Loading...
1#include <linux/bootmem.h>
2#include <linux/linkage.h>
3#include <linux/bitops.h>
4#include <linux/kernel.h>
5#include <linux/export.h>
6#include <linux/percpu.h>
7#include <linux/string.h>
8#include <linux/ctype.h>
9#include <linux/delay.h>
10#include <linux/sched/mm.h>
11#include <linux/sched/clock.h>
12#include <linux/sched/task.h>
13#include <linux/init.h>
14#include <linux/kprobes.h>
15#include <linux/kgdb.h>
16#include <linux/smp.h>
17#include <linux/io.h>
18#include <linux/syscore_ops.h>
19
20#include <asm/stackprotector.h>
21#include <asm/perf_event.h>
22#include <asm/mmu_context.h>
23#include <asm/archrandom.h>
24#include <asm/hypervisor.h>
25#include <asm/processor.h>
26#include <asm/tlbflush.h>
27#include <asm/debugreg.h>
28#include <asm/sections.h>
29#include <asm/vsyscall.h>
30#include <linux/topology.h>
31#include <linux/cpumask.h>
32#include <asm/pgtable.h>
33#include <linux/atomic.h>
34#include <asm/proto.h>
35#include <asm/setup.h>
36#include <asm/apic.h>
37#include <asm/desc.h>
38#include <asm/fpu/internal.h>
39#include <asm/mtrr.h>
40#include <asm/hwcap2.h>
41#include <linux/numa.h>
42#include <asm/asm.h>
43#include <asm/bugs.h>
44#include <asm/cpu.h>
45#include <asm/mce.h>
46#include <asm/msr.h>
47#include <asm/pat.h>
48#include <asm/microcode.h>
49#include <asm/microcode_intel.h>
50#include <asm/intel-family.h>
51#include <asm/cpu_device_id.h>
52
53#ifdef CONFIG_X86_LOCAL_APIC
54#include <asm/uv/uv.h>
55#endif
56
57#include "cpu.h"
58
59u32 elf_hwcap2 __read_mostly;
60
61/* all of these masks are initialized in setup_cpu_local_masks() */
62cpumask_var_t cpu_initialized_mask;
63cpumask_var_t cpu_callout_mask;
64cpumask_var_t cpu_callin_mask;
65
66/* representing cpus for which sibling maps can be computed */
67cpumask_var_t cpu_sibling_setup_mask;
68
69/* correctly size the local cpu masks */
70void __init setup_cpu_local_masks(void)
71{
72 alloc_bootmem_cpumask_var(&cpu_initialized_mask);
73 alloc_bootmem_cpumask_var(&cpu_callin_mask);
74 alloc_bootmem_cpumask_var(&cpu_callout_mask);
75 alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
76}
77
78static void default_init(struct cpuinfo_x86 *c)
79{
80#ifdef CONFIG_X86_64
81 cpu_detect_cache_sizes(c);
82#else
83 /* Not much we can do here... */
84 /* Check if at least it has cpuid */
85 if (c->cpuid_level == -1) {
86 /* No cpuid. It must be an ancient CPU */
87 if (c->x86 == 4)
88 strcpy(c->x86_model_id, "486");
89 else if (c->x86 == 3)
90 strcpy(c->x86_model_id, "386");
91 }
92#endif
93}
94
95static const struct cpu_dev default_cpu = {
96 .c_init = default_init,
97 .c_vendor = "Unknown",
98 .c_x86_vendor = X86_VENDOR_UNKNOWN,
99};
100
101static const struct cpu_dev *this_cpu = &default_cpu;
102
103DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
104#ifdef CONFIG_X86_64
105 /*
106 * We need valid kernel segments for data and code in long mode too
107 * IRET will check the segment types kkeil 2000/10/28
108 * Also sysret mandates a special GDT layout
109 *
110 * TLS descriptors are currently at a different place compared to i386.
111 * Hopefully nobody expects them at a fixed place (Wine?)
112 */
113 [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
114 [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
115 [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
116 [GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff),
117 [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff),
118 [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff),
119#else
120 [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff),
121 [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
122 [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff),
123 [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff),
124 /*
125 * Segments used for calling PnP BIOS have byte granularity.
126 * They code segments and data segments have fixed 64k limits,
127 * the transfer segment sizes are set at run time.
128 */
129 /* 32-bit code */
130 [GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
131 /* 16-bit code */
132 [GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
133 /* 16-bit data */
134 [GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(0x0092, 0, 0xffff),
135 /* 16-bit data */
136 [GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(0x0092, 0, 0),
137 /* 16-bit data */
138 [GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(0x0092, 0, 0),
139 /*
140 * The APM segments have byte granularity and their bases
141 * are set at run time. All have 64k limits.
142 */
143 /* 32-bit code */
144 [GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
145 /* 16-bit code */
146 [GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
147 /* data */
148 [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff),
149
150 [GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
151 [GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
152 GDT_STACK_CANARY_INIT
153#endif
154} };
155EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
156
157static int __init x86_mpx_setup(char *s)
158{
159 /* require an exact match without trailing characters */
160 if (strlen(s))
161 return 0;
162
163 /* do not emit a message if the feature is not present */
164 if (!boot_cpu_has(X86_FEATURE_MPX))
165 return 1;
166
167 setup_clear_cpu_cap(X86_FEATURE_MPX);
168 pr_info("nompx: Intel Memory Protection Extensions (MPX) disabled\n");
169 return 1;
170}
171__setup("nompx", x86_mpx_setup);
172
173#ifdef CONFIG_X86_64
174static int __init x86_nopcid_setup(char *s)
175{
176 /* nopcid doesn't accept parameters */
177 if (s)
178 return -EINVAL;
179
180 /* do not emit a message if the feature is not present */
181 if (!boot_cpu_has(X86_FEATURE_PCID))
182 return 0;
183
184 setup_clear_cpu_cap(X86_FEATURE_PCID);
185 pr_info("nopcid: PCID feature disabled\n");
186 return 0;
187}
188early_param("nopcid", x86_nopcid_setup);
189#endif
190
191static int __init x86_noinvpcid_setup(char *s)
192{
193 /* noinvpcid doesn't accept parameters */
194 if (s)
195 return -EINVAL;
196
197 /* do not emit a message if the feature is not present */
198 if (!boot_cpu_has(X86_FEATURE_INVPCID))
199 return 0;
200
201 setup_clear_cpu_cap(X86_FEATURE_INVPCID);
202 pr_info("noinvpcid: INVPCID feature disabled\n");
203 return 0;
204}
205early_param("noinvpcid", x86_noinvpcid_setup);
206
207#ifdef CONFIG_X86_32
208static int cachesize_override = -1;
209static int disable_x86_serial_nr = 1;
210
211static int __init cachesize_setup(char *str)
212{
213 get_option(&str, &cachesize_override);
214 return 1;
215}
216__setup("cachesize=", cachesize_setup);
217
218static int __init x86_sep_setup(char *s)
219{
220 setup_clear_cpu_cap(X86_FEATURE_SEP);
221 return 1;
222}
223__setup("nosep", x86_sep_setup);
224
225/* Standard macro to see if a specific flag is changeable */
226static inline int flag_is_changeable_p(u32 flag)
227{
228 u32 f1, f2;
229
230 /*
231 * Cyrix and IDT cpus allow disabling of CPUID
232 * so the code below may return different results
233 * when it is executed before and after enabling
234 * the CPUID. Add "volatile" to not allow gcc to
235 * optimize the subsequent calls to this function.
236 */
237 asm volatile ("pushfl \n\t"
238 "pushfl \n\t"
239 "popl %0 \n\t"
240 "movl %0, %1 \n\t"
241 "xorl %2, %0 \n\t"
242 "pushl %0 \n\t"
243 "popfl \n\t"
244 "pushfl \n\t"
245 "popl %0 \n\t"
246 "popfl \n\t"
247
248 : "=&r" (f1), "=&r" (f2)
249 : "ir" (flag));
250
251 return ((f1^f2) & flag) != 0;
252}
253
254/* Probe for the CPUID instruction */
255int have_cpuid_p(void)
256{
257 return flag_is_changeable_p(X86_EFLAGS_ID);
258}
259
260static void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
261{
262 unsigned long lo, hi;
263
264 if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr)
265 return;
266
267 /* Disable processor serial number: */
268
269 rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
270 lo |= 0x200000;
271 wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
272
273 pr_notice("CPU serial number disabled.\n");
274 clear_cpu_cap(c, X86_FEATURE_PN);
275
276 /* Disabling the serial number may affect the cpuid level */
277 c->cpuid_level = cpuid_eax(0);
278}
279
280static int __init x86_serial_nr_setup(char *s)
281{
282 disable_x86_serial_nr = 0;
283 return 1;
284}
285__setup("serialnumber", x86_serial_nr_setup);
286#else
287static inline int flag_is_changeable_p(u32 flag)
288{
289 return 1;
290}
291static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
292{
293}
294#endif
295
296static __init int setup_disable_smep(char *arg)
297{
298 setup_clear_cpu_cap(X86_FEATURE_SMEP);
299 /* Check for things that depend on SMEP being enabled: */
300 check_mpx_erratum(&boot_cpu_data);
301 return 1;
302}
303__setup("nosmep", setup_disable_smep);
304
305static __always_inline void setup_smep(struct cpuinfo_x86 *c)
306{
307 if (cpu_has(c, X86_FEATURE_SMEP))
308 cr4_set_bits(X86_CR4_SMEP);
309}
310
311static __init int setup_disable_smap(char *arg)
312{
313 setup_clear_cpu_cap(X86_FEATURE_SMAP);
314 return 1;
315}
316__setup("nosmap", setup_disable_smap);
317
318static __always_inline void setup_smap(struct cpuinfo_x86 *c)
319{
320 unsigned long eflags = native_save_fl();
321
322 /* This should have been cleared long ago */
323 BUG_ON(eflags & X86_EFLAGS_AC);
324
325 if (cpu_has(c, X86_FEATURE_SMAP)) {
326#ifdef CONFIG_X86_SMAP
327 cr4_set_bits(X86_CR4_SMAP);
328#else
329 cr4_clear_bits(X86_CR4_SMAP);
330#endif
331 }
332}
333
334static __always_inline void setup_umip(struct cpuinfo_x86 *c)
335{
336 /* Check the boot processor, plus build option for UMIP. */
337 if (!cpu_feature_enabled(X86_FEATURE_UMIP))
338 goto out;
339
340 /* Check the current processor's cpuid bits. */
341 if (!cpu_has(c, X86_FEATURE_UMIP))
342 goto out;
343
344 cr4_set_bits(X86_CR4_UMIP);
345
346 pr_info("x86/cpu: Activated the Intel User Mode Instruction Prevention (UMIP) CPU feature\n");
347
348 return;
349
350out:
351 /*
352 * Make sure UMIP is disabled in case it was enabled in a
353 * previous boot (e.g., via kexec).
354 */
355 cr4_clear_bits(X86_CR4_UMIP);
356}
357
358/*
359 * Protection Keys are not available in 32-bit mode.
360 */
361static bool pku_disabled;
362
363static __always_inline void setup_pku(struct cpuinfo_x86 *c)
364{
365 /* check the boot processor, plus compile options for PKU: */
366 if (!cpu_feature_enabled(X86_FEATURE_PKU))
367 return;
368 /* checks the actual processor's cpuid bits: */
369 if (!cpu_has(c, X86_FEATURE_PKU))
370 return;
371 if (pku_disabled)
372 return;
373
374 cr4_set_bits(X86_CR4_PKE);
375 /*
376 * Seting X86_CR4_PKE will cause the X86_FEATURE_OSPKE
377 * cpuid bit to be set. We need to ensure that we
378 * update that bit in this CPU's "cpu_info".
379 */
380 get_cpu_cap(c);
381}
382
383#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
384static __init int setup_disable_pku(char *arg)
385{
386 /*
387 * Do not clear the X86_FEATURE_PKU bit. All of the
388 * runtime checks are against OSPKE so clearing the
389 * bit does nothing.
390 *
391 * This way, we will see "pku" in cpuinfo, but not
392 * "ospke", which is exactly what we want. It shows
393 * that the CPU has PKU, but the OS has not enabled it.
394 * This happens to be exactly how a system would look
395 * if we disabled the config option.
396 */
397 pr_info("x86: 'nopku' specified, disabling Memory Protection Keys\n");
398 pku_disabled = true;
399 return 1;
400}
401__setup("nopku", setup_disable_pku);
402#endif /* CONFIG_X86_64 */
403
404/*
405 * Some CPU features depend on higher CPUID levels, which may not always
406 * be available due to CPUID level capping or broken virtualization
407 * software. Add those features to this table to auto-disable them.
408 */
409struct cpuid_dependent_feature {
410 u32 feature;
411 u32 level;
412};
413
414static const struct cpuid_dependent_feature
415cpuid_dependent_features[] = {
416 { X86_FEATURE_MWAIT, 0x00000005 },
417 { X86_FEATURE_DCA, 0x00000009 },
418 { X86_FEATURE_XSAVE, 0x0000000d },
419 { 0, 0 }
420};
421
422static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
423{
424 const struct cpuid_dependent_feature *df;
425
426 for (df = cpuid_dependent_features; df->feature; df++) {
427
428 if (!cpu_has(c, df->feature))
429 continue;
430 /*
431 * Note: cpuid_level is set to -1 if unavailable, but
432 * extended_extended_level is set to 0 if unavailable
433 * and the legitimate extended levels are all negative
434 * when signed; hence the weird messing around with
435 * signs here...
436 */
437 if (!((s32)df->level < 0 ?
438 (u32)df->level > (u32)c->extended_cpuid_level :
439 (s32)df->level > (s32)c->cpuid_level))
440 continue;
441
442 clear_cpu_cap(c, df->feature);
443 if (!warn)
444 continue;
445
446 pr_warn("CPU: CPU feature " X86_CAP_FMT " disabled, no CPUID level 0x%x\n",
447 x86_cap_flag(df->feature), df->level);
448 }
449}
450
451/*
452 * Naming convention should be: <Name> [(<Codename>)]
453 * This table only is used unless init_<vendor>() below doesn't set it;
454 * in particular, if CPUID levels 0x80000002..4 are supported, this
455 * isn't used
456 */
457
458/* Look up CPU names by table lookup. */
459static const char *table_lookup_model(struct cpuinfo_x86 *c)
460{
461#ifdef CONFIG_X86_32
462 const struct legacy_cpu_model_info *info;
463
464 if (c->x86_model >= 16)
465 return NULL; /* Range check */
466
467 if (!this_cpu)
468 return NULL;
469
470 info = this_cpu->legacy_models;
471
472 while (info->family) {
473 if (info->family == c->x86)
474 return info->model_names[c->x86_model];
475 info++;
476 }
477#endif
478 return NULL; /* Not found */
479}
480
481__u32 cpu_caps_cleared[NCAPINTS + NBUGINTS];
482__u32 cpu_caps_set[NCAPINTS + NBUGINTS];
483
484void load_percpu_segment(int cpu)
485{
486#ifdef CONFIG_X86_32
487 loadsegment(fs, __KERNEL_PERCPU);
488#else
489 __loadsegment_simple(gs, 0);
490 wrmsrl(MSR_GS_BASE, cpu_kernelmode_gs_base(cpu));
491#endif
492 load_stack_canary_segment();
493}
494
495#ifdef CONFIG_X86_32
496/* The 32-bit entry code needs to find cpu_entry_area. */
497DEFINE_PER_CPU(struct cpu_entry_area *, cpu_entry_area);
498#endif
499
500#ifdef CONFIG_X86_64
501/*
502 * Special IST stacks which the CPU switches to when it calls
503 * an IST-marked descriptor entry. Up to 7 stacks (hardware
504 * limit), all of them are 4K, except the debug stack which
505 * is 8K.
506 */
507static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
508 [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
509 [DEBUG_STACK - 1] = DEBUG_STKSZ
510};
511#endif
512
513/* Load the original GDT from the per-cpu structure */
514void load_direct_gdt(int cpu)
515{
516 struct desc_ptr gdt_descr;
517
518 gdt_descr.address = (long)get_cpu_gdt_rw(cpu);
519 gdt_descr.size = GDT_SIZE - 1;
520 load_gdt(&gdt_descr);
521}
522EXPORT_SYMBOL_GPL(load_direct_gdt);
523
524/* Load a fixmap remapping of the per-cpu GDT */
525void load_fixmap_gdt(int cpu)
526{
527 struct desc_ptr gdt_descr;
528
529 gdt_descr.address = (long)get_cpu_gdt_ro(cpu);
530 gdt_descr.size = GDT_SIZE - 1;
531 load_gdt(&gdt_descr);
532}
533EXPORT_SYMBOL_GPL(load_fixmap_gdt);
534
535/*
536 * Current gdt points %fs at the "master" per-cpu area: after this,
537 * it's on the real one.
538 */
539void switch_to_new_gdt(int cpu)
540{
541 /* Load the original GDT */
542 load_direct_gdt(cpu);
543 /* Reload the per-cpu base */
544 load_percpu_segment(cpu);
545}
546
547static const struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
548
549static void get_model_name(struct cpuinfo_x86 *c)
550{
551 unsigned int *v;
552 char *p, *q, *s;
553
554 if (c->extended_cpuid_level < 0x80000004)
555 return;
556
557 v = (unsigned int *)c->x86_model_id;
558 cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
559 cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
560 cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
561 c->x86_model_id[48] = 0;
562
563 /* Trim whitespace */
564 p = q = s = &c->x86_model_id[0];
565
566 while (*p == ' ')
567 p++;
568
569 while (*p) {
570 /* Note the last non-whitespace index */
571 if (!isspace(*p))
572 s = q;
573
574 *q++ = *p++;
575 }
576
577 *(s + 1) = '\0';
578}
579
580void cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
581{
582 unsigned int n, dummy, ebx, ecx, edx, l2size;
583
584 n = c->extended_cpuid_level;
585
586 if (n >= 0x80000005) {
587 cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
588 c->x86_cache_size = (ecx>>24) + (edx>>24);
589#ifdef CONFIG_X86_64
590 /* On K8 L1 TLB is inclusive, so don't count it */
591 c->x86_tlbsize = 0;
592#endif
593 }
594
595 if (n < 0x80000006) /* Some chips just has a large L1. */
596 return;
597
598 cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
599 l2size = ecx >> 16;
600
601#ifdef CONFIG_X86_64
602 c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
603#else
604 /* do processor-specific cache resizing */
605 if (this_cpu->legacy_cache_size)
606 l2size = this_cpu->legacy_cache_size(c, l2size);
607
608 /* Allow user to override all this if necessary. */
609 if (cachesize_override != -1)
610 l2size = cachesize_override;
611
612 if (l2size == 0)
613 return; /* Again, no L2 cache is possible */
614#endif
615
616 c->x86_cache_size = l2size;
617}
618
619u16 __read_mostly tlb_lli_4k[NR_INFO];
620u16 __read_mostly tlb_lli_2m[NR_INFO];
621u16 __read_mostly tlb_lli_4m[NR_INFO];
622u16 __read_mostly tlb_lld_4k[NR_INFO];
623u16 __read_mostly tlb_lld_2m[NR_INFO];
624u16 __read_mostly tlb_lld_4m[NR_INFO];
625u16 __read_mostly tlb_lld_1g[NR_INFO];
626
627static void cpu_detect_tlb(struct cpuinfo_x86 *c)
628{
629 if (this_cpu->c_detect_tlb)
630 this_cpu->c_detect_tlb(c);
631
632 pr_info("Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n",
633 tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES],
634 tlb_lli_4m[ENTRIES]);
635
636 pr_info("Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d, 1GB %d\n",
637 tlb_lld_4k[ENTRIES], tlb_lld_2m[ENTRIES],
638 tlb_lld_4m[ENTRIES], tlb_lld_1g[ENTRIES]);
639}
640
641void detect_ht(struct cpuinfo_x86 *c)
642{
643#ifdef CONFIG_SMP
644 u32 eax, ebx, ecx, edx;
645 int index_msb, core_bits;
646 static bool printed;
647
648 if (!cpu_has(c, X86_FEATURE_HT))
649 return;
650
651 if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
652 goto out;
653
654 if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
655 return;
656
657 cpuid(1, &eax, &ebx, &ecx, &edx);
658
659 smp_num_siblings = (ebx & 0xff0000) >> 16;
660
661 if (smp_num_siblings == 1) {
662 pr_info_once("CPU0: Hyper-Threading is disabled\n");
663 goto out;
664 }
665
666 if (smp_num_siblings <= 1)
667 goto out;
668
669 index_msb = get_count_order(smp_num_siblings);
670 c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
671
672 smp_num_siblings = smp_num_siblings / c->x86_max_cores;
673
674 index_msb = get_count_order(smp_num_siblings);
675
676 core_bits = get_count_order(c->x86_max_cores);
677
678 c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
679 ((1 << core_bits) - 1);
680
681out:
682 if (!printed && (c->x86_max_cores * smp_num_siblings) > 1) {
683 pr_info("CPU: Physical Processor ID: %d\n",
684 c->phys_proc_id);
685 pr_info("CPU: Processor Core ID: %d\n",
686 c->cpu_core_id);
687 printed = 1;
688 }
689#endif
690}
691
692static void get_cpu_vendor(struct cpuinfo_x86 *c)
693{
694 char *v = c->x86_vendor_id;
695 int i;
696
697 for (i = 0; i < X86_VENDOR_NUM; i++) {
698 if (!cpu_devs[i])
699 break;
700
701 if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
702 (cpu_devs[i]->c_ident[1] &&
703 !strcmp(v, cpu_devs[i]->c_ident[1]))) {
704
705 this_cpu = cpu_devs[i];
706 c->x86_vendor = this_cpu->c_x86_vendor;
707 return;
708 }
709 }
710
711 pr_err_once("CPU: vendor_id '%s' unknown, using generic init.\n" \
712 "CPU: Your system may be unstable.\n", v);
713
714 c->x86_vendor = X86_VENDOR_UNKNOWN;
715 this_cpu = &default_cpu;
716}
717
718void cpu_detect(struct cpuinfo_x86 *c)
719{
720 /* Get vendor name */
721 cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
722 (unsigned int *)&c->x86_vendor_id[0],
723 (unsigned int *)&c->x86_vendor_id[8],
724 (unsigned int *)&c->x86_vendor_id[4]);
725
726 c->x86 = 4;
727 /* Intel-defined flags: level 0x00000001 */
728 if (c->cpuid_level >= 0x00000001) {
729 u32 junk, tfms, cap0, misc;
730
731 cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
732 c->x86 = x86_family(tfms);
733 c->x86_model = x86_model(tfms);
734 c->x86_stepping = x86_stepping(tfms);
735
736 if (cap0 & (1<<19)) {
737 c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
738 c->x86_cache_alignment = c->x86_clflush_size;
739 }
740 }
741}
742
743static void apply_forced_caps(struct cpuinfo_x86 *c)
744{
745 int i;
746
747 for (i = 0; i < NCAPINTS + NBUGINTS; i++) {
748 c->x86_capability[i] &= ~cpu_caps_cleared[i];
749 c->x86_capability[i] |= cpu_caps_set[i];
750 }
751}
752
753static void init_speculation_control(struct cpuinfo_x86 *c)
754{
755 /*
756 * The Intel SPEC_CTRL CPUID bit implies IBRS and IBPB support,
757 * and they also have a different bit for STIBP support. Also,
758 * a hypervisor might have set the individual AMD bits even on
759 * Intel CPUs, for finer-grained selection of what's available.
760 */
761 if (cpu_has(c, X86_FEATURE_SPEC_CTRL)) {
762 set_cpu_cap(c, X86_FEATURE_IBRS);
763 set_cpu_cap(c, X86_FEATURE_IBPB);
764 set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL);
765 }
766
767 if (cpu_has(c, X86_FEATURE_INTEL_STIBP))
768 set_cpu_cap(c, X86_FEATURE_STIBP);
769
770 if (cpu_has(c, X86_FEATURE_SPEC_CTRL_SSBD) ||
771 cpu_has(c, X86_FEATURE_VIRT_SSBD))
772 set_cpu_cap(c, X86_FEATURE_SSBD);
773
774 if (cpu_has(c, X86_FEATURE_AMD_IBRS)) {
775 set_cpu_cap(c, X86_FEATURE_IBRS);
776 set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL);
777 }
778
779 if (cpu_has(c, X86_FEATURE_AMD_IBPB))
780 set_cpu_cap(c, X86_FEATURE_IBPB);
781
782 if (cpu_has(c, X86_FEATURE_AMD_STIBP)) {
783 set_cpu_cap(c, X86_FEATURE_STIBP);
784 set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL);
785 }
786}
787
788void get_cpu_cap(struct cpuinfo_x86 *c)
789{
790 u32 eax, ebx, ecx, edx;
791
792 /* Intel-defined flags: level 0x00000001 */
793 if (c->cpuid_level >= 0x00000001) {
794 cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
795
796 c->x86_capability[CPUID_1_ECX] = ecx;
797 c->x86_capability[CPUID_1_EDX] = edx;
798 }
799
800 /* Thermal and Power Management Leaf: level 0x00000006 (eax) */
801 if (c->cpuid_level >= 0x00000006)
802 c->x86_capability[CPUID_6_EAX] = cpuid_eax(0x00000006);
803
804 /* Additional Intel-defined flags: level 0x00000007 */
805 if (c->cpuid_level >= 0x00000007) {
806 cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);
807 c->x86_capability[CPUID_7_0_EBX] = ebx;
808 c->x86_capability[CPUID_7_ECX] = ecx;
809 c->x86_capability[CPUID_7_EDX] = edx;
810 }
811
812 /* Extended state features: level 0x0000000d */
813 if (c->cpuid_level >= 0x0000000d) {
814 cpuid_count(0x0000000d, 1, &eax, &ebx, &ecx, &edx);
815
816 c->x86_capability[CPUID_D_1_EAX] = eax;
817 }
818
819 /* Additional Intel-defined flags: level 0x0000000F */
820 if (c->cpuid_level >= 0x0000000F) {
821
822 /* QoS sub-leaf, EAX=0Fh, ECX=0 */
823 cpuid_count(0x0000000F, 0, &eax, &ebx, &ecx, &edx);
824 c->x86_capability[CPUID_F_0_EDX] = edx;
825
826 if (cpu_has(c, X86_FEATURE_CQM_LLC)) {
827 /* will be overridden if occupancy monitoring exists */
828 c->x86_cache_max_rmid = ebx;
829
830 /* QoS sub-leaf, EAX=0Fh, ECX=1 */
831 cpuid_count(0x0000000F, 1, &eax, &ebx, &ecx, &edx);
832 c->x86_capability[CPUID_F_1_EDX] = edx;
833
834 if ((cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC)) ||
835 ((cpu_has(c, X86_FEATURE_CQM_MBM_TOTAL)) ||
836 (cpu_has(c, X86_FEATURE_CQM_MBM_LOCAL)))) {
837 c->x86_cache_max_rmid = ecx;
838 c->x86_cache_occ_scale = ebx;
839 }
840 } else {
841 c->x86_cache_max_rmid = -1;
842 c->x86_cache_occ_scale = -1;
843 }
844 }
845
846 /* AMD-defined flags: level 0x80000001 */
847 eax = cpuid_eax(0x80000000);
848 c->extended_cpuid_level = eax;
849
850 if ((eax & 0xffff0000) == 0x80000000) {
851 if (eax >= 0x80000001) {
852 cpuid(0x80000001, &eax, &ebx, &ecx, &edx);
853
854 c->x86_capability[CPUID_8000_0001_ECX] = ecx;
855 c->x86_capability[CPUID_8000_0001_EDX] = edx;
856 }
857 }
858
859 if (c->extended_cpuid_level >= 0x80000007) {
860 cpuid(0x80000007, &eax, &ebx, &ecx, &edx);
861
862 c->x86_capability[CPUID_8000_0007_EBX] = ebx;
863 c->x86_power = edx;
864 }
865
866 if (c->extended_cpuid_level >= 0x80000008) {
867 cpuid(0x80000008, &eax, &ebx, &ecx, &edx);
868 c->x86_capability[CPUID_8000_0008_EBX] = ebx;
869 }
870
871 if (c->extended_cpuid_level >= 0x8000000a)
872 c->x86_capability[CPUID_8000_000A_EDX] = cpuid_edx(0x8000000a);
873
874 init_scattered_cpuid_features(c);
875 init_speculation_control(c);
876
877 /*
878 * Clear/Set all flags overridden by options, after probe.
879 * This needs to happen each time we re-probe, which may happen
880 * several times during CPU initialization.
881 */
882 apply_forced_caps(c);
883}
884
885static void get_cpu_address_sizes(struct cpuinfo_x86 *c)
886{
887 u32 eax, ebx, ecx, edx;
888
889 if (c->extended_cpuid_level >= 0x80000008) {
890 cpuid(0x80000008, &eax, &ebx, &ecx, &edx);
891
892 c->x86_virt_bits = (eax >> 8) & 0xff;
893 c->x86_phys_bits = eax & 0xff;
894 }
895#ifdef CONFIG_X86_32
896 else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36))
897 c->x86_phys_bits = 36;
898#endif
899}
900
901static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
902{
903#ifdef CONFIG_X86_32
904 int i;
905
906 /*
907 * First of all, decide if this is a 486 or higher
908 * It's a 486 if we can modify the AC flag
909 */
910 if (flag_is_changeable_p(X86_EFLAGS_AC))
911 c->x86 = 4;
912 else
913 c->x86 = 3;
914
915 for (i = 0; i < X86_VENDOR_NUM; i++)
916 if (cpu_devs[i] && cpu_devs[i]->c_identify) {
917 c->x86_vendor_id[0] = 0;
918 cpu_devs[i]->c_identify(c);
919 if (c->x86_vendor_id[0]) {
920 get_cpu_vendor(c);
921 break;
922 }
923 }
924#endif
925}
926
927static const __initconst struct x86_cpu_id cpu_no_speculation[] = {
928 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CEDARVIEW, X86_FEATURE_ANY },
929 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_CLOVERVIEW, X86_FEATURE_ANY },
930 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_LINCROFT, X86_FEATURE_ANY },
931 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PENWELL, X86_FEATURE_ANY },
932 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_PINEVIEW, X86_FEATURE_ANY },
933 { X86_VENDOR_CENTAUR, 5 },
934 { X86_VENDOR_INTEL, 5 },
935 { X86_VENDOR_NSC, 5 },
936 { X86_VENDOR_ANY, 4 },
937 {}
938};
939
940static const __initconst struct x86_cpu_id cpu_no_meltdown[] = {
941 { X86_VENDOR_AMD },
942 {}
943};
944
945/* Only list CPUs which speculate but are non susceptible to SSB */
946static const __initconst struct x86_cpu_id cpu_no_spec_store_bypass[] = {
947 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT1 },
948 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT },
949 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_SILVERMONT2 },
950 { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_MERRIFIELD },
951 { X86_VENDOR_INTEL, 6, INTEL_FAM6_CORE_YONAH },
952 { X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNL },
953 { X86_VENDOR_INTEL, 6, INTEL_FAM6_XEON_PHI_KNM },
954 { X86_VENDOR_AMD, 0x12, },
955 { X86_VENDOR_AMD, 0x11, },
956 { X86_VENDOR_AMD, 0x10, },
957 { X86_VENDOR_AMD, 0xf, },
958 {}
959};
960
961static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
962{
963 u64 ia32_cap = 0;
964
965 if (x86_match_cpu(cpu_no_speculation))
966 return;
967
968 setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
969 setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
970
971 if (cpu_has(c, X86_FEATURE_ARCH_CAPABILITIES))
972 rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap);
973
974 if (!x86_match_cpu(cpu_no_spec_store_bypass) &&
975 !(ia32_cap & ARCH_CAP_SSB_NO))
976 setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
977
978 if (x86_match_cpu(cpu_no_meltdown))
979 return;
980
981 /* Rogue Data Cache Load? No! */
982 if (ia32_cap & ARCH_CAP_RDCL_NO)
983 return;
984
985 setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
986}
987
988/*
989 * Do minimum CPU detection early.
990 * Fields really needed: vendor, cpuid_level, family, model, mask,
991 * cache alignment.
992 * The others are not touched to avoid unwanted side effects.
993 *
994 * WARNING: this function is only called on the boot CPU. Don't add code
995 * here that is supposed to run on all CPUs.
996 */
997static void __init early_identify_cpu(struct cpuinfo_x86 *c)
998{
999#ifdef CONFIG_X86_64
1000 c->x86_clflush_size = 64;
1001 c->x86_phys_bits = 36;
1002 c->x86_virt_bits = 48;
1003#else
1004 c->x86_clflush_size = 32;
1005 c->x86_phys_bits = 32;
1006 c->x86_virt_bits = 32;
1007#endif
1008 c->x86_cache_alignment = c->x86_clflush_size;
1009
1010 memset(&c->x86_capability, 0, sizeof c->x86_capability);
1011 c->extended_cpuid_level = 0;
1012
1013 /* cyrix could have cpuid enabled via c_identify()*/
1014 if (have_cpuid_p()) {
1015 cpu_detect(c);
1016 get_cpu_vendor(c);
1017 get_cpu_cap(c);
1018 get_cpu_address_sizes(c);
1019 setup_force_cpu_cap(X86_FEATURE_CPUID);
1020
1021 if (this_cpu->c_early_init)
1022 this_cpu->c_early_init(c);
1023
1024 c->cpu_index = 0;
1025 filter_cpuid_features(c, false);
1026
1027 if (this_cpu->c_bsp_init)
1028 this_cpu->c_bsp_init(c);
1029 } else {
1030 identify_cpu_without_cpuid(c);
1031 setup_clear_cpu_cap(X86_FEATURE_CPUID);
1032 }
1033
1034 setup_force_cpu_cap(X86_FEATURE_ALWAYS);
1035
1036 cpu_set_bug_bits(c);
1037
1038 fpu__init_system(c);
1039
1040#ifdef CONFIG_X86_32
1041 /*
1042 * Regardless of whether PCID is enumerated, the SDM says
1043 * that it can't be enabled in 32-bit mode.
1044 */
1045 setup_clear_cpu_cap(X86_FEATURE_PCID);
1046#endif
1047}
1048
1049void __init early_cpu_init(void)
1050{
1051 const struct cpu_dev *const *cdev;
1052 int count = 0;
1053
1054#ifdef CONFIG_PROCESSOR_SELECT
1055 pr_info("KERNEL supported cpus:\n");
1056#endif
1057
1058 for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
1059 const struct cpu_dev *cpudev = *cdev;
1060
1061 if (count >= X86_VENDOR_NUM)
1062 break;
1063 cpu_devs[count] = cpudev;
1064 count++;
1065
1066#ifdef CONFIG_PROCESSOR_SELECT
1067 {
1068 unsigned int j;
1069
1070 for (j = 0; j < 2; j++) {
1071 if (!cpudev->c_ident[j])
1072 continue;
1073 pr_info(" %s %s\n", cpudev->c_vendor,
1074 cpudev->c_ident[j]);
1075 }
1076 }
1077#endif
1078 }
1079 early_identify_cpu(&boot_cpu_data);
1080}
1081
1082/*
1083 * The NOPL instruction is supposed to exist on all CPUs of family >= 6;
1084 * unfortunately, that's not true in practice because of early VIA
1085 * chips and (more importantly) broken virtualizers that are not easy
1086 * to detect. In the latter case it doesn't even *fail* reliably, so
1087 * probing for it doesn't even work. Disable it completely on 32-bit
1088 * unless we can find a reliable way to detect all the broken cases.
1089 * Enable it explicitly on 64-bit for non-constant inputs of cpu_has().
1090 */
1091static void detect_nopl(struct cpuinfo_x86 *c)
1092{
1093#ifdef CONFIG_X86_32
1094 clear_cpu_cap(c, X86_FEATURE_NOPL);
1095#else
1096 set_cpu_cap(c, X86_FEATURE_NOPL);
1097#endif
1098}
1099
1100static void detect_null_seg_behavior(struct cpuinfo_x86 *c)
1101{
1102#ifdef CONFIG_X86_64
1103 /*
1104 * Empirically, writing zero to a segment selector on AMD does
1105 * not clear the base, whereas writing zero to a segment
1106 * selector on Intel does clear the base. Intel's behavior
1107 * allows slightly faster context switches in the common case
1108 * where GS is unused by the prev and next threads.
1109 *
1110 * Since neither vendor documents this anywhere that I can see,
1111 * detect it directly instead of hardcoding the choice by
1112 * vendor.
1113 *
1114 * I've designated AMD's behavior as the "bug" because it's
1115 * counterintuitive and less friendly.
1116 */
1117
1118 unsigned long old_base, tmp;
1119 rdmsrl(MSR_FS_BASE, old_base);
1120 wrmsrl(MSR_FS_BASE, 1);
1121 loadsegment(fs, 0);
1122 rdmsrl(MSR_FS_BASE, tmp);
1123 if (tmp != 0)
1124 set_cpu_bug(c, X86_BUG_NULL_SEG);
1125 wrmsrl(MSR_FS_BASE, old_base);
1126#endif
1127}
1128
1129static void generic_identify(struct cpuinfo_x86 *c)
1130{
1131 c->extended_cpuid_level = 0;
1132
1133 if (!have_cpuid_p())
1134 identify_cpu_without_cpuid(c);
1135
1136 /* cyrix could have cpuid enabled via c_identify()*/
1137 if (!have_cpuid_p())
1138 return;
1139
1140 cpu_detect(c);
1141
1142 get_cpu_vendor(c);
1143
1144 get_cpu_cap(c);
1145
1146 get_cpu_address_sizes(c);
1147
1148 if (c->cpuid_level >= 0x00000001) {
1149 c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
1150#ifdef CONFIG_X86_32
1151# ifdef CONFIG_SMP
1152 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
1153# else
1154 c->apicid = c->initial_apicid;
1155# endif
1156#endif
1157 c->phys_proc_id = c->initial_apicid;
1158 }
1159
1160 get_model_name(c); /* Default name */
1161
1162 detect_nopl(c);
1163
1164 detect_null_seg_behavior(c);
1165
1166 /*
1167 * ESPFIX is a strange bug. All real CPUs have it. Paravirt
1168 * systems that run Linux at CPL > 0 may or may not have the
1169 * issue, but, even if they have the issue, there's absolutely
1170 * nothing we can do about it because we can't use the real IRET
1171 * instruction.
1172 *
1173 * NB: For the time being, only 32-bit kernels support
1174 * X86_BUG_ESPFIX as such. 64-bit kernels directly choose
1175 * whether to apply espfix using paravirt hooks. If any
1176 * non-paravirt system ever shows up that does *not* have the
1177 * ESPFIX issue, we can change this.
1178 */
1179#ifdef CONFIG_X86_32
1180# ifdef CONFIG_PARAVIRT
1181 do {
1182 extern void native_iret(void);
1183 if (pv_cpu_ops.iret == native_iret)
1184 set_cpu_bug(c, X86_BUG_ESPFIX);
1185 } while (0);
1186# else
1187 set_cpu_bug(c, X86_BUG_ESPFIX);
1188# endif
1189#endif
1190}
1191
1192static void x86_init_cache_qos(struct cpuinfo_x86 *c)
1193{
1194 /*
1195 * The heavy lifting of max_rmid and cache_occ_scale are handled
1196 * in get_cpu_cap(). Here we just set the max_rmid for the boot_cpu
1197 * in case CQM bits really aren't there in this CPU.
1198 */
1199 if (c != &boot_cpu_data) {
1200 boot_cpu_data.x86_cache_max_rmid =
1201 min(boot_cpu_data.x86_cache_max_rmid,
1202 c->x86_cache_max_rmid);
1203 }
1204}
1205
1206/*
1207 * Validate that ACPI/mptables have the same information about the
1208 * effective APIC id and update the package map.
1209 */
1210static void validate_apic_and_package_id(struct cpuinfo_x86 *c)
1211{
1212#ifdef CONFIG_SMP
1213 unsigned int apicid, cpu = smp_processor_id();
1214
1215 apicid = apic->cpu_present_to_apicid(cpu);
1216
1217 if (apicid != c->apicid) {
1218 pr_err(FW_BUG "CPU%u: APIC id mismatch. Firmware: %x APIC: %x\n",
1219 cpu, apicid, c->initial_apicid);
1220 }
1221 BUG_ON(topology_update_package_map(c->phys_proc_id, cpu));
1222#else
1223 c->logical_proc_id = 0;
1224#endif
1225}
1226
1227/*
1228 * This does the hard work of actually picking apart the CPU stuff...
1229 */
1230static void identify_cpu(struct cpuinfo_x86 *c)
1231{
1232 int i;
1233
1234 c->loops_per_jiffy = loops_per_jiffy;
1235 c->x86_cache_size = 0;
1236 c->x86_vendor = X86_VENDOR_UNKNOWN;
1237 c->x86_model = c->x86_stepping = 0; /* So far unknown... */
1238 c->x86_vendor_id[0] = '\0'; /* Unset */
1239 c->x86_model_id[0] = '\0'; /* Unset */
1240 c->x86_max_cores = 1;
1241 c->x86_coreid_bits = 0;
1242 c->cu_id = 0xff;
1243#ifdef CONFIG_X86_64
1244 c->x86_clflush_size = 64;
1245 c->x86_phys_bits = 36;
1246 c->x86_virt_bits = 48;
1247#else
1248 c->cpuid_level = -1; /* CPUID not detected */
1249 c->x86_clflush_size = 32;
1250 c->x86_phys_bits = 32;
1251 c->x86_virt_bits = 32;
1252#endif
1253 c->x86_cache_alignment = c->x86_clflush_size;
1254 memset(&c->x86_capability, 0, sizeof c->x86_capability);
1255
1256 generic_identify(c);
1257
1258 if (this_cpu->c_identify)
1259 this_cpu->c_identify(c);
1260
1261 /* Clear/Set all flags overridden by options, after probe */
1262 apply_forced_caps(c);
1263
1264#ifdef CONFIG_X86_64
1265 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
1266#endif
1267
1268 /*
1269 * Vendor-specific initialization. In this section we
1270 * canonicalize the feature flags, meaning if there are
1271 * features a certain CPU supports which CPUID doesn't
1272 * tell us, CPUID claiming incorrect flags, or other bugs,
1273 * we handle them here.
1274 *
1275 * At the end of this section, c->x86_capability better
1276 * indicate the features this CPU genuinely supports!
1277 */
1278 if (this_cpu->c_init)
1279 this_cpu->c_init(c);
1280
1281 /* Disable the PN if appropriate */
1282 squash_the_stupid_serial_number(c);
1283
1284 /* Set up SMEP/SMAP/UMIP */
1285 setup_smep(c);
1286 setup_smap(c);
1287 setup_umip(c);
1288
1289 /*
1290 * The vendor-specific functions might have changed features.
1291 * Now we do "generic changes."
1292 */
1293
1294 /* Filter out anything that depends on CPUID levels we don't have */
1295 filter_cpuid_features(c, true);
1296
1297 /* If the model name is still unset, do table lookup. */
1298 if (!c->x86_model_id[0]) {
1299 const char *p;
1300 p = table_lookup_model(c);
1301 if (p)
1302 strcpy(c->x86_model_id, p);
1303 else
1304 /* Last resort... */
1305 sprintf(c->x86_model_id, "%02x/%02x",
1306 c->x86, c->x86_model);
1307 }
1308
1309#ifdef CONFIG_X86_64
1310 detect_ht(c);
1311#endif
1312
1313 x86_init_rdrand(c);
1314 x86_init_cache_qos(c);
1315 setup_pku(c);
1316
1317 /*
1318 * Clear/Set all flags overridden by options, need do it
1319 * before following smp all cpus cap AND.
1320 */
1321 apply_forced_caps(c);
1322
1323 /*
1324 * On SMP, boot_cpu_data holds the common feature set between
1325 * all CPUs; so make sure that we indicate which features are
1326 * common between the CPUs. The first time this routine gets
1327 * executed, c == &boot_cpu_data.
1328 */
1329 if (c != &boot_cpu_data) {
1330 /* AND the already accumulated flags with these */
1331 for (i = 0; i < NCAPINTS; i++)
1332 boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
1333
1334 /* OR, i.e. replicate the bug flags */
1335 for (i = NCAPINTS; i < NCAPINTS + NBUGINTS; i++)
1336 c->x86_capability[i] |= boot_cpu_data.x86_capability[i];
1337 }
1338
1339 /* Init Machine Check Exception if available. */
1340 mcheck_cpu_init(c);
1341
1342 select_idle_routine(c);
1343
1344#ifdef CONFIG_NUMA
1345 numa_add_cpu(smp_processor_id());
1346#endif
1347}
1348
1349/*
1350 * Set up the CPU state needed to execute SYSENTER/SYSEXIT instructions
1351 * on 32-bit kernels:
1352 */
1353#ifdef CONFIG_X86_32
1354void enable_sep_cpu(void)
1355{
1356 struct tss_struct *tss;
1357 int cpu;
1358
1359 if (!boot_cpu_has(X86_FEATURE_SEP))
1360 return;
1361
1362 cpu = get_cpu();
1363 tss = &per_cpu(cpu_tss_rw, cpu);
1364
1365 /*
1366 * We cache MSR_IA32_SYSENTER_CS's value in the TSS's ss1 field --
1367 * see the big comment in struct x86_hw_tss's definition.
1368 */
1369
1370 tss->x86_tss.ss1 = __KERNEL_CS;
1371 wrmsr(MSR_IA32_SYSENTER_CS, tss->x86_tss.ss1, 0);
1372 wrmsr(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_entry_stack(cpu) + 1), 0);
1373 wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)entry_SYSENTER_32, 0);
1374
1375 put_cpu();
1376}
1377#endif
1378
1379void __init identify_boot_cpu(void)
1380{
1381 identify_cpu(&boot_cpu_data);
1382#ifdef CONFIG_X86_32
1383 sysenter_setup();
1384 enable_sep_cpu();
1385#endif
1386 cpu_detect_tlb(&boot_cpu_data);
1387}
1388
1389void identify_secondary_cpu(struct cpuinfo_x86 *c)
1390{
1391 BUG_ON(c == &boot_cpu_data);
1392 identify_cpu(c);
1393#ifdef CONFIG_X86_32
1394 enable_sep_cpu();
1395#endif
1396 mtrr_ap_init();
1397 validate_apic_and_package_id(c);
1398 x86_spec_ctrl_setup_ap();
1399}
1400
1401static __init int setup_noclflush(char *arg)
1402{
1403 setup_clear_cpu_cap(X86_FEATURE_CLFLUSH);
1404 setup_clear_cpu_cap(X86_FEATURE_CLFLUSHOPT);
1405 return 1;
1406}
1407__setup("noclflush", setup_noclflush);
1408
1409void print_cpu_info(struct cpuinfo_x86 *c)
1410{
1411 const char *vendor = NULL;
1412
1413 if (c->x86_vendor < X86_VENDOR_NUM) {
1414 vendor = this_cpu->c_vendor;
1415 } else {
1416 if (c->cpuid_level >= 0)
1417 vendor = c->x86_vendor_id;
1418 }
1419
1420 if (vendor && !strstr(c->x86_model_id, vendor))
1421 pr_cont("%s ", vendor);
1422
1423 if (c->x86_model_id[0])
1424 pr_cont("%s", c->x86_model_id);
1425 else
1426 pr_cont("%d86", c->x86);
1427
1428 pr_cont(" (family: 0x%x, model: 0x%x", c->x86, c->x86_model);
1429
1430 if (c->x86_stepping || c->cpuid_level >= 0)
1431 pr_cont(", stepping: 0x%x)\n", c->x86_stepping);
1432 else
1433 pr_cont(")\n");
1434}
1435
1436/*
1437 * clearcpuid= was already parsed in fpu__init_parse_early_param.
1438 * But we need to keep a dummy __setup around otherwise it would
1439 * show up as an environment variable for init.
1440 */
1441static __init int setup_clearcpuid(char *arg)
1442{
1443 return 1;
1444}
1445__setup("clearcpuid=", setup_clearcpuid);
1446
1447#ifdef CONFIG_X86_64
1448DEFINE_PER_CPU_FIRST(union irq_stack_union,
1449 irq_stack_union) __aligned(PAGE_SIZE) __visible;
1450EXPORT_PER_CPU_SYMBOL_GPL(irq_stack_union);
1451
1452/*
1453 * The following percpu variables are hot. Align current_task to
1454 * cacheline size such that they fall in the same cacheline.
1455 */
1456DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
1457 &init_task;
1458EXPORT_PER_CPU_SYMBOL(current_task);
1459
1460DEFINE_PER_CPU(char *, irq_stack_ptr) =
1461 init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE;
1462
1463DEFINE_PER_CPU(unsigned int, irq_count) __visible = -1;
1464
1465DEFINE_PER_CPU(int, __preempt_count) = INIT_PREEMPT_COUNT;
1466EXPORT_PER_CPU_SYMBOL(__preempt_count);
1467
1468/* May not be marked __init: used by software suspend */
1469void syscall_init(void)
1470{
1471 extern char _entry_trampoline[];
1472 extern char entry_SYSCALL_64_trampoline[];
1473
1474 int cpu = smp_processor_id();
1475 unsigned long SYSCALL64_entry_trampoline =
1476 (unsigned long)get_cpu_entry_area(cpu)->entry_trampoline +
1477 (entry_SYSCALL_64_trampoline - _entry_trampoline);
1478
1479 wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS);
1480 if (static_cpu_has(X86_FEATURE_PTI))
1481 wrmsrl(MSR_LSTAR, SYSCALL64_entry_trampoline);
1482 else
1483 wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64);
1484
1485#ifdef CONFIG_IA32_EMULATION
1486 wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL_compat);
1487 /*
1488 * This only works on Intel CPUs.
1489 * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP.
1490 * This does not cause SYSENTER to jump to the wrong location, because
1491 * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit).
1492 */
1493 wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
1494 wrmsrl_safe(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_entry_stack(cpu) + 1));
1495 wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat);
1496#else
1497 wrmsrl(MSR_CSTAR, (unsigned long)ignore_sysret);
1498 wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG);
1499 wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
1500 wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL);
1501#endif
1502
1503 /* Flags to clear on syscall */
1504 wrmsrl(MSR_SYSCALL_MASK,
1505 X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|
1506 X86_EFLAGS_IOPL|X86_EFLAGS_AC|X86_EFLAGS_NT);
1507}
1508
1509/*
1510 * Copies of the original ist values from the tss are only accessed during
1511 * debugging, no special alignment required.
1512 */
1513DEFINE_PER_CPU(struct orig_ist, orig_ist);
1514
1515static DEFINE_PER_CPU(unsigned long, debug_stack_addr);
1516DEFINE_PER_CPU(int, debug_stack_usage);
1517
1518int is_debug_stack(unsigned long addr)
1519{
1520 return __this_cpu_read(debug_stack_usage) ||
1521 (addr <= __this_cpu_read(debug_stack_addr) &&
1522 addr > (__this_cpu_read(debug_stack_addr) - DEBUG_STKSZ));
1523}
1524NOKPROBE_SYMBOL(is_debug_stack);
1525
1526DEFINE_PER_CPU(u32, debug_idt_ctr);
1527
1528void debug_stack_set_zero(void)
1529{
1530 this_cpu_inc(debug_idt_ctr);
1531 load_current_idt();
1532}
1533NOKPROBE_SYMBOL(debug_stack_set_zero);
1534
1535void debug_stack_reset(void)
1536{
1537 if (WARN_ON(!this_cpu_read(debug_idt_ctr)))
1538 return;
1539 if (this_cpu_dec_return(debug_idt_ctr) == 0)
1540 load_current_idt();
1541}
1542NOKPROBE_SYMBOL(debug_stack_reset);
1543
1544#else /* CONFIG_X86_64 */
1545
1546DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
1547EXPORT_PER_CPU_SYMBOL(current_task);
1548DEFINE_PER_CPU(int, __preempt_count) = INIT_PREEMPT_COUNT;
1549EXPORT_PER_CPU_SYMBOL(__preempt_count);
1550
1551/*
1552 * On x86_32, vm86 modifies tss.sp0, so sp0 isn't a reliable way to find
1553 * the top of the kernel stack. Use an extra percpu variable to track the
1554 * top of the kernel stack directly.
1555 */
1556DEFINE_PER_CPU(unsigned long, cpu_current_top_of_stack) =
1557 (unsigned long)&init_thread_union + THREAD_SIZE;
1558EXPORT_PER_CPU_SYMBOL(cpu_current_top_of_stack);
1559
1560#ifdef CONFIG_CC_STACKPROTECTOR
1561DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
1562#endif
1563
1564#endif /* CONFIG_X86_64 */
1565
1566/*
1567 * Clear all 6 debug registers:
1568 */
1569static void clear_all_debug_regs(void)
1570{
1571 int i;
1572
1573 for (i = 0; i < 8; i++) {
1574 /* Ignore db4, db5 */
1575 if ((i == 4) || (i == 5))
1576 continue;
1577
1578 set_debugreg(0, i);
1579 }
1580}
1581
1582#ifdef CONFIG_KGDB
1583/*
1584 * Restore debug regs if using kgdbwait and you have a kernel debugger
1585 * connection established.
1586 */
1587static void dbg_restore_debug_regs(void)
1588{
1589 if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break))
1590 arch_kgdb_ops.correct_hw_break();
1591}
1592#else /* ! CONFIG_KGDB */
1593#define dbg_restore_debug_regs()
1594#endif /* ! CONFIG_KGDB */
1595
1596static void wait_for_master_cpu(int cpu)
1597{
1598#ifdef CONFIG_SMP
1599 /*
1600 * wait for ACK from master CPU before continuing
1601 * with AP initialization
1602 */
1603 WARN_ON(cpumask_test_and_set_cpu(cpu, cpu_initialized_mask));
1604 while (!cpumask_test_cpu(cpu, cpu_callout_mask))
1605 cpu_relax();
1606#endif
1607}
1608
1609/*
1610 * cpu_init() initializes state that is per-CPU. Some data is already
1611 * initialized (naturally) in the bootstrap process, such as the GDT
1612 * and IDT. We reload them nevertheless, this function acts as a
1613 * 'CPU state barrier', nothing should get across.
1614 * A lot of state is already set up in PDA init for 64 bit
1615 */
1616#ifdef CONFIG_X86_64
1617
1618void cpu_init(void)
1619{
1620 struct orig_ist *oist;
1621 struct task_struct *me;
1622 struct tss_struct *t;
1623 unsigned long v;
1624 int cpu = raw_smp_processor_id();
1625 int i;
1626
1627 wait_for_master_cpu(cpu);
1628
1629 /*
1630 * Initialize the CR4 shadow before doing anything that could
1631 * try to read it.
1632 */
1633 cr4_init_shadow();
1634
1635 if (cpu)
1636 load_ucode_ap();
1637
1638 t = &per_cpu(cpu_tss_rw, cpu);
1639 oist = &per_cpu(orig_ist, cpu);
1640
1641#ifdef CONFIG_NUMA
1642 if (this_cpu_read(numa_node) == 0 &&
1643 early_cpu_to_node(cpu) != NUMA_NO_NODE)
1644 set_numa_node(early_cpu_to_node(cpu));
1645#endif
1646
1647 me = current;
1648
1649 pr_debug("Initializing CPU#%d\n", cpu);
1650
1651 cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1652
1653 /*
1654 * Initialize the per-CPU GDT with the boot GDT,
1655 * and set up the GDT descriptor:
1656 */
1657
1658 switch_to_new_gdt(cpu);
1659 loadsegment(fs, 0);
1660
1661 load_current_idt();
1662
1663 memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
1664 syscall_init();
1665
1666 wrmsrl(MSR_FS_BASE, 0);
1667 wrmsrl(MSR_KERNEL_GS_BASE, 0);
1668 barrier();
1669
1670 x86_configure_nx();
1671 x2apic_setup();
1672
1673 /*
1674 * set up and load the per-CPU TSS
1675 */
1676 if (!oist->ist[0]) {
1677 char *estacks = get_cpu_entry_area(cpu)->exception_stacks;
1678
1679 for (v = 0; v < N_EXCEPTION_STACKS; v++) {
1680 estacks += exception_stack_sizes[v];
1681 oist->ist[v] = t->x86_tss.ist[v] =
1682 (unsigned long)estacks;
1683 if (v == DEBUG_STACK-1)
1684 per_cpu(debug_stack_addr, cpu) = (unsigned long)estacks;
1685 }
1686 }
1687
1688 t->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
1689
1690 /*
1691 * <= is required because the CPU will access up to
1692 * 8 bits beyond the end of the IO permission bitmap.
1693 */
1694 for (i = 0; i <= IO_BITMAP_LONGS; i++)
1695 t->io_bitmap[i] = ~0UL;
1696
1697 mmgrab(&init_mm);
1698 me->active_mm = &init_mm;
1699 BUG_ON(me->mm);
1700 initialize_tlbstate_and_flush();
1701 enter_lazy_tlb(&init_mm, me);
1702
1703 /*
1704 * Initialize the TSS. sp0 points to the entry trampoline stack
1705 * regardless of what task is running.
1706 */
1707 set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
1708 load_TR_desc();
1709 load_sp0((unsigned long)(cpu_entry_stack(cpu) + 1));
1710
1711 load_mm_ldt(&init_mm);
1712
1713 clear_all_debug_regs();
1714 dbg_restore_debug_regs();
1715
1716 fpu__init_cpu();
1717
1718 if (is_uv_system())
1719 uv_cpu_init();
1720
1721 load_fixmap_gdt(cpu);
1722}
1723
1724#else
1725
1726void cpu_init(void)
1727{
1728 int cpu = smp_processor_id();
1729 struct task_struct *curr = current;
1730 struct tss_struct *t = &per_cpu(cpu_tss_rw, cpu);
1731
1732 wait_for_master_cpu(cpu);
1733
1734 /*
1735 * Initialize the CR4 shadow before doing anything that could
1736 * try to read it.
1737 */
1738 cr4_init_shadow();
1739
1740 show_ucode_info_early();
1741
1742 pr_info("Initializing CPU#%d\n", cpu);
1743
1744 if (cpu_feature_enabled(X86_FEATURE_VME) ||
1745 boot_cpu_has(X86_FEATURE_TSC) ||
1746 boot_cpu_has(X86_FEATURE_DE))
1747 cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1748
1749 load_current_idt();
1750 switch_to_new_gdt(cpu);
1751
1752 /*
1753 * Set up and load the per-CPU TSS and LDT
1754 */
1755 mmgrab(&init_mm);
1756 curr->active_mm = &init_mm;
1757 BUG_ON(curr->mm);
1758 initialize_tlbstate_and_flush();
1759 enter_lazy_tlb(&init_mm, curr);
1760
1761 /*
1762 * Initialize the TSS. Don't bother initializing sp0, as the initial
1763 * task never enters user mode.
1764 */
1765 set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
1766 load_TR_desc();
1767
1768 load_mm_ldt(&init_mm);
1769
1770 t->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
1771
1772#ifdef CONFIG_DOUBLEFAULT
1773 /* Set up doublefault TSS pointer in the GDT */
1774 __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
1775#endif
1776
1777 clear_all_debug_regs();
1778 dbg_restore_debug_regs();
1779
1780 fpu__init_cpu();
1781
1782 load_fixmap_gdt(cpu);
1783}
1784#endif
1785
1786static void bsp_resume(void)
1787{
1788 if (this_cpu->c_bsp_resume)
1789 this_cpu->c_bsp_resume(&boot_cpu_data);
1790}
1791
1792static struct syscore_ops cpu_syscore_ops = {
1793 .resume = bsp_resume,
1794};
1795
1796static int __init init_cpu_syscore(void)
1797{
1798 register_syscore_ops(&cpu_syscore_ops);
1799 return 0;
1800}
1801core_initcall(init_cpu_syscore);
1802
1803/*
1804 * The microcode loader calls this upon late microcode load to recheck features,
1805 * only when microcode has been updated. Caller holds microcode_mutex and CPU
1806 * hotplug lock.
1807 */
1808void microcode_check(void)
1809{
1810 struct cpuinfo_x86 info;
1811
1812 perf_check_microcode();
1813
1814 /* Reload CPUID max function as it might've changed. */
1815 info.cpuid_level = cpuid_eax(0);
1816
1817 /*
1818 * Copy all capability leafs to pick up the synthetic ones so that
1819 * memcmp() below doesn't fail on that. The ones coming from CPUID will
1820 * get overwritten in get_cpu_cap().
1821 */
1822 memcpy(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability));
1823
1824 get_cpu_cap(&info);
1825
1826 if (!memcmp(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability)))
1827 return;
1828
1829 pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n");
1830 pr_warn("x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
1831}
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/ctype.h>
9#include <linux/delay.h>
10#include <linux/sched.h>
11#include <linux/init.h>
12#include <linux/kprobes.h>
13#include <linux/kgdb.h>
14#include <linux/smp.h>
15#include <linux/io.h>
16#include <linux/syscore_ops.h>
17
18#include <asm/stackprotector.h>
19#include <asm/perf_event.h>
20#include <asm/mmu_context.h>
21#include <asm/archrandom.h>
22#include <asm/hypervisor.h>
23#include <asm/processor.h>
24#include <asm/tlbflush.h>
25#include <asm/debugreg.h>
26#include <asm/sections.h>
27#include <asm/vsyscall.h>
28#include <linux/topology.h>
29#include <linux/cpumask.h>
30#include <asm/pgtable.h>
31#include <linux/atomic.h>
32#include <asm/proto.h>
33#include <asm/setup.h>
34#include <asm/apic.h>
35#include <asm/desc.h>
36#include <asm/fpu/internal.h>
37#include <asm/mtrr.h>
38#include <linux/numa.h>
39#include <asm/asm.h>
40#include <asm/cpu.h>
41#include <asm/mce.h>
42#include <asm/msr.h>
43#include <asm/pat.h>
44#include <asm/microcode.h>
45#include <asm/microcode_intel.h>
46
47#ifdef CONFIG_X86_LOCAL_APIC
48#include <asm/uv/uv.h>
49#endif
50
51#include "cpu.h"
52
53/* all of these masks are initialized in setup_cpu_local_masks() */
54cpumask_var_t cpu_initialized_mask;
55cpumask_var_t cpu_callout_mask;
56cpumask_var_t cpu_callin_mask;
57
58/* representing cpus for which sibling maps can be computed */
59cpumask_var_t cpu_sibling_setup_mask;
60
61/* correctly size the local cpu masks */
62void __init setup_cpu_local_masks(void)
63{
64 alloc_bootmem_cpumask_var(&cpu_initialized_mask);
65 alloc_bootmem_cpumask_var(&cpu_callin_mask);
66 alloc_bootmem_cpumask_var(&cpu_callout_mask);
67 alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
68}
69
70static void default_init(struct cpuinfo_x86 *c)
71{
72#ifdef CONFIG_X86_64
73 cpu_detect_cache_sizes(c);
74#else
75 /* Not much we can do here... */
76 /* Check if at least it has cpuid */
77 if (c->cpuid_level == -1) {
78 /* No cpuid. It must be an ancient CPU */
79 if (c->x86 == 4)
80 strcpy(c->x86_model_id, "486");
81 else if (c->x86 == 3)
82 strcpy(c->x86_model_id, "386");
83 }
84#endif
85}
86
87static const struct cpu_dev default_cpu = {
88 .c_init = default_init,
89 .c_vendor = "Unknown",
90 .c_x86_vendor = X86_VENDOR_UNKNOWN,
91};
92
93static const struct cpu_dev *this_cpu = &default_cpu;
94
95DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
96#ifdef CONFIG_X86_64
97 /*
98 * We need valid kernel segments for data and code in long mode too
99 * IRET will check the segment types kkeil 2000/10/28
100 * Also sysret mandates a special GDT layout
101 *
102 * TLS descriptors are currently at a different place compared to i386.
103 * Hopefully nobody expects them at a fixed place (Wine?)
104 */
105 [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
106 [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
107 [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
108 [GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff),
109 [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff),
110 [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff),
111#else
112 [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff),
113 [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
114 [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff),
115 [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff),
116 /*
117 * Segments used for calling PnP BIOS have byte granularity.
118 * They code segments and data segments have fixed 64k limits,
119 * the transfer segment sizes are set at run time.
120 */
121 /* 32-bit code */
122 [GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
123 /* 16-bit code */
124 [GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
125 /* 16-bit data */
126 [GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(0x0092, 0, 0xffff),
127 /* 16-bit data */
128 [GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(0x0092, 0, 0),
129 /* 16-bit data */
130 [GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(0x0092, 0, 0),
131 /*
132 * The APM segments have byte granularity and their bases
133 * are set at run time. All have 64k limits.
134 */
135 /* 32-bit code */
136 [GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
137 /* 16-bit code */
138 [GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
139 /* data */
140 [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff),
141
142 [GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
143 [GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
144 GDT_STACK_CANARY_INIT
145#endif
146} };
147EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
148
149static int __init x86_mpx_setup(char *s)
150{
151 /* require an exact match without trailing characters */
152 if (strlen(s))
153 return 0;
154
155 /* do not emit a message if the feature is not present */
156 if (!boot_cpu_has(X86_FEATURE_MPX))
157 return 1;
158
159 setup_clear_cpu_cap(X86_FEATURE_MPX);
160 pr_info("nompx: Intel Memory Protection Extensions (MPX) disabled\n");
161 return 1;
162}
163__setup("nompx", x86_mpx_setup);
164
165static int __init x86_noinvpcid_setup(char *s)
166{
167 /* noinvpcid doesn't accept parameters */
168 if (s)
169 return -EINVAL;
170
171 /* do not emit a message if the feature is not present */
172 if (!boot_cpu_has(X86_FEATURE_INVPCID))
173 return 0;
174
175 setup_clear_cpu_cap(X86_FEATURE_INVPCID);
176 pr_info("noinvpcid: INVPCID feature disabled\n");
177 return 0;
178}
179early_param("noinvpcid", x86_noinvpcid_setup);
180
181#ifdef CONFIG_X86_32
182static int cachesize_override = -1;
183static int disable_x86_serial_nr = 1;
184
185static int __init cachesize_setup(char *str)
186{
187 get_option(&str, &cachesize_override);
188 return 1;
189}
190__setup("cachesize=", cachesize_setup);
191
192static int __init x86_sep_setup(char *s)
193{
194 setup_clear_cpu_cap(X86_FEATURE_SEP);
195 return 1;
196}
197__setup("nosep", x86_sep_setup);
198
199/* Standard macro to see if a specific flag is changeable */
200static inline int flag_is_changeable_p(u32 flag)
201{
202 u32 f1, f2;
203
204 /*
205 * Cyrix and IDT cpus allow disabling of CPUID
206 * so the code below may return different results
207 * when it is executed before and after enabling
208 * the CPUID. Add "volatile" to not allow gcc to
209 * optimize the subsequent calls to this function.
210 */
211 asm volatile ("pushfl \n\t"
212 "pushfl \n\t"
213 "popl %0 \n\t"
214 "movl %0, %1 \n\t"
215 "xorl %2, %0 \n\t"
216 "pushl %0 \n\t"
217 "popfl \n\t"
218 "pushfl \n\t"
219 "popl %0 \n\t"
220 "popfl \n\t"
221
222 : "=&r" (f1), "=&r" (f2)
223 : "ir" (flag));
224
225 return ((f1^f2) & flag) != 0;
226}
227
228/* Probe for the CPUID instruction */
229int have_cpuid_p(void)
230{
231 return flag_is_changeable_p(X86_EFLAGS_ID);
232}
233
234static void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
235{
236 unsigned long lo, hi;
237
238 if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr)
239 return;
240
241 /* Disable processor serial number: */
242
243 rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
244 lo |= 0x200000;
245 wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
246
247 pr_notice("CPU serial number disabled.\n");
248 clear_cpu_cap(c, X86_FEATURE_PN);
249
250 /* Disabling the serial number may affect the cpuid level */
251 c->cpuid_level = cpuid_eax(0);
252}
253
254static int __init x86_serial_nr_setup(char *s)
255{
256 disable_x86_serial_nr = 0;
257 return 1;
258}
259__setup("serialnumber", x86_serial_nr_setup);
260#else
261static inline int flag_is_changeable_p(u32 flag)
262{
263 return 1;
264}
265static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
266{
267}
268#endif
269
270static __init int setup_disable_smep(char *arg)
271{
272 setup_clear_cpu_cap(X86_FEATURE_SMEP);
273 return 1;
274}
275__setup("nosmep", setup_disable_smep);
276
277static __always_inline void setup_smep(struct cpuinfo_x86 *c)
278{
279 if (cpu_has(c, X86_FEATURE_SMEP))
280 cr4_set_bits(X86_CR4_SMEP);
281}
282
283static __init int setup_disable_smap(char *arg)
284{
285 setup_clear_cpu_cap(X86_FEATURE_SMAP);
286 return 1;
287}
288__setup("nosmap", setup_disable_smap);
289
290static __always_inline void setup_smap(struct cpuinfo_x86 *c)
291{
292 unsigned long eflags = native_save_fl();
293
294 /* This should have been cleared long ago */
295 BUG_ON(eflags & X86_EFLAGS_AC);
296
297 if (cpu_has(c, X86_FEATURE_SMAP)) {
298#ifdef CONFIG_X86_SMAP
299 cr4_set_bits(X86_CR4_SMAP);
300#else
301 cr4_clear_bits(X86_CR4_SMAP);
302#endif
303 }
304}
305
306/*
307 * Protection Keys are not available in 32-bit mode.
308 */
309static bool pku_disabled;
310
311static __always_inline void setup_pku(struct cpuinfo_x86 *c)
312{
313 if (!cpu_has(c, X86_FEATURE_PKU))
314 return;
315 if (pku_disabled)
316 return;
317
318 cr4_set_bits(X86_CR4_PKE);
319 /*
320 * Seting X86_CR4_PKE will cause the X86_FEATURE_OSPKE
321 * cpuid bit to be set. We need to ensure that we
322 * update that bit in this CPU's "cpu_info".
323 */
324 get_cpu_cap(c);
325}
326
327#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
328static __init int setup_disable_pku(char *arg)
329{
330 /*
331 * Do not clear the X86_FEATURE_PKU bit. All of the
332 * runtime checks are against OSPKE so clearing the
333 * bit does nothing.
334 *
335 * This way, we will see "pku" in cpuinfo, but not
336 * "ospke", which is exactly what we want. It shows
337 * that the CPU has PKU, but the OS has not enabled it.
338 * This happens to be exactly how a system would look
339 * if we disabled the config option.
340 */
341 pr_info("x86: 'nopku' specified, disabling Memory Protection Keys\n");
342 pku_disabled = true;
343 return 1;
344}
345__setup("nopku", setup_disable_pku);
346#endif /* CONFIG_X86_64 */
347
348/*
349 * Some CPU features depend on higher CPUID levels, which may not always
350 * be available due to CPUID level capping or broken virtualization
351 * software. Add those features to this table to auto-disable them.
352 */
353struct cpuid_dependent_feature {
354 u32 feature;
355 u32 level;
356};
357
358static const struct cpuid_dependent_feature
359cpuid_dependent_features[] = {
360 { X86_FEATURE_MWAIT, 0x00000005 },
361 { X86_FEATURE_DCA, 0x00000009 },
362 { X86_FEATURE_XSAVE, 0x0000000d },
363 { 0, 0 }
364};
365
366static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
367{
368 const struct cpuid_dependent_feature *df;
369
370 for (df = cpuid_dependent_features; df->feature; df++) {
371
372 if (!cpu_has(c, df->feature))
373 continue;
374 /*
375 * Note: cpuid_level is set to -1 if unavailable, but
376 * extended_extended_level is set to 0 if unavailable
377 * and the legitimate extended levels are all negative
378 * when signed; hence the weird messing around with
379 * signs here...
380 */
381 if (!((s32)df->level < 0 ?
382 (u32)df->level > (u32)c->extended_cpuid_level :
383 (s32)df->level > (s32)c->cpuid_level))
384 continue;
385
386 clear_cpu_cap(c, df->feature);
387 if (!warn)
388 continue;
389
390 pr_warn("CPU: CPU feature " X86_CAP_FMT " disabled, no CPUID level 0x%x\n",
391 x86_cap_flag(df->feature), df->level);
392 }
393}
394
395/*
396 * Naming convention should be: <Name> [(<Codename>)]
397 * This table only is used unless init_<vendor>() below doesn't set it;
398 * in particular, if CPUID levels 0x80000002..4 are supported, this
399 * isn't used
400 */
401
402/* Look up CPU names by table lookup. */
403static const char *table_lookup_model(struct cpuinfo_x86 *c)
404{
405#ifdef CONFIG_X86_32
406 const struct legacy_cpu_model_info *info;
407
408 if (c->x86_model >= 16)
409 return NULL; /* Range check */
410
411 if (!this_cpu)
412 return NULL;
413
414 info = this_cpu->legacy_models;
415
416 while (info->family) {
417 if (info->family == c->x86)
418 return info->model_names[c->x86_model];
419 info++;
420 }
421#endif
422 return NULL; /* Not found */
423}
424
425__u32 cpu_caps_cleared[NCAPINTS];
426__u32 cpu_caps_set[NCAPINTS];
427
428void load_percpu_segment(int cpu)
429{
430#ifdef CONFIG_X86_32
431 loadsegment(fs, __KERNEL_PERCPU);
432#else
433 loadsegment(gs, 0);
434 wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
435#endif
436 load_stack_canary_segment();
437}
438
439/*
440 * Current gdt points %fs at the "master" per-cpu area: after this,
441 * it's on the real one.
442 */
443void switch_to_new_gdt(int cpu)
444{
445 struct desc_ptr gdt_descr;
446
447 gdt_descr.address = (long)get_cpu_gdt_table(cpu);
448 gdt_descr.size = GDT_SIZE - 1;
449 load_gdt(&gdt_descr);
450 /* Reload the per-cpu base */
451
452 load_percpu_segment(cpu);
453}
454
455static const struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
456
457static void get_model_name(struct cpuinfo_x86 *c)
458{
459 unsigned int *v;
460 char *p, *q, *s;
461
462 if (c->extended_cpuid_level < 0x80000004)
463 return;
464
465 v = (unsigned int *)c->x86_model_id;
466 cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
467 cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
468 cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
469 c->x86_model_id[48] = 0;
470
471 /* Trim whitespace */
472 p = q = s = &c->x86_model_id[0];
473
474 while (*p == ' ')
475 p++;
476
477 while (*p) {
478 /* Note the last non-whitespace index */
479 if (!isspace(*p))
480 s = q;
481
482 *q++ = *p++;
483 }
484
485 *(s + 1) = '\0';
486}
487
488void cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
489{
490 unsigned int n, dummy, ebx, ecx, edx, l2size;
491
492 n = c->extended_cpuid_level;
493
494 if (n >= 0x80000005) {
495 cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
496 c->x86_cache_size = (ecx>>24) + (edx>>24);
497#ifdef CONFIG_X86_64
498 /* On K8 L1 TLB is inclusive, so don't count it */
499 c->x86_tlbsize = 0;
500#endif
501 }
502
503 if (n < 0x80000006) /* Some chips just has a large L1. */
504 return;
505
506 cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
507 l2size = ecx >> 16;
508
509#ifdef CONFIG_X86_64
510 c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
511#else
512 /* do processor-specific cache resizing */
513 if (this_cpu->legacy_cache_size)
514 l2size = this_cpu->legacy_cache_size(c, l2size);
515
516 /* Allow user to override all this if necessary. */
517 if (cachesize_override != -1)
518 l2size = cachesize_override;
519
520 if (l2size == 0)
521 return; /* Again, no L2 cache is possible */
522#endif
523
524 c->x86_cache_size = l2size;
525}
526
527u16 __read_mostly tlb_lli_4k[NR_INFO];
528u16 __read_mostly tlb_lli_2m[NR_INFO];
529u16 __read_mostly tlb_lli_4m[NR_INFO];
530u16 __read_mostly tlb_lld_4k[NR_INFO];
531u16 __read_mostly tlb_lld_2m[NR_INFO];
532u16 __read_mostly tlb_lld_4m[NR_INFO];
533u16 __read_mostly tlb_lld_1g[NR_INFO];
534
535static void cpu_detect_tlb(struct cpuinfo_x86 *c)
536{
537 if (this_cpu->c_detect_tlb)
538 this_cpu->c_detect_tlb(c);
539
540 pr_info("Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n",
541 tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES],
542 tlb_lli_4m[ENTRIES]);
543
544 pr_info("Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d, 1GB %d\n",
545 tlb_lld_4k[ENTRIES], tlb_lld_2m[ENTRIES],
546 tlb_lld_4m[ENTRIES], tlb_lld_1g[ENTRIES]);
547}
548
549void detect_ht(struct cpuinfo_x86 *c)
550{
551#ifdef CONFIG_SMP
552 u32 eax, ebx, ecx, edx;
553 int index_msb, core_bits;
554 static bool printed;
555
556 if (!cpu_has(c, X86_FEATURE_HT))
557 return;
558
559 if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
560 goto out;
561
562 if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
563 return;
564
565 cpuid(1, &eax, &ebx, &ecx, &edx);
566
567 smp_num_siblings = (ebx & 0xff0000) >> 16;
568
569 if (smp_num_siblings == 1) {
570 pr_info_once("CPU0: Hyper-Threading is disabled\n");
571 goto out;
572 }
573
574 if (smp_num_siblings <= 1)
575 goto out;
576
577 index_msb = get_count_order(smp_num_siblings);
578 c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
579
580 smp_num_siblings = smp_num_siblings / c->x86_max_cores;
581
582 index_msb = get_count_order(smp_num_siblings);
583
584 core_bits = get_count_order(c->x86_max_cores);
585
586 c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
587 ((1 << core_bits) - 1);
588
589out:
590 if (!printed && (c->x86_max_cores * smp_num_siblings) > 1) {
591 pr_info("CPU: Physical Processor ID: %d\n",
592 c->phys_proc_id);
593 pr_info("CPU: Processor Core ID: %d\n",
594 c->cpu_core_id);
595 printed = 1;
596 }
597#endif
598}
599
600static void get_cpu_vendor(struct cpuinfo_x86 *c)
601{
602 char *v = c->x86_vendor_id;
603 int i;
604
605 for (i = 0; i < X86_VENDOR_NUM; i++) {
606 if (!cpu_devs[i])
607 break;
608
609 if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
610 (cpu_devs[i]->c_ident[1] &&
611 !strcmp(v, cpu_devs[i]->c_ident[1]))) {
612
613 this_cpu = cpu_devs[i];
614 c->x86_vendor = this_cpu->c_x86_vendor;
615 return;
616 }
617 }
618
619 pr_err_once("CPU: vendor_id '%s' unknown, using generic init.\n" \
620 "CPU: Your system may be unstable.\n", v);
621
622 c->x86_vendor = X86_VENDOR_UNKNOWN;
623 this_cpu = &default_cpu;
624}
625
626void cpu_detect(struct cpuinfo_x86 *c)
627{
628 /* Get vendor name */
629 cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
630 (unsigned int *)&c->x86_vendor_id[0],
631 (unsigned int *)&c->x86_vendor_id[8],
632 (unsigned int *)&c->x86_vendor_id[4]);
633
634 c->x86 = 4;
635 /* Intel-defined flags: level 0x00000001 */
636 if (c->cpuid_level >= 0x00000001) {
637 u32 junk, tfms, cap0, misc;
638
639 cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
640 c->x86 = x86_family(tfms);
641 c->x86_model = x86_model(tfms);
642 c->x86_mask = x86_stepping(tfms);
643
644 if (cap0 & (1<<19)) {
645 c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
646 c->x86_cache_alignment = c->x86_clflush_size;
647 }
648 }
649}
650
651void get_cpu_cap(struct cpuinfo_x86 *c)
652{
653 u32 eax, ebx, ecx, edx;
654
655 /* Intel-defined flags: level 0x00000001 */
656 if (c->cpuid_level >= 0x00000001) {
657 cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
658
659 c->x86_capability[CPUID_1_ECX] = ecx;
660 c->x86_capability[CPUID_1_EDX] = edx;
661 }
662
663 /* Additional Intel-defined flags: level 0x00000007 */
664 if (c->cpuid_level >= 0x00000007) {
665 cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);
666
667 c->x86_capability[CPUID_7_0_EBX] = ebx;
668
669 c->x86_capability[CPUID_6_EAX] = cpuid_eax(0x00000006);
670 c->x86_capability[CPUID_7_ECX] = ecx;
671 }
672
673 /* Extended state features: level 0x0000000d */
674 if (c->cpuid_level >= 0x0000000d) {
675 cpuid_count(0x0000000d, 1, &eax, &ebx, &ecx, &edx);
676
677 c->x86_capability[CPUID_D_1_EAX] = eax;
678 }
679
680 /* Additional Intel-defined flags: level 0x0000000F */
681 if (c->cpuid_level >= 0x0000000F) {
682
683 /* QoS sub-leaf, EAX=0Fh, ECX=0 */
684 cpuid_count(0x0000000F, 0, &eax, &ebx, &ecx, &edx);
685 c->x86_capability[CPUID_F_0_EDX] = edx;
686
687 if (cpu_has(c, X86_FEATURE_CQM_LLC)) {
688 /* will be overridden if occupancy monitoring exists */
689 c->x86_cache_max_rmid = ebx;
690
691 /* QoS sub-leaf, EAX=0Fh, ECX=1 */
692 cpuid_count(0x0000000F, 1, &eax, &ebx, &ecx, &edx);
693 c->x86_capability[CPUID_F_1_EDX] = edx;
694
695 if ((cpu_has(c, X86_FEATURE_CQM_OCCUP_LLC)) ||
696 ((cpu_has(c, X86_FEATURE_CQM_MBM_TOTAL)) ||
697 (cpu_has(c, X86_FEATURE_CQM_MBM_LOCAL)))) {
698 c->x86_cache_max_rmid = ecx;
699 c->x86_cache_occ_scale = ebx;
700 }
701 } else {
702 c->x86_cache_max_rmid = -1;
703 c->x86_cache_occ_scale = -1;
704 }
705 }
706
707 /* AMD-defined flags: level 0x80000001 */
708 eax = cpuid_eax(0x80000000);
709 c->extended_cpuid_level = eax;
710
711 if ((eax & 0xffff0000) == 0x80000000) {
712 if (eax >= 0x80000001) {
713 cpuid(0x80000001, &eax, &ebx, &ecx, &edx);
714
715 c->x86_capability[CPUID_8000_0001_ECX] = ecx;
716 c->x86_capability[CPUID_8000_0001_EDX] = edx;
717 }
718 }
719
720 if (c->extended_cpuid_level >= 0x80000008) {
721 cpuid(0x80000008, &eax, &ebx, &ecx, &edx);
722
723 c->x86_virt_bits = (eax >> 8) & 0xff;
724 c->x86_phys_bits = eax & 0xff;
725 c->x86_capability[CPUID_8000_0008_EBX] = ebx;
726 }
727#ifdef CONFIG_X86_32
728 else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36))
729 c->x86_phys_bits = 36;
730#endif
731
732 if (c->extended_cpuid_level >= 0x80000007)
733 c->x86_power = cpuid_edx(0x80000007);
734
735 if (c->extended_cpuid_level >= 0x8000000a)
736 c->x86_capability[CPUID_8000_000A_EDX] = cpuid_edx(0x8000000a);
737
738 init_scattered_cpuid_features(c);
739}
740
741static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
742{
743#ifdef CONFIG_X86_32
744 int i;
745
746 /*
747 * First of all, decide if this is a 486 or higher
748 * It's a 486 if we can modify the AC flag
749 */
750 if (flag_is_changeable_p(X86_EFLAGS_AC))
751 c->x86 = 4;
752 else
753 c->x86 = 3;
754
755 for (i = 0; i < X86_VENDOR_NUM; i++)
756 if (cpu_devs[i] && cpu_devs[i]->c_identify) {
757 c->x86_vendor_id[0] = 0;
758 cpu_devs[i]->c_identify(c);
759 if (c->x86_vendor_id[0]) {
760 get_cpu_vendor(c);
761 break;
762 }
763 }
764#endif
765}
766
767/*
768 * Do minimum CPU detection early.
769 * Fields really needed: vendor, cpuid_level, family, model, mask,
770 * cache alignment.
771 * The others are not touched to avoid unwanted side effects.
772 *
773 * WARNING: this function is only called on the BP. Don't add code here
774 * that is supposed to run on all CPUs.
775 */
776static void __init early_identify_cpu(struct cpuinfo_x86 *c)
777{
778#ifdef CONFIG_X86_64
779 c->x86_clflush_size = 64;
780 c->x86_phys_bits = 36;
781 c->x86_virt_bits = 48;
782#else
783 c->x86_clflush_size = 32;
784 c->x86_phys_bits = 32;
785 c->x86_virt_bits = 32;
786#endif
787 c->x86_cache_alignment = c->x86_clflush_size;
788
789 memset(&c->x86_capability, 0, sizeof c->x86_capability);
790 c->extended_cpuid_level = 0;
791
792 if (!have_cpuid_p())
793 identify_cpu_without_cpuid(c);
794
795 /* cyrix could have cpuid enabled via c_identify()*/
796 if (!have_cpuid_p())
797 return;
798
799 cpu_detect(c);
800 get_cpu_vendor(c);
801 get_cpu_cap(c);
802
803 if (this_cpu->c_early_init)
804 this_cpu->c_early_init(c);
805
806 c->cpu_index = 0;
807 filter_cpuid_features(c, false);
808
809 if (this_cpu->c_bsp_init)
810 this_cpu->c_bsp_init(c);
811
812 setup_force_cpu_cap(X86_FEATURE_ALWAYS);
813 fpu__init_system(c);
814}
815
816void __init early_cpu_init(void)
817{
818 const struct cpu_dev *const *cdev;
819 int count = 0;
820
821#ifdef CONFIG_PROCESSOR_SELECT
822 pr_info("KERNEL supported cpus:\n");
823#endif
824
825 for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
826 const struct cpu_dev *cpudev = *cdev;
827
828 if (count >= X86_VENDOR_NUM)
829 break;
830 cpu_devs[count] = cpudev;
831 count++;
832
833#ifdef CONFIG_PROCESSOR_SELECT
834 {
835 unsigned int j;
836
837 for (j = 0; j < 2; j++) {
838 if (!cpudev->c_ident[j])
839 continue;
840 pr_info(" %s %s\n", cpudev->c_vendor,
841 cpudev->c_ident[j]);
842 }
843 }
844#endif
845 }
846 early_identify_cpu(&boot_cpu_data);
847}
848
849/*
850 * The NOPL instruction is supposed to exist on all CPUs of family >= 6;
851 * unfortunately, that's not true in practice because of early VIA
852 * chips and (more importantly) broken virtualizers that are not easy
853 * to detect. In the latter case it doesn't even *fail* reliably, so
854 * probing for it doesn't even work. Disable it completely on 32-bit
855 * unless we can find a reliable way to detect all the broken cases.
856 * Enable it explicitly on 64-bit for non-constant inputs of cpu_has().
857 */
858static void detect_nopl(struct cpuinfo_x86 *c)
859{
860#ifdef CONFIG_X86_32
861 clear_cpu_cap(c, X86_FEATURE_NOPL);
862#else
863 set_cpu_cap(c, X86_FEATURE_NOPL);
864#endif
865
866 /*
867 * ESPFIX is a strange bug. All real CPUs have it. Paravirt
868 * systems that run Linux at CPL > 0 may or may not have the
869 * issue, but, even if they have the issue, there's absolutely
870 * nothing we can do about it because we can't use the real IRET
871 * instruction.
872 *
873 * NB: For the time being, only 32-bit kernels support
874 * X86_BUG_ESPFIX as such. 64-bit kernels directly choose
875 * whether to apply espfix using paravirt hooks. If any
876 * non-paravirt system ever shows up that does *not* have the
877 * ESPFIX issue, we can change this.
878 */
879#ifdef CONFIG_X86_32
880#ifdef CONFIG_PARAVIRT
881 do {
882 extern void native_iret(void);
883 if (pv_cpu_ops.iret == native_iret)
884 set_cpu_bug(c, X86_BUG_ESPFIX);
885 } while (0);
886#else
887 set_cpu_bug(c, X86_BUG_ESPFIX);
888#endif
889#endif
890}
891
892static void generic_identify(struct cpuinfo_x86 *c)
893{
894 c->extended_cpuid_level = 0;
895
896 if (!have_cpuid_p())
897 identify_cpu_without_cpuid(c);
898
899 /* cyrix could have cpuid enabled via c_identify()*/
900 if (!have_cpuid_p())
901 return;
902
903 cpu_detect(c);
904
905 get_cpu_vendor(c);
906
907 get_cpu_cap(c);
908
909 if (c->cpuid_level >= 0x00000001) {
910 c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
911#ifdef CONFIG_X86_32
912# ifdef CONFIG_SMP
913 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
914# else
915 c->apicid = c->initial_apicid;
916# endif
917#endif
918 c->phys_proc_id = c->initial_apicid;
919 }
920
921 get_model_name(c); /* Default name */
922
923 detect_nopl(c);
924}
925
926static void x86_init_cache_qos(struct cpuinfo_x86 *c)
927{
928 /*
929 * The heavy lifting of max_rmid and cache_occ_scale are handled
930 * in get_cpu_cap(). Here we just set the max_rmid for the boot_cpu
931 * in case CQM bits really aren't there in this CPU.
932 */
933 if (c != &boot_cpu_data) {
934 boot_cpu_data.x86_cache_max_rmid =
935 min(boot_cpu_data.x86_cache_max_rmid,
936 c->x86_cache_max_rmid);
937 }
938}
939
940/*
941 * This does the hard work of actually picking apart the CPU stuff...
942 */
943static void identify_cpu(struct cpuinfo_x86 *c)
944{
945 int i;
946
947 c->loops_per_jiffy = loops_per_jiffy;
948 c->x86_cache_size = -1;
949 c->x86_vendor = X86_VENDOR_UNKNOWN;
950 c->x86_model = c->x86_mask = 0; /* So far unknown... */
951 c->x86_vendor_id[0] = '\0'; /* Unset */
952 c->x86_model_id[0] = '\0'; /* Unset */
953 c->x86_max_cores = 1;
954 c->x86_coreid_bits = 0;
955#ifdef CONFIG_X86_64
956 c->x86_clflush_size = 64;
957 c->x86_phys_bits = 36;
958 c->x86_virt_bits = 48;
959#else
960 c->cpuid_level = -1; /* CPUID not detected */
961 c->x86_clflush_size = 32;
962 c->x86_phys_bits = 32;
963 c->x86_virt_bits = 32;
964#endif
965 c->x86_cache_alignment = c->x86_clflush_size;
966 memset(&c->x86_capability, 0, sizeof c->x86_capability);
967
968 generic_identify(c);
969
970 if (this_cpu->c_identify)
971 this_cpu->c_identify(c);
972
973 /* Clear/Set all flags overridden by options, after probe */
974 for (i = 0; i < NCAPINTS; i++) {
975 c->x86_capability[i] &= ~cpu_caps_cleared[i];
976 c->x86_capability[i] |= cpu_caps_set[i];
977 }
978
979#ifdef CONFIG_X86_64
980 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
981#endif
982
983 /*
984 * Vendor-specific initialization. In this section we
985 * canonicalize the feature flags, meaning if there are
986 * features a certain CPU supports which CPUID doesn't
987 * tell us, CPUID claiming incorrect flags, or other bugs,
988 * we handle them here.
989 *
990 * At the end of this section, c->x86_capability better
991 * indicate the features this CPU genuinely supports!
992 */
993 if (this_cpu->c_init)
994 this_cpu->c_init(c);
995
996 /* Disable the PN if appropriate */
997 squash_the_stupid_serial_number(c);
998
999 /* Set up SMEP/SMAP */
1000 setup_smep(c);
1001 setup_smap(c);
1002
1003 /*
1004 * The vendor-specific functions might have changed features.
1005 * Now we do "generic changes."
1006 */
1007
1008 /* Filter out anything that depends on CPUID levels we don't have */
1009 filter_cpuid_features(c, true);
1010
1011 /* If the model name is still unset, do table lookup. */
1012 if (!c->x86_model_id[0]) {
1013 const char *p;
1014 p = table_lookup_model(c);
1015 if (p)
1016 strcpy(c->x86_model_id, p);
1017 else
1018 /* Last resort... */
1019 sprintf(c->x86_model_id, "%02x/%02x",
1020 c->x86, c->x86_model);
1021 }
1022
1023#ifdef CONFIG_X86_64
1024 detect_ht(c);
1025#endif
1026
1027 init_hypervisor(c);
1028 x86_init_rdrand(c);
1029 x86_init_cache_qos(c);
1030 setup_pku(c);
1031
1032 /*
1033 * Clear/Set all flags overridden by options, need do it
1034 * before following smp all cpus cap AND.
1035 */
1036 for (i = 0; i < NCAPINTS; i++) {
1037 c->x86_capability[i] &= ~cpu_caps_cleared[i];
1038 c->x86_capability[i] |= cpu_caps_set[i];
1039 }
1040
1041 /*
1042 * On SMP, boot_cpu_data holds the common feature set between
1043 * all CPUs; so make sure that we indicate which features are
1044 * common between the CPUs. The first time this routine gets
1045 * executed, c == &boot_cpu_data.
1046 */
1047 if (c != &boot_cpu_data) {
1048 /* AND the already accumulated flags with these */
1049 for (i = 0; i < NCAPINTS; i++)
1050 boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
1051
1052 /* OR, i.e. replicate the bug flags */
1053 for (i = NCAPINTS; i < NCAPINTS + NBUGINTS; i++)
1054 c->x86_capability[i] |= boot_cpu_data.x86_capability[i];
1055 }
1056
1057 /* Init Machine Check Exception if available. */
1058 mcheck_cpu_init(c);
1059
1060 select_idle_routine(c);
1061
1062#ifdef CONFIG_NUMA
1063 numa_add_cpu(smp_processor_id());
1064#endif
1065 /* The boot/hotplug time assigment got cleared, restore it */
1066 c->logical_proc_id = topology_phys_to_logical_pkg(c->phys_proc_id);
1067}
1068
1069/*
1070 * Set up the CPU state needed to execute SYSENTER/SYSEXIT instructions
1071 * on 32-bit kernels:
1072 */
1073#ifdef CONFIG_X86_32
1074void enable_sep_cpu(void)
1075{
1076 struct tss_struct *tss;
1077 int cpu;
1078
1079 cpu = get_cpu();
1080 tss = &per_cpu(cpu_tss, cpu);
1081
1082 if (!boot_cpu_has(X86_FEATURE_SEP))
1083 goto out;
1084
1085 /*
1086 * We cache MSR_IA32_SYSENTER_CS's value in the TSS's ss1 field --
1087 * see the big comment in struct x86_hw_tss's definition.
1088 */
1089
1090 tss->x86_tss.ss1 = __KERNEL_CS;
1091 wrmsr(MSR_IA32_SYSENTER_CS, tss->x86_tss.ss1, 0);
1092
1093 wrmsr(MSR_IA32_SYSENTER_ESP,
1094 (unsigned long)tss + offsetofend(struct tss_struct, SYSENTER_stack),
1095 0);
1096
1097 wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)entry_SYSENTER_32, 0);
1098
1099out:
1100 put_cpu();
1101}
1102#endif
1103
1104void __init identify_boot_cpu(void)
1105{
1106 identify_cpu(&boot_cpu_data);
1107 init_amd_e400_c1e_mask();
1108#ifdef CONFIG_X86_32
1109 sysenter_setup();
1110 enable_sep_cpu();
1111#endif
1112 cpu_detect_tlb(&boot_cpu_data);
1113}
1114
1115void identify_secondary_cpu(struct cpuinfo_x86 *c)
1116{
1117 BUG_ON(c == &boot_cpu_data);
1118 identify_cpu(c);
1119#ifdef CONFIG_X86_32
1120 enable_sep_cpu();
1121#endif
1122 mtrr_ap_init();
1123}
1124
1125struct msr_range {
1126 unsigned min;
1127 unsigned max;
1128};
1129
1130static const struct msr_range msr_range_array[] = {
1131 { 0x00000000, 0x00000418},
1132 { 0xc0000000, 0xc000040b},
1133 { 0xc0010000, 0xc0010142},
1134 { 0xc0011000, 0xc001103b},
1135};
1136
1137static void __print_cpu_msr(void)
1138{
1139 unsigned index_min, index_max;
1140 unsigned index;
1141 u64 val;
1142 int i;
1143
1144 for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
1145 index_min = msr_range_array[i].min;
1146 index_max = msr_range_array[i].max;
1147
1148 for (index = index_min; index < index_max; index++) {
1149 if (rdmsrl_safe(index, &val))
1150 continue;
1151 pr_info(" MSR%08x: %016llx\n", index, val);
1152 }
1153 }
1154}
1155
1156static int show_msr;
1157
1158static __init int setup_show_msr(char *arg)
1159{
1160 int num;
1161
1162 get_option(&arg, &num);
1163
1164 if (num > 0)
1165 show_msr = num;
1166 return 1;
1167}
1168__setup("show_msr=", setup_show_msr);
1169
1170static __init int setup_noclflush(char *arg)
1171{
1172 setup_clear_cpu_cap(X86_FEATURE_CLFLUSH);
1173 setup_clear_cpu_cap(X86_FEATURE_CLFLUSHOPT);
1174 return 1;
1175}
1176__setup("noclflush", setup_noclflush);
1177
1178void print_cpu_info(struct cpuinfo_x86 *c)
1179{
1180 const char *vendor = NULL;
1181
1182 if (c->x86_vendor < X86_VENDOR_NUM) {
1183 vendor = this_cpu->c_vendor;
1184 } else {
1185 if (c->cpuid_level >= 0)
1186 vendor = c->x86_vendor_id;
1187 }
1188
1189 if (vendor && !strstr(c->x86_model_id, vendor))
1190 pr_cont("%s ", vendor);
1191
1192 if (c->x86_model_id[0])
1193 pr_cont("%s", c->x86_model_id);
1194 else
1195 pr_cont("%d86", c->x86);
1196
1197 pr_cont(" (family: 0x%x, model: 0x%x", c->x86, c->x86_model);
1198
1199 if (c->x86_mask || c->cpuid_level >= 0)
1200 pr_cont(", stepping: 0x%x)\n", c->x86_mask);
1201 else
1202 pr_cont(")\n");
1203
1204 print_cpu_msr(c);
1205}
1206
1207void print_cpu_msr(struct cpuinfo_x86 *c)
1208{
1209 if (c->cpu_index < show_msr)
1210 __print_cpu_msr();
1211}
1212
1213static __init int setup_disablecpuid(char *arg)
1214{
1215 int bit;
1216
1217 if (get_option(&arg, &bit) && bit < NCAPINTS*32)
1218 setup_clear_cpu_cap(bit);
1219 else
1220 return 0;
1221
1222 return 1;
1223}
1224__setup("clearcpuid=", setup_disablecpuid);
1225
1226#ifdef CONFIG_X86_64
1227struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table };
1228struct desc_ptr debug_idt_descr = { NR_VECTORS * 16 - 1,
1229 (unsigned long) debug_idt_table };
1230
1231DEFINE_PER_CPU_FIRST(union irq_stack_union,
1232 irq_stack_union) __aligned(PAGE_SIZE) __visible;
1233
1234/*
1235 * The following percpu variables are hot. Align current_task to
1236 * cacheline size such that they fall in the same cacheline.
1237 */
1238DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
1239 &init_task;
1240EXPORT_PER_CPU_SYMBOL(current_task);
1241
1242DEFINE_PER_CPU(char *, irq_stack_ptr) =
1243 init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
1244
1245DEFINE_PER_CPU(unsigned int, irq_count) __visible = -1;
1246
1247DEFINE_PER_CPU(int, __preempt_count) = INIT_PREEMPT_COUNT;
1248EXPORT_PER_CPU_SYMBOL(__preempt_count);
1249
1250/*
1251 * Special IST stacks which the CPU switches to when it calls
1252 * an IST-marked descriptor entry. Up to 7 stacks (hardware
1253 * limit), all of them are 4K, except the debug stack which
1254 * is 8K.
1255 */
1256static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
1257 [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
1258 [DEBUG_STACK - 1] = DEBUG_STKSZ
1259};
1260
1261static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
1262 [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
1263
1264/* May not be marked __init: used by software suspend */
1265void syscall_init(void)
1266{
1267 /*
1268 * LSTAR and STAR live in a bit strange symbiosis.
1269 * They both write to the same internal register. STAR allows to
1270 * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
1271 */
1272 wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS);
1273 wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64);
1274
1275#ifdef CONFIG_IA32_EMULATION
1276 wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL_compat);
1277 /*
1278 * This only works on Intel CPUs.
1279 * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP.
1280 * This does not cause SYSENTER to jump to the wrong location, because
1281 * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit).
1282 */
1283 wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
1284 wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
1285 wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat);
1286#else
1287 wrmsrl(MSR_CSTAR, (unsigned long)ignore_sysret);
1288 wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG);
1289 wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL);
1290 wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL);
1291#endif
1292
1293 /* Flags to clear on syscall */
1294 wrmsrl(MSR_SYSCALL_MASK,
1295 X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|
1296 X86_EFLAGS_IOPL|X86_EFLAGS_AC|X86_EFLAGS_NT);
1297}
1298
1299/*
1300 * Copies of the original ist values from the tss are only accessed during
1301 * debugging, no special alignment required.
1302 */
1303DEFINE_PER_CPU(struct orig_ist, orig_ist);
1304
1305static DEFINE_PER_CPU(unsigned long, debug_stack_addr);
1306DEFINE_PER_CPU(int, debug_stack_usage);
1307
1308int is_debug_stack(unsigned long addr)
1309{
1310 return __this_cpu_read(debug_stack_usage) ||
1311 (addr <= __this_cpu_read(debug_stack_addr) &&
1312 addr > (__this_cpu_read(debug_stack_addr) - DEBUG_STKSZ));
1313}
1314NOKPROBE_SYMBOL(is_debug_stack);
1315
1316DEFINE_PER_CPU(u32, debug_idt_ctr);
1317
1318void debug_stack_set_zero(void)
1319{
1320 this_cpu_inc(debug_idt_ctr);
1321 load_current_idt();
1322}
1323NOKPROBE_SYMBOL(debug_stack_set_zero);
1324
1325void debug_stack_reset(void)
1326{
1327 if (WARN_ON(!this_cpu_read(debug_idt_ctr)))
1328 return;
1329 if (this_cpu_dec_return(debug_idt_ctr) == 0)
1330 load_current_idt();
1331}
1332NOKPROBE_SYMBOL(debug_stack_reset);
1333
1334#else /* CONFIG_X86_64 */
1335
1336DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
1337EXPORT_PER_CPU_SYMBOL(current_task);
1338DEFINE_PER_CPU(int, __preempt_count) = INIT_PREEMPT_COUNT;
1339EXPORT_PER_CPU_SYMBOL(__preempt_count);
1340
1341/*
1342 * On x86_32, vm86 modifies tss.sp0, so sp0 isn't a reliable way to find
1343 * the top of the kernel stack. Use an extra percpu variable to track the
1344 * top of the kernel stack directly.
1345 */
1346DEFINE_PER_CPU(unsigned long, cpu_current_top_of_stack) =
1347 (unsigned long)&init_thread_union + THREAD_SIZE;
1348EXPORT_PER_CPU_SYMBOL(cpu_current_top_of_stack);
1349
1350#ifdef CONFIG_CC_STACKPROTECTOR
1351DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
1352#endif
1353
1354#endif /* CONFIG_X86_64 */
1355
1356/*
1357 * Clear all 6 debug registers:
1358 */
1359static void clear_all_debug_regs(void)
1360{
1361 int i;
1362
1363 for (i = 0; i < 8; i++) {
1364 /* Ignore db4, db5 */
1365 if ((i == 4) || (i == 5))
1366 continue;
1367
1368 set_debugreg(0, i);
1369 }
1370}
1371
1372#ifdef CONFIG_KGDB
1373/*
1374 * Restore debug regs if using kgdbwait and you have a kernel debugger
1375 * connection established.
1376 */
1377static void dbg_restore_debug_regs(void)
1378{
1379 if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break))
1380 arch_kgdb_ops.correct_hw_break();
1381}
1382#else /* ! CONFIG_KGDB */
1383#define dbg_restore_debug_regs()
1384#endif /* ! CONFIG_KGDB */
1385
1386static void wait_for_master_cpu(int cpu)
1387{
1388#ifdef CONFIG_SMP
1389 /*
1390 * wait for ACK from master CPU before continuing
1391 * with AP initialization
1392 */
1393 WARN_ON(cpumask_test_and_set_cpu(cpu, cpu_initialized_mask));
1394 while (!cpumask_test_cpu(cpu, cpu_callout_mask))
1395 cpu_relax();
1396#endif
1397}
1398
1399/*
1400 * cpu_init() initializes state that is per-CPU. Some data is already
1401 * initialized (naturally) in the bootstrap process, such as the GDT
1402 * and IDT. We reload them nevertheless, this function acts as a
1403 * 'CPU state barrier', nothing should get across.
1404 * A lot of state is already set up in PDA init for 64 bit
1405 */
1406#ifdef CONFIG_X86_64
1407
1408void cpu_init(void)
1409{
1410 struct orig_ist *oist;
1411 struct task_struct *me;
1412 struct tss_struct *t;
1413 unsigned long v;
1414 int cpu = stack_smp_processor_id();
1415 int i;
1416
1417 wait_for_master_cpu(cpu);
1418
1419 /*
1420 * Initialize the CR4 shadow before doing anything that could
1421 * try to read it.
1422 */
1423 cr4_init_shadow();
1424
1425 /*
1426 * Load microcode on this cpu if a valid microcode is available.
1427 * This is early microcode loading procedure.
1428 */
1429 load_ucode_ap();
1430
1431 t = &per_cpu(cpu_tss, cpu);
1432 oist = &per_cpu(orig_ist, cpu);
1433
1434#ifdef CONFIG_NUMA
1435 if (this_cpu_read(numa_node) == 0 &&
1436 early_cpu_to_node(cpu) != NUMA_NO_NODE)
1437 set_numa_node(early_cpu_to_node(cpu));
1438#endif
1439
1440 me = current;
1441
1442 pr_debug("Initializing CPU#%d\n", cpu);
1443
1444 cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1445
1446 /*
1447 * Initialize the per-CPU GDT with the boot GDT,
1448 * and set up the GDT descriptor:
1449 */
1450
1451 switch_to_new_gdt(cpu);
1452 loadsegment(fs, 0);
1453
1454 load_current_idt();
1455
1456 memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
1457 syscall_init();
1458
1459 wrmsrl(MSR_FS_BASE, 0);
1460 wrmsrl(MSR_KERNEL_GS_BASE, 0);
1461 barrier();
1462
1463 x86_configure_nx();
1464 x2apic_setup();
1465
1466 /*
1467 * set up and load the per-CPU TSS
1468 */
1469 if (!oist->ist[0]) {
1470 char *estacks = per_cpu(exception_stacks, cpu);
1471
1472 for (v = 0; v < N_EXCEPTION_STACKS; v++) {
1473 estacks += exception_stack_sizes[v];
1474 oist->ist[v] = t->x86_tss.ist[v] =
1475 (unsigned long)estacks;
1476 if (v == DEBUG_STACK-1)
1477 per_cpu(debug_stack_addr, cpu) = (unsigned long)estacks;
1478 }
1479 }
1480
1481 t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
1482
1483 /*
1484 * <= is required because the CPU will access up to
1485 * 8 bits beyond the end of the IO permission bitmap.
1486 */
1487 for (i = 0; i <= IO_BITMAP_LONGS; i++)
1488 t->io_bitmap[i] = ~0UL;
1489
1490 atomic_inc(&init_mm.mm_count);
1491 me->active_mm = &init_mm;
1492 BUG_ON(me->mm);
1493 enter_lazy_tlb(&init_mm, me);
1494
1495 load_sp0(t, ¤t->thread);
1496 set_tss_desc(cpu, t);
1497 load_TR_desc();
1498 load_mm_ldt(&init_mm);
1499
1500 clear_all_debug_regs();
1501 dbg_restore_debug_regs();
1502
1503 fpu__init_cpu();
1504
1505 if (is_uv_system())
1506 uv_cpu_init();
1507}
1508
1509#else
1510
1511void cpu_init(void)
1512{
1513 int cpu = smp_processor_id();
1514 struct task_struct *curr = current;
1515 struct tss_struct *t = &per_cpu(cpu_tss, cpu);
1516 struct thread_struct *thread = &curr->thread;
1517
1518 wait_for_master_cpu(cpu);
1519
1520 /*
1521 * Initialize the CR4 shadow before doing anything that could
1522 * try to read it.
1523 */
1524 cr4_init_shadow();
1525
1526 show_ucode_info_early();
1527
1528 pr_info("Initializing CPU#%d\n", cpu);
1529
1530 if (cpu_feature_enabled(X86_FEATURE_VME) ||
1531 cpu_has_tsc ||
1532 boot_cpu_has(X86_FEATURE_DE))
1533 cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1534
1535 load_current_idt();
1536 switch_to_new_gdt(cpu);
1537
1538 /*
1539 * Set up and load the per-CPU TSS and LDT
1540 */
1541 atomic_inc(&init_mm.mm_count);
1542 curr->active_mm = &init_mm;
1543 BUG_ON(curr->mm);
1544 enter_lazy_tlb(&init_mm, curr);
1545
1546 load_sp0(t, thread);
1547 set_tss_desc(cpu, t);
1548 load_TR_desc();
1549 load_mm_ldt(&init_mm);
1550
1551 t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
1552
1553#ifdef CONFIG_DOUBLEFAULT
1554 /* Set up doublefault TSS pointer in the GDT */
1555 __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
1556#endif
1557
1558 clear_all_debug_regs();
1559 dbg_restore_debug_regs();
1560
1561 fpu__init_cpu();
1562}
1563#endif
1564
1565static void bsp_resume(void)
1566{
1567 if (this_cpu->c_bsp_resume)
1568 this_cpu->c_bsp_resume(&boot_cpu_data);
1569}
1570
1571static struct syscore_ops cpu_syscore_ops = {
1572 .resume = bsp_resume,
1573};
1574
1575static int __init init_cpu_syscore(void)
1576{
1577 register_syscore_ops(&cpu_syscore_ops);
1578 return 0;
1579}
1580core_initcall(init_cpu_syscore);