;
  155. }
  156. __setup("nofxsr", x86_fxsr_setup);
  157. static int __init x86_sep_setup(char *s)
  158. {
  159. setup_clear_cpu_cap(X86_FEATURE_SEP);
  160. return 1;
  161. }
  162. __setup("nosep", x86_sep_setup);
  163. /* Standard macro to see if a specific flag is changeable */
  164. static inline int flag_is_changeable_p(u32 flag)
  165. {
  166. u32 f1, f2;
  167. /*
  168. * Cyrix and IDT cpus allow disabling of CPUID
  169. * so the code below may return different results
  170. * when it is executed before and after enabling
  171. * the CPUID. Add "volatile" to not allow gcc to
  172. * optimize the subsequent calls to this function.
  173. */
  174. asm volatile ("pushfl \n\t"
  175. "pushfl \n\t"
  176. "popl %0 \n\t"
  177. "movl %0, %1 \n\t"
  178. "xorl %2, %0 \n\t"
  179. "pushl %0 \n\t"
  180. "popfl \n\t"
  181. "pushfl \n\t"
  182. "popl %0 \n\t"
  183. "popfl \n\t"
  184. : "=&r" (f1), "=&r" (f2)
  185. : "ir" (flag));
  186. return ((f1^f2) & flag) != 0;
  187. }
  188. /* Probe for the CPUID instruction */
  189. static int __cpuinit have_cpuid_p(void)
  190. {
  191. return flag_is_changeable_p(X86_EFLAGS_ID);
  192. }
  193. static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
  194. {
  195. unsigned long lo, hi;
  196. if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr)
  197. return;
  198. /* Disable processor serial number: */
  199. rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
  200. lo |= 0x200000;
  201. wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
  202. printk(KERN_NOTICE "CPU serial number disabled.\n");
  203. clear_cpu_cap(c, X86_FEATURE_PN);
  204. /* Disabling the serial number may affect the cpuid level */
  205. c->cpuid_level = cpuid_eax(0);
  206. }
  207. static int __init x86_serial_nr_setup(char *s)
  208. {
  209. disable_x86_serial_nr = 0;
  210. return 1;
  211. }
  212. __setup("serialnumber", x86_serial_nr_setup);
  213. #else
  214. static inline int flag_is_changeable_p(u32 flag)
  215. {
  216. return 1;
  217. }
  218. /* Probe for the CPUID instruction */
  219. static inline int have_cpuid_p(void)
  220. {
  221. return 1;
  222. }
  223. static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
  224. {
  225. }
  226. #endif
  227. /*
  228. * Some CPU features depend on higher CPUID levels, which may not always
  229. * be available due to CPUID level capping or broken virtualization
  230. * software. Add those features to this table to auto-disable them.
  231. */
  232. struct cpuid_dependent_feature {
  233. u32 feature;
  234. u32 level;
  235. };
  236. static const struct cpuid_dependent_feature __cpuinitconst
  237. cpuid_dependent_features[] = {
  238. { X86_FEATURE_MWAIT, 0x00000005 },
  239. { X86_FEATURE_DCA, 0x00000009 },
  240. { X86_FEATURE_XSAVE, 0x0000000d },
  241. { 0, 0 }
  242. };
  243. static void __cpuinit filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
  244. {
  245. const struct cpuid_dependent_feature *df;
  246. for (df = cpuid_dependent_features; df->feature; df++) {
  247. if (!cpu_has(c, df->feature))
  248. continue;
  249. /*
  250. * Note: cpuid_level is set to -1 if unavailable, but
  251. * extended_extended_level is set to 0 if unavailable
  252. * and the legitimate extended levels are all negative
  253. * when signed; hence the weird messing around with
  254. * signs here...
  255. */
  256. if (!((s32)df->level < 0 ?
  257. (u32)df->level > (u32)c->extended_cpuid_level :
  258. (s32)df->level > (s32)c->cpuid_level))
  259. continue;
  260. clear_cpu_cap(c, df->feature);
  261. if (!warn)
  262. continue;
  263. printk(KERN_WARNING
  264. "CPU: CPU feature %s disabled, no CPUID level 0x%x\n",
  265. x86_cap_flags[df->feature], df->level);
  266. }
  267. }
  268. /*
  269. * Naming convention should be: <Name> [(<Codename>)]
  270. * This table only is used unless init_<vendor>() below doesn't set it;
  271. * in particular, if CPUID levels 0x80000002..4 are supported, this
  272. * isn't used
  273. */
  274. /* Look up CPU names by table lookup. */
  275. static const char *__cpuinit table_lookup_model(struct cpuinfo_x86 *c)
  276. {
  277. const struct cpu_model_info *info;
  278. if (c->x86_model >= 16)
  279. return NULL; /* Range check */
  280. if (!this_cpu)
  281. return NULL;
  282. info = this_cpu->c_models;
  283. while (info && info->family) {
  284. if (info->family == c->x86)
  285. return info->model_names[c->x86_model];
  286. info++;
  287. }
  288. return NULL; /* Not found */
  289. }
  290. __u32 cpu_caps_cleared[NCAPINTS] __cpuinitdata;
  291. __u32 cpu_caps_set[NCAPINTS] __cpuinitdata;
  292. void load_percpu_segment(int cpu)
  293. {
  294. #ifdef CONFIG_X86_32
  295. loadsegment(fs, __KERNEL_PERCPU);
  296. #else
  297. loadsegment(gs, 0);
  298. wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
  299. #endif
  300. load_stack_canary_segment();
  301. }
  302. /*
  303. * Current gdt points %fs at the "master" per-cpu area: after this,
  304. * it's on the real one.
  305. */
  306. void switch_to_new_gdt(int cpu)
  307. {
  308. struct desc_ptr gdt_descr;
  309. gdt_descr.address = (long)get_cpu_gdt_table(cpu);
  310. gdt_descr.size = GDT_SIZE - 1;
  311. load_gdt(&gdt_descr);
  312. /* Reload the per-cpu base */
  313. load_percpu_segment(cpu);
  314. }
  315. static const struct cpu_dev *__cpuinitdata cpu_devs[X86_VENDOR_NUM] = {};
  316. static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
  317. {
  318. unsigned int *v;
  319. char *p, *q;
  320. if (c->extended_cpuid_level < 0x80000004)
  321. return;
  322. v = (unsigned int *)c->x86_model_id;
  323. cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
  324. cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
  325. cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
  326. c->x86_model_id[48] = 0;
  327. /*
  328. * Intel chips right-justify this string for some dumb reason;
  329. * undo that brain damage:
  330. */
  331. p = q = &c->x86_model_id[0];
  332. while (*p == ' ')
  333. p++;
  334. if (p != q) {
  335. while (*p)
  336. *q++ = *p++;
  337. while (q <= &c->x86_model_id[48])
  338. *q++ = '\0'; /* Zero-pad the rest */
  339. }
  340. }
  341. void __cpuinit cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
  342. {
  343. unsigned int n, dummy, ebx, ecx, edx, l2size;
  344. n = c->extended_cpuid_level;
  345. if (n >= 0x80000005) {
  346. cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
  347. c->x86_cache_size = (ecx>>24) + (edx>>24);
  348. #ifdef CONFIG_X86_64
  349. /* On K8 L1 TLB is inclusive, so don't count it */
  350. c->x86_tlbsize = 0;
  351. #endif
  352. }
  353. if (n < 0x80000006) /* Some chips just has a large L1. */
  354. return;
  355. cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
  356. l2size = ecx >> 16;
  357. #ifdef CONFIG_X86_64
  358. c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
  359. #else
  360. /* do processor-specific cache resizing */
  361. if (this_cpu->c_size_cache)
  362. l2size = this_cpu->c_size_cache(c, l2size);
  363. /* Allow user to override all this if necessary. */
  364. if (cachesize_override != -1)
  365. l2size = cachesize_override;
  366. if (l2size == 0)
  367. return; /* Again, no L2 cache is possible */
  368. #endif
  369. c->x86_cache_size = l2size;
  370. }
  371. void __cpuinit detect_ht(struct cpuinfo_x86 *c)
  372. {
  373. #ifdef CONFIG_X86_HT
  374. u32 eax, ebx, ecx, edx;
  375. int index_msb, core_bits;
  376. static bool printed;
  377. if (!cpu_has(c, X86_FEATURE_HT))
  378. return;
  379. if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
  380. goto out;
  381. if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
  382. return;
  383. cpuid(1, &eax, &ebx, &ecx, &edx);
  384. smp_num_siblings = (ebx & 0xff0000) >> 16;
  385. if (smp_num_siblings == 1) {
  386. printk_once(KERN_INFO "CPU0: Hyper-Threading is disabled\n");
  387. goto out;
  388. }
  389. if (smp_num_siblings <= 1)
  390. goto out;
  391. if (smp_num_siblings > nr_cpu_ids) {
  392. pr_warning("CPU: Unsupported number of siblings %d",
  393. smp_num_siblings);
  394. smp_num_siblings = 1;
  395. return;
  396. }
  397. index_msb = get_count_order(smp_num_siblings);
  398. c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
  399. smp_num_siblings = smp_num_siblings / c->x86_max_cores;
  400. index_msb = get_count_order(smp_num_siblings);
  401. core_bits = get_count_order(c->x86_max_cores);
  402. c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
  403. ((1 << core_bits) - 1);
  404. out:
  405. if (!printed && (c->x86_max_cores * smp_num_siblings) > 1) {
  406. printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
  407. c->phys_proc_id);
  408. printk(KERN_INFO "CPU: Processor Core ID: %d\n",
  409. c->cpu_core_id);
  410. printed = 1;
  411. }
  412. #endif
  413. }
  414. static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
  415. {
  416. char *v = c->x86_vendor_id;
  417. int i;
  418. for (i = 0; i < X86_VENDOR_NUM; i++) {
  419. if (!cpu_devs[i])
  420. break;
  421. if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
  422. (cpu_devs[i]->c_ident[1] &&
  423. !strcmp(v, cpu_devs[i]->c_ident[1]))) {
  424. this_cpu = cpu_devs[i];
  425. c->x86_vendor = this_cpu->c_x86_vendor;
  426. return;
  427. }
  428. }
  429. printk_once(KERN_ERR
  430. "CPU: vendor_id '%s' unknown, using generic init.\n" \
  431. "CPU: Your system may be unstable.\n", v);
  432. c->x86_vendor = X86_VENDOR_UNKNOWN;
  433. this_cpu = &default_cpu;
  434. }
  435. void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
  436. {
  437. /* Get vendor name */
  438. cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
  439. (unsigned int *)&c->x86_vendor_id[0],
  440. (unsigned int *)&c->x86_vendor_id[8],
  441. (unsigned int *)&c->x86_vendor_id[4]);
  442. c->x86 = 4;
  443. /* Intel-defined flags: level 0x00000001 */
  444. if (c->cpuid_level >= 0x00000001) {
  445. u32 junk, tfms, cap0, misc;
  446. cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
  447. c->x86 = (tfms >> 8) & 0xf;
  448. c->x86_model = (tfms >> 4) & 0xf;
  449. c->x86_mask = tfms & 0xf;
  450. if (c->x86 == 0xf)
  451. c->x86 += (tfms >> 20) & 0xff;
  452. if (c->x86 >= 0x6)
  453. c->x86_model += ((tfms >> 16) & 0xf) << 4;
  454. if (cap0 & (1<<19)) {
  455. c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
  456. c->x86_cache_alignment = c->x86_clflush_size;
  457. }
  458. }
  459. }
  460. static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
  461. {
  462. u32 tfms, xlvl;
  463. u32 ebx;
  464. /* Intel-defined flags: level 0x00000001 */
  465. if (c->cpuid_level >= 0x00000001) {
  466. u32 capability, excap;
  467. cpuid(0x00000001, &tfms, &ebx, &excap, &capability);
  468. c->x86_capability[0] = capability;
  469. c->x86_capability[4] = excap;
  470. }
  471. /* Additional Intel-defined flags: level 0x00000007 */
  472. if (c->cpuid_level >= 0x00000007) {
  473. u32 eax, ebx, ecx, edx;
  474. cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);
  475. if (eax > 0)
  476. c->x86_capability[9] = ebx;
  477. }
  478. /* AMD-defined flags: level 0x80000001 */
  479. xlvl = cpuid_eax(0x80000000);
  480. c->extended_cpuid_level = xlvl;
  481. if ((xlvl & 0xffff0000) == 0x80000000) {
  482. if (xlvl >= 0x80000001) {
  483. c->x86_capability[1] = cpuid_edx(0x80000001);
  484. c->x86_capability[6] = cpuid_ecx(0x80000001);
  485. }
  486. }
  487. if (c->extended_cpuid_level >= 0x80000008) {
  488. u32 eax = cpuid_eax(0x80000008);
  489. c->x86_virt_bits = (eax >> 8) & 0xff;
  490. c->x86_phys_bits = eax & 0xff;
  491. }
  492. #ifdef CONFIG_X86_32
  493. else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36))
  494. c->x86_phys_bits = 36;
  495. #endif
  496. if (c->extended_cpuid_level >= 0x80000007)
  497. c->x86_power = cpuid_edx(0x80000007);
  498. init_scattered_cpuid_features(c);
  499. }
  500. static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
  501. {
  502. #ifdef CONFIG_X86_32
  503. int i;
  504. /*
  505. * First of all, decide if this is a 486 or higher
  506. * It's a 486 if we can modify the AC flag
  507. */
  508. if (flag_is_changeable_p(X86_EFLAGS_AC))
  509. c->x86 = 4;
  510. else
  511. c->x86 = 3;
  512. for (i = 0; i < X86_VENDOR_NUM; i++)
  513. if (cpu_devs[i] && cpu_devs[i]->c_identify) {
  514. c->x86_vendor_id[0] = 0;
  515. cpu_devs[i]->c_identify(c);
  516. if (c->x86_vendor_id[0]) {
  517. get_cpu_vendor(c);
  518. break;
  519. }
  520. }
  521. #endif
  522. }
  523. /*
  524. * Do minimum CPU detection early.
  525. * Fields really needed: vendor, cpuid_level, family, model, mask,
  526. * cache alignment.
  527. * The others are not touched to avoid unwanted side effects.
  528. *
  529. * WARNING: this function is only called on the BP. Don't add code here
  530. * that is supposed to run on all CPUs.
  531. */
  532. static void __init early_identify_cpu(struct cpuinfo_x86 *c)
  533. {
  534. #ifdef CONFIG_X86_64
  535. c->x86_clflush_size = 64;
  536. c->x86_phys_bits = 36;
  537. c->x86_virt_bits = 48;
  538. #else
  539. c->x86_clflush_size = 32;
  540. c->x86_phys_bits = 32;
  541. c->x86_virt_bits = 32;
  542. #endif
  543. c->x86_cache_alignment = c->x86_clflush_size;
  544. memset(&c->x86_capability, 0, sizeof c->x86_capability);
  545. c->extended_cpuid_level = 0;
  546. if (!have_cpuid_p())
  547. identify_cpu_without_cpuid(c);
  548. /* cyrix could have cpuid enabled via c_identify()*/
  549. if (!have_cpuid_p())
  550. return;
  551. cpu_detect(c);
  552. get_cpu_vendor(c);
  553. get_cpu_cap(c);
  554. if (this_cpu->c_early_init)
  555. this_cpu->c_early_init(c);
  556. #ifdef CONFIG_SMP
  557. c->cpu_index = boot_cpu_id;
  558. #endif
  559. filter_cpuid_features(c, false);
  560. }
  561. void __init early_cpu_init(void)
  562. {
  563. const struct cpu_dev *const *cdev;
  564. int count = 0;
  565. #ifdef PROCESSOR_SELECT
  566. printk(KERN_INFO "KERNEL supported cpus:\n");
  567. #endif
  568. for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
  569. const struct cpu_dev *cpudev = *cdev;
  570. if (count >= X86_VENDOR_NUM)
  571. break;
  572. cpu_devs[count] = cpudev;
  573. count++;
  574. #ifdef PROCESSOR_SELECT
  575. {
  576. unsigned int j;
  577. for (j = 0; j < 2; j++) {
  578. if (!cpudev->c_ident[j])
  579. continue;
  580. printk(KERN_INFO " %s %s\n", cpudev->c_vendor,
  581. cpudev->c_ident[j]);
  582. }
  583. }
  584. #endif
  585. }
  586. early_identify_cpu(&boot_cpu_data);
  587. }
  588. /*
  589. * The NOPL instruction is supposed to exist on all CPUs with
  590. * family >= 6; unfortunately, that's not true in practice because
  591. * of early VIA chips and (more importantly) broken virtualizers that
  592. * are not easy to detect. In the latter case it doesn't even *fail*
  593. * reliably, so probing for it doesn't even work. Disable it completely
  594. * unless we can find a reliable way to detect all the broken cases.
  595. */
  596. static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
  597. {
  598. clear_cpu_cap(c, X86_FEATURE_NOPL);
  599. }
  600. static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
  601. {
  602. c->extended_cpuid_level = 0;
  603. if (!have_cpuid_p())
  604. identify_cpu_without_cpuid(c);
  605. /* cyrix could have cpuid enabled via c_identify()*/
  606. if (!have_cpuid_p())
  607. return;
  608. cpu_detect(c);
  609. get_cpu_vendor(c);
  610. get_cpu_cap(c);
  611. if (c->cpuid_level >= 0x00000001) {
  612. c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
  613. #ifdef CONFIG_X86_32
  614. # ifdef CONFIG_X86_HT
  615. c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
  616. # else
  617. c->apicid = c->initial_apicid;
  618. # endif
  619. #endif
  620. #ifdef CONFIG_X86_HT
  621. c->phys_proc_id = c->initial_apicid;
  622. #endif
  623. }
  624. get_model_name(c); /* Default name */
  625. detect_nopl(c);
  626. }
  627. /*
  628. * This does the hard work of actually picking apart the CPU stuff...
  629. */
  630. static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
  631. {
  632. int i;
  633. c->loops_per_jiffy = loops_per_jiffy;
  634. c->x86_cache_size = -1;
  635. c->x86_vendor = X86_VENDOR_UNKNOWN;
  636. c->x86_model = c->x86_mask = 0; /* So far unknown... */
  637. c->x86_vendor_id[0] = '\0'; /* Unset */
  638. c->x86_model_id[0] = '\0'; /* Unset */
  639. c->x86_max_cores = 1;
  640. c->x86_coreid_bits = 0;
  641. #ifdef CONFIG_X86_64
  642. c->x86_clflush_size = 64;
  643. c->x86_phys_bits = 36;
  644. c->x86_virt_bits = 48;
  645. #else
  646. c->cpuid_level = -1; /* CPUID not detected */
  647. c->x86_clflush_size = 32;
  648. c->x86_phys_bits = 32;
  649. c->x86_virt_bits = 32;
  650. #endif
  651. c->x86_cache_alignment = c->x86_clflush_size;
  652. memset(&c->x86_capability, 0, sizeof c->x86_capability);
  653. generic_identify(c);
  654. if (this_cpu->c_identify)
  655. this_cpu->c_identify(c);
  656. /* Clear/Set all flags overriden by options, after probe */
  657. for (i = 0; i < NCAPINTS; i++) {
  658. c->x86_capability[i] &= ~cpu_caps_cleared[i];
  659. c->x86_capability[i] |= cpu_caps_set[i];
  660. }
  661. #ifdef CONFIG_X86_64
  662. c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
  663. #endif
  664. /*
  665. * Vendor-specific initialization. In this section we
  666. * canonicalize the feature flags, meaning if there are
  667. * features a certain CPU supports which CPUID doesn't
  668. * tell us, CPUID claiming incorrect flags, or other bugs,
  669. * we handle them here.
  670. *
  671. * At the end of this section, c->x86_capability better
  672. * indicate the features this CPU genuinely supports!
  673. */
  674. if (this_cpu->c_init)
  675. this_cpu->c_init(c);
  676. /* Disable the PN if appropriate */
  677. squash_the_stupid_serial_number(c);
  678. /*
  679. * The vendor-specific functions might have changed features.
  680. * Now we do "generic changes."
  681. */
  682. /* Filter out anything that depends on CPUID levels we don't have */
  683. filter_cpuid_features(c, true);
  684. /* If the model name is still unset, do table lookup. */
  685. if (!c->x86_model_id[0]) {
  686. const char *p;
  687. p = table_lookup_model(c);
  688. if (p)
  689. strcpy(c->x86_model_id, p);
  690. else
  691. /* Last resort... */
  692. sprintf(c->x86_model_id, "%02x/%02x",
  693. c->x86, c->x86_model);
  694. }
  695. #ifdef CONFIG_X86_64
  696. detect_ht(c);
  697. #endif
  698. init_hypervisor(c);
  699. /*
  700. * Clear/Set all flags overriden by options, need do it
  701. * before following smp all cpus cap AND.
  702. */
  703. for (i = 0; i < NCAPINTS; i++) {
  704. c->x86_capability[i] &= ~cpu_caps_cleared[i];
  705. c->x86_capability[i] |= cpu_caps_set[i];
  706. }
  707. /*
  708. * On SMP, boot_cpu_data holds the common feature set between
  709. * all CPUs; so make sure that we indicate which features are
  710. * common between the CPUs. The first time this routine gets
  711. * executed, c == &boot_cpu_data.
  712. */
  713. if (c != &boot_cpu_data) {
  714. /* AND the already accumulated flags with these */
  715. for (i = 0; i < NCAPINTS; i++)
  716. boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
  717. }
  718. /* Init Machine Check Exception if available. */
  719. mcheck_cpu_init(c);
  720. select_idle_routine(c);
  721. #if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
  722. numa_add_cpu(smp_processor_id());
  723. #endif
  724. }
  725. #ifdef CONFIG_X86_64
  726. static void vgetcpu_set_mode(void)
  727. {
  728. if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
  729. vgetcpu_mode = VGETCPU_RDTSCP;
  730. else
  731. vgetcpu_mode = VGETCPU_LSL;
  732. }
  733. #endif
  734. void __init identify_boot_cpu(void)
  735. {
  736. identify_cpu(&boot_cpu_data);
  737. init_c1e_mask();
  738. #ifdef CONFIG_X86_32
  739. sysenter_setup();
  740. enable_sep_cpu();
  741. #else
  742. vgetcpu_set_mode();
  743. #endif
  744. init_hw_perf_events();
  745. }
  746. void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
  747. {
  748. BUG_ON(c == &boot_cpu_data);
  749. identify_cpu(c);
  750. #ifdef CONFIG_X86_32
  751. enable_sep_cpu();
  752. #endif
  753. mtrr_ap_init();
  754. }
  755. struct msr_range {
  756. unsigned min;
  757. unsigned max;
  758. };
  759. static const struct msr_range msr_range_array[] __cpuinitconst = {
  760. { 0x00000000, 0x00000418},
  761. { 0xc0000000, 0xc000040b},
  762. { 0xc0010000, 0xc0010142},
  763. { 0xc0011000, 0xc001103b},
  764. };
  765. static void __cpuinit print_cpu_msr(void)
  766. {
  767. unsigned index_min, index_max;
  768. unsigned index;
  769. u64 val;
  770. int i;
  771. for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
  772. index_min = msr_range_array[i].min;
  773. index_max = msr_range_array[i].max;
  774. for (index = index_min; index < index_max; index++) {
  775. if (rdmsrl_amd_safe(index, &val))
  776. continue;
  777. printk(KERN_INFO " MSR%08x: %016llx\n", index, val);
  778. }
  779. }
  780. }
  781. static int show_msr __cpuinitdata;
  782. static __init int setup_show_msr(char *arg)
  783. {
  784. int num;
  785. get_option(&arg, &num);
  786. if (num > 0)
  787. show_msr = num;
  788. return 1;
  789. }
  790. __setup("show_msr=", setup_show_msr);
  791. static __init int setup_noclflush(char *arg)
  792. {
  793. setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
  794. return 1;
  795. }
  796. __setup("noclflush", setup_noclflush);
  797. void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
  798. {
  799. const char *vendor = NULL;
  800. if (c->x86_vendor < X86_VENDOR_NUM) {
  801. vendor = this_cpu->c_vendor;
  802. } else {
  803. if (c->cpuid_level >= 0)
  804. vendor = c->x86_vendor_id;
  805. }
  806. if (vendor && !strstr(c->x86_model_id, vendor))
  807. printk(KERN_CONT "%s ", vendor);
  808. if (c->x86_model_id[0])
  809. printk(KERN_CONT "%s", c->x86_model_id);
  810. else
  811. printk(KERN_CONT "%d86", c->x86);
  812. if (c->x86_mask || c->cpuid_level >= 0)
  813. printk(KERN_CONT " stepping %02x\n", c->x86_mask);
  814. else
  815. printk(KERN_CONT "\n");
  816. #ifdef CONFIG_SMP
  817. if (c->cpu_index < show_msr)
  818. print_cpu_msr();
  819. #else
  820. if (show_msr)
  821. print_cpu_msr();
  822. #endif
  823. }
  824. static __init int setup_disablecpuid(char *arg)
  825. {
  826. int bit;
  827. if (get_option(&arg, &bit) && bit < NCAPINTS*32)
  828. setup_clear_cpu_cap(bit);
  829. else
  830. return 0;
  831. return 1;
  832. }
  833. __setup("clearcpuid=", setup_disablecpuid);
  834. #ifdef CONFIG_X86_64
  835. struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table };
  836. DEFINE_PER_CPU_FIRST(union irq_stack_union,
  837. irq_stack_union) __aligned(PAGE_SIZE);
  838. /*
  839. * The following four percpu variables are hot. Align current_task to
  840. * cacheline size such that all four fall in the same cacheline.
  841. */
  842. DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
  843. &init_task;
  844. EXPORT_PER_CPU_SYMBOL(current_task);
  845. DEFINE_PER_CPU(unsigned long, kernel_stack) =
  846. (unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
  847. EXPORT_PER_CPU_SYMBOL(kernel_stack);
  848. DEFINE_PER_CPU(char *, irq_stack_ptr) =
  849. init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
  850. DEFINE_PER_CPU(unsigned int, irq_count) = -1;
  851. /*
  852. * Special IST stacks which the CPU switches to when it calls
  853. * an IST-marked descriptor entry. Up to 7 stacks (hardware
  854. * limit), all of them are 4K, except the debug stack which
  855. * is 8K.
  856. */
  857. static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
  858. [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
  859. [DEBUG_STACK - 1] = DEBUG_STKSZ
  860. };
  861. static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
  862. [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
  863. /* May not be marked __init: used by software suspend */
  864. void syscall_init(void)
  865. {
  866. /*
  867. * LSTAR and STAR live in a bit strange symbiosis.
  868. * They both write to the same internal register. STAR allows to
  869. * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
  870. */
  871. wrmsrl(MSR_STAR, ((u64)__USER32_CS)<<48 | ((u64)__KERNEL_CS)<<32);
  872. wrmsrl(MSR_LSTAR, system_call);
  873. wrmsrl(MSR_CSTAR, ignore_sysret);
  874. #ifdef CONFIG_IA32_EMULATION
  875. syscall32_cpu_init();
  876. #endif
  877. /* Flags to clear on syscall */
  878. wrmsrl(MSR_SYSCALL_MASK,
  879. X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
  880. }
  881. unsigned long kernel_eflags;
  882. /*
  883. * Copies of the original ist values from the tss are only accessed during
  884. * debugging, no special alignment required.
  885. */
  886. DEFINE_PER_CPU(struct orig_ist, orig_ist);
  887. #else /* CONFIG_X86_64 */
  888. DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
  889. EXPORT_PER_CPU_SYMBOL(current_task);
  890. #ifdef CONFIG_CC_STACKPROTECTOR
  891. DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
  892. #endif
  893. /* Make sure %fs and %gs are initialized properly in idle threads */
  894. struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
  895. {
  896. memset(regs, 0, sizeof(struct pt_regs));
  897. regs->fs = __KERNEL_PERCPU;
  898. regs->gs = __KERNEL_STACK_CANARY;
  899. return regs;
  900. }
  901. #endif /* CONFIG_X86_64 */
  902. /*
  903. * Clear all 6 debug registers:
  904. */
  905. static void clear_all_debug_regs(void)
  906. {
  907. int i;
  908. for (i = 0; i < 8; i++) {
  909. /* Ignore db4, db5 */
  910. if ((i == 4) || (i == 5))
  911. continue;
  912. set_debugreg(0, i);
  913. }
  914. }
  915. #ifdef CONFIG_KGDB
  916. /*
  917. * Restore debug regs if using kgdbwait and you have a kernel debugger
  918. * connection established.
  919. */
  920. static void dbg_restore_debug_regs(void)
  921. {
  922. if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break))
  923. arch_kgdb_ops.correct_hw_break();
  924. }
  925. #else /* ! CONFIG_KGDB */
  926. #define dbg_restore_debug_regs()
  927. #endif /* ! CONFIG_KGDB */
  928. /*
  929. * cpu_init() initializes state that is per-CPU. Some data is already
  930. * initialized (naturally) in the bootstrap process, such as the GDT
  931. * and IDT. We reload them nevertheless, this function acts as a
  932. * 'CPU state barrier', nothing should get across.
  933. * A lot of state is already set up in PDA init for 64 bit
  934. */
  935. #ifdef CONFIG_X86_64
  936. void __cpuinit cpu_init(void)
  937. {
  938. struct orig_ist *oist;
  939. struct task_struct *me;
  940. struct tss_struct *t;
  941. unsigned long v;
  942. int cpu;
  943. int i;
  944. cpu = stack_smp_processor_id();
  945. t = &per_cpu(init_tss, cpu);
  946. oist = &per_cpu(orig_ist, cpu);
  947. #ifdef CONFIG_NUMA
  948. if (cpu != 0 && percpu_read(numa_node) == 0 &&
  949. early_cpu_to_node(cpu) != NUMA_NO_NODE)
  950. set_numa_node(early_cpu_to_node(cpu));
  951. #endif
  952. me = current;
  953. if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask))
  954. panic("CPU#%d already initialized!\n", cpu);
  955. pr_debug("Initializing CPU#%d\n", cpu);
  956. clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
  957. /*
  958. * Initialize the per-CPU GDT with the boot GDT,
  959. * and set up the GDT descriptor:
  960. */
  961. switch_to_new_gdt(cpu);
  962. loadsegment(fs, 0);
  963. load_idt((const struct desc_ptr *)&idt_descr);
  964. memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
  965. syscall_init();
  966. wrmsrl(MSR_FS_BASE, 0);
  967. wrmsrl(MSR_KERNEL_GS_BASE, 0);
  968. barrier();
  969. x86_configure_nx();
  970. if (cpu != 0)
  971. enable_x2apic();
  972. /*
  973. * set up and load the per-CPU TSS
  974. */
  975. if (!oist->ist[0]) {
  976. char *estacks = per_cpu(exception_stacks, cpu);
  977. for (v = 0; v < N_EXCEPTION_STACKS; v++) {
  978. estacks += exception_stack_sizes[v];
  979. oist->ist[v] = t->x86_tss.ist[v] =
  980. (unsigned long)estacks;
  981. }
  982. }
  983. t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
  984. /*
  985. * <= is required because the CPU will access up to
  986. * 8 bits beyond the end of the IO permission bitmap.
  987. */
  988. for (i = 0; i <= IO_BITMAP_LONGS; i++)
  989. t->io_bitmap[i] = ~0UL;
  990. atomic_inc(&init_mm.mm_count);
  991. me->active_mm = &init_mm;
  992. BUG_ON(me->mm);
  993. enter_lazy_tlb(&init_mm, me);
  994. load_sp0(t, &current->thread);
  995. set_tss_desc(cpu, t);
  996. load_TR_desc();
  997. load_LDT(&init_mm.context);
  998. clear_all_debug_regs();
  999. dbg_restore_debug_regs();
  1000. fpu_init();
  1001. xsave_init();
  1002. raw_local_save_flags(kernel_eflags);
  1003. if (is_uv_system())
  1004. uv_cpu_init();
  1005. }
  1006. #else
  1007. void __cpuinit cpu_init(void)
  1008. {
  1009. int cpu = smp_processor_id();
  1010. struct task_struct *curr = current;
  1011. struct tss_struct *t = &per_cpu(init_tss, cpu);
  1012. struct thread_struct *thread = &curr->thread;
  1013. if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)) {
  1014. printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
  1015. for (;;)
  1016. local_irq_enable();
  1017. }
  1018. printk(KERN_INFO "Initializing CPU#%d\n", cpu);
  1019. if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
  1020. clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
  1021. load_idt(&idt_descr);
  1022. switch_to_new_gdt(cpu);
  1023. /*
  1024. * Set up and load the per-CPU TSS and LDT
  1025. */
  1026. atomic_inc(&init_mm.mm_count);
  1027. curr->active_mm = &init_mm;
  1028. BUG_ON(curr->mm);
  1029. enter_lazy_tlb(&init_mm, curr);
  1030. load_sp0(t, thread);
  1031. set_tss_desc(cpu, t);
  1032. load_TR_desc();
  1033. load_LDT(&init_mm.context);
  1034. t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
  1035. #ifdef CONFIG_DOUBLEFAULT
  1036. /* Set up doublefault TSS pointer in the GDT */
  1037. __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
  1038. #endif
  1039. clear_all_debug_regs();
  1040. dbg_restore_debug_regs();
  1041. /*
  1042. * Force FPU initialization:
  1043. */
  1044. current_thread_info()->status = 0;
  1045. clear_used_math();
  1046. mxcsr_feature_mask_init();
  1047. fpu_init();
  1048. xsave_init();
  1049. }
  1050. #endif