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, ¤t->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