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Commit | Line | Data |
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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
2458e53f KS |
2 | /* cpu_feature_enabled() cannot be used this early */ |
3 | #define USE_EARLY_PGTABLE_L5 | |
4 | ||
57c8a661 | 5 | #include <linux/memblock.h> |
9766cdbc | 6 | #include <linux/linkage.h> |
f0fc4aff | 7 | #include <linux/bitops.h> |
9766cdbc | 8 | #include <linux/kernel.h> |
186f4360 | 9 | #include <linux/export.h> |
9766cdbc JSR |
10 | #include <linux/percpu.h> |
11 | #include <linux/string.h> | |
ee098e1a | 12 | #include <linux/ctype.h> |
1da177e4 | 13 | #include <linux/delay.h> |
68e21be2 | 14 | #include <linux/sched/mm.h> |
e6017571 | 15 | #include <linux/sched/clock.h> |
9164bb4a | 16 | #include <linux/sched/task.h> |
b47a3698 | 17 | #include <linux/sched/smt.h> |
9766cdbc | 18 | #include <linux/init.h> |
0f46efeb | 19 | #include <linux/kprobes.h> |
9766cdbc | 20 | #include <linux/kgdb.h> |
439e1757 | 21 | #include <linux/mem_encrypt.h> |
1da177e4 | 22 | #include <linux/smp.h> |
7c7077a7 | 23 | #include <linux/cpu.h> |
9766cdbc | 24 | #include <linux/io.h> |
b51ef52d | 25 | #include <linux/syscore_ops.h> |
65fddcfc | 26 | #include <linux/pgtable.h> |
b3883a9a | 27 | #include <linux/stackprotector.h> |
7c7077a7 | 28 | #include <linux/utsname.h> |
9766cdbc | 29 | |
7c7077a7 | 30 | #include <asm/alternative.h> |
1ef5423a | 31 | #include <asm/cmdline.h> |
cdd6c482 | 32 | #include <asm/perf_event.h> |
1da177e4 | 33 | #include <asm/mmu_context.h> |
dc4e0021 | 34 | #include <asm/doublefault.h> |
49d859d7 | 35 | #include <asm/archrandom.h> |
9766cdbc JSR |
36 | #include <asm/hypervisor.h> |
37 | #include <asm/processor.h> | |
1e02ce4c | 38 | #include <asm/tlbflush.h> |
f649e938 | 39 | #include <asm/debugreg.h> |
9766cdbc | 40 | #include <asm/sections.h> |
f40c3300 | 41 | #include <asm/vsyscall.h> |
8bdbd962 AC |
42 | #include <linux/topology.h> |
43 | #include <linux/cpumask.h> | |
60063497 | 44 | #include <linux/atomic.h> |
9766cdbc JSR |
45 | #include <asm/proto.h> |
46 | #include <asm/setup.h> | |
47 | #include <asm/apic.h> | |
48 | #include <asm/desc.h> | |
b56d2795 | 49 | #include <asm/fpu/api.h> |
27b07da7 | 50 | #include <asm/mtrr.h> |
0274f955 | 51 | #include <asm/hwcap2.h> |
8bdbd962 | 52 | #include <linux/numa.h> |
0cd39f46 | 53 | #include <asm/numa.h> |
9766cdbc | 54 | #include <asm/asm.h> |
0f6ff2bc | 55 | #include <asm/bugs.h> |
9766cdbc | 56 | #include <asm/cpu.h> |
a03a3e28 | 57 | #include <asm/mce.h> |
9766cdbc | 58 | #include <asm/msr.h> |
0b9a6a8b | 59 | #include <asm/cacheinfo.h> |
eb243d1d | 60 | #include <asm/memtype.h> |
d288e1cf FY |
61 | #include <asm/microcode.h> |
62 | #include <asm/microcode_intel.h> | |
fec9434a DW |
63 | #include <asm/intel-family.h> |
64 | #include <asm/cpu_device_id.h> | |
bdbcdd48 | 65 | #include <asm/uv/uv.h> |
7c7077a7 | 66 | #include <asm/set_memory.h> |
991625f3 | 67 | #include <asm/traps.h> |
95d33bfa | 68 | #include <asm/sev.h> |
1da177e4 LT |
69 | |
70 | #include "cpu.h" | |
71 | ||
0274f955 GA |
72 | u32 elf_hwcap2 __read_mostly; |
73 | ||
f8b64d08 BP |
74 | /* Number of siblings per CPU package */ |
75 | int smp_num_siblings = 1; | |
76 | EXPORT_SYMBOL(smp_num_siblings); | |
77 | ||
78 | /* Last level cache ID of each logical CPU */ | |
79 | DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id) = BAD_APICID; | |
80 | ||
9164d949 KP |
81 | u16 get_llc_id(unsigned int cpu) |
82 | { | |
83 | return per_cpu(cpu_llc_id, cpu); | |
84 | } | |
85 | EXPORT_SYMBOL_GPL(get_llc_id); | |
86 | ||
66558b73 TC |
87 | /* L2 cache ID of each logical CPU */ |
88 | DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_l2c_id) = BAD_APICID; | |
89 | ||
0dcab41d TL |
90 | static struct ppin_info { |
91 | int feature; | |
92 | int msr_ppin_ctl; | |
822ccfad | 93 | int msr_ppin; |
0dcab41d TL |
94 | } ppin_info[] = { |
95 | [X86_VENDOR_INTEL] = { | |
96 | .feature = X86_FEATURE_INTEL_PPIN, | |
97 | .msr_ppin_ctl = MSR_PPIN_CTL, | |
822ccfad | 98 | .msr_ppin = MSR_PPIN |
0dcab41d TL |
99 | }, |
100 | [X86_VENDOR_AMD] = { | |
101 | .feature = X86_FEATURE_AMD_PPIN, | |
102 | .msr_ppin_ctl = MSR_AMD_PPIN_CTL, | |
822ccfad | 103 | .msr_ppin = MSR_AMD_PPIN |
0dcab41d TL |
104 | }, |
105 | }; | |
106 | ||
107 | static const struct x86_cpu_id ppin_cpuids[] = { | |
108 | X86_MATCH_FEATURE(X86_FEATURE_AMD_PPIN, &ppin_info[X86_VENDOR_AMD]), | |
00a2f23e | 109 | X86_MATCH_FEATURE(X86_FEATURE_INTEL_PPIN, &ppin_info[X86_VENDOR_INTEL]), |
0dcab41d TL |
110 | |
111 | /* Legacy models without CPUID enumeration */ | |
112 | X86_MATCH_INTEL_FAM6_MODEL(IVYBRIDGE_X, &ppin_info[X86_VENDOR_INTEL]), | |
113 | X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X, &ppin_info[X86_VENDOR_INTEL]), | |
114 | X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_D, &ppin_info[X86_VENDOR_INTEL]), | |
115 | X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X, &ppin_info[X86_VENDOR_INTEL]), | |
116 | X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_X, &ppin_info[X86_VENDOR_INTEL]), | |
117 | X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X, &ppin_info[X86_VENDOR_INTEL]), | |
118 | X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D, &ppin_info[X86_VENDOR_INTEL]), | |
119 | X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, &ppin_info[X86_VENDOR_INTEL]), | |
36168bc0 | 120 | X86_MATCH_INTEL_FAM6_MODEL(EMERALDRAPIDS_X, &ppin_info[X86_VENDOR_INTEL]), |
0dcab41d TL |
121 | X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNL, &ppin_info[X86_VENDOR_INTEL]), |
122 | X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNM, &ppin_info[X86_VENDOR_INTEL]), | |
123 | ||
124 | {} | |
125 | }; | |
126 | ||
127 | static void ppin_init(struct cpuinfo_x86 *c) | |
128 | { | |
129 | const struct x86_cpu_id *id; | |
130 | unsigned long long val; | |
131 | struct ppin_info *info; | |
132 | ||
133 | id = x86_match_cpu(ppin_cpuids); | |
134 | if (!id) | |
135 | return; | |
136 | ||
137 | /* | |
138 | * Testing the presence of the MSR is not enough. Need to check | |
139 | * that the PPIN_CTL allows reading of the PPIN. | |
140 | */ | |
141 | info = (struct ppin_info *)id->driver_data; | |
142 | ||
143 | if (rdmsrl_safe(info->msr_ppin_ctl, &val)) | |
144 | goto clear_ppin; | |
145 | ||
146 | if ((val & 3UL) == 1UL) { | |
147 | /* PPIN locked in disabled mode */ | |
148 | goto clear_ppin; | |
149 | } | |
150 | ||
151 | /* If PPIN is disabled, try to enable */ | |
152 | if (!(val & 2UL)) { | |
153 | wrmsrl_safe(info->msr_ppin_ctl, val | 2UL); | |
154 | rdmsrl_safe(info->msr_ppin_ctl, &val); | |
155 | } | |
156 | ||
157 | /* Is the enable bit set? */ | |
158 | if (val & 2UL) { | |
822ccfad | 159 | c->ppin = __rdmsr(info->msr_ppin); |
0dcab41d TL |
160 | set_cpu_cap(c, info->feature); |
161 | return; | |
162 | } | |
163 | ||
164 | clear_ppin: | |
165 | clear_cpu_cap(c, info->feature); | |
166 | } | |
167 | ||
148f9bb8 | 168 | static void default_init(struct cpuinfo_x86 *c) |
e8055139 OZ |
169 | { |
170 | #ifdef CONFIG_X86_64 | |
27c13ece | 171 | cpu_detect_cache_sizes(c); |
e8055139 OZ |
172 | #else |
173 | /* Not much we can do here... */ | |
174 | /* Check if at least it has cpuid */ | |
175 | if (c->cpuid_level == -1) { | |
176 | /* No cpuid. It must be an ancient CPU */ | |
177 | if (c->x86 == 4) | |
178 | strcpy(c->x86_model_id, "486"); | |
179 | else if (c->x86 == 3) | |
180 | strcpy(c->x86_model_id, "386"); | |
181 | } | |
182 | #endif | |
183 | } | |
184 | ||
148f9bb8 | 185 | static const struct cpu_dev default_cpu = { |
e8055139 OZ |
186 | .c_init = default_init, |
187 | .c_vendor = "Unknown", | |
188 | .c_x86_vendor = X86_VENDOR_UNKNOWN, | |
189 | }; | |
190 | ||
148f9bb8 | 191 | static const struct cpu_dev *this_cpu = &default_cpu; |
0a488a53 | 192 | |
06deef89 | 193 | DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = { |
950ad7ff | 194 | #ifdef CONFIG_X86_64 |
06deef89 BG |
195 | /* |
196 | * We need valid kernel segments for data and code in long mode too | |
197 | * IRET will check the segment types kkeil 2000/10/28 | |
198 | * Also sysret mandates a special GDT layout | |
199 | * | |
9766cdbc | 200 | * TLS descriptors are currently at a different place compared to i386. |
06deef89 BG |
201 | * Hopefully nobody expects them at a fixed place (Wine?) |
202 | */ | |
1e5de182 AM |
203 | [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff), |
204 | [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff), | |
205 | [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff), | |
206 | [GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff), | |
207 | [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff), | |
208 | [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff), | |
950ad7ff | 209 | #else |
1e5de182 AM |
210 | [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff), |
211 | [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff), | |
212 | [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff), | |
213 | [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff), | |
bf504672 RR |
214 | /* |
215 | * Segments used for calling PnP BIOS have byte granularity. | |
216 | * They code segments and data segments have fixed 64k limits, | |
217 | * the transfer segment sizes are set at run time. | |
218 | */ | |
6842ef0e | 219 | /* 32-bit code */ |
1e5de182 | 220 | [GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(0x409a, 0, 0xffff), |
6842ef0e | 221 | /* 16-bit code */ |
1e5de182 | 222 | [GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(0x009a, 0, 0xffff), |
6842ef0e | 223 | /* 16-bit data */ |
1e5de182 | 224 | [GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(0x0092, 0, 0xffff), |
6842ef0e | 225 | /* 16-bit data */ |
1e5de182 | 226 | [GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(0x0092, 0, 0), |
6842ef0e | 227 | /* 16-bit data */ |
1e5de182 | 228 | [GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(0x0092, 0, 0), |
bf504672 RR |
229 | /* |
230 | * The APM segments have byte granularity and their bases | |
231 | * are set at run time. All have 64k limits. | |
232 | */ | |
6842ef0e | 233 | /* 32-bit code */ |
1e5de182 | 234 | [GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(0x409a, 0, 0xffff), |
bf504672 | 235 | /* 16-bit code */ |
1e5de182 | 236 | [GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff), |
6842ef0e | 237 | /* data */ |
72c4d853 | 238 | [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff), |
bf504672 | 239 | |
1e5de182 AM |
240 | [GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff), |
241 | [GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff), | |
950ad7ff | 242 | #endif |
06deef89 | 243 | } }; |
7a61d35d | 244 | EXPORT_PER_CPU_SYMBOL_GPL(gdt_page); |
ae1ee11b | 245 | |
0790c9aa | 246 | #ifdef CONFIG_X86_64 |
c7ad5ad2 | 247 | static int __init x86_nopcid_setup(char *s) |
0790c9aa | 248 | { |
c7ad5ad2 AL |
249 | /* nopcid doesn't accept parameters */ |
250 | if (s) | |
251 | return -EINVAL; | |
0790c9aa AL |
252 | |
253 | /* do not emit a message if the feature is not present */ | |
254 | if (!boot_cpu_has(X86_FEATURE_PCID)) | |
c7ad5ad2 | 255 | return 0; |
0790c9aa AL |
256 | |
257 | setup_clear_cpu_cap(X86_FEATURE_PCID); | |
258 | pr_info("nopcid: PCID feature disabled\n"); | |
c7ad5ad2 | 259 | return 0; |
0790c9aa | 260 | } |
c7ad5ad2 | 261 | early_param("nopcid", x86_nopcid_setup); |
0790c9aa AL |
262 | #endif |
263 | ||
d12a72b8 AL |
264 | static int __init x86_noinvpcid_setup(char *s) |
265 | { | |
266 | /* noinvpcid doesn't accept parameters */ | |
267 | if (s) | |
268 | return -EINVAL; | |
269 | ||
270 | /* do not emit a message if the feature is not present */ | |
271 | if (!boot_cpu_has(X86_FEATURE_INVPCID)) | |
272 | return 0; | |
273 | ||
274 | setup_clear_cpu_cap(X86_FEATURE_INVPCID); | |
275 | pr_info("noinvpcid: INVPCID feature disabled\n"); | |
276 | return 0; | |
277 | } | |
278 | early_param("noinvpcid", x86_noinvpcid_setup); | |
279 | ||
ba51dced | 280 | #ifdef CONFIG_X86_32 |
148f9bb8 PG |
281 | static int cachesize_override = -1; |
282 | static int disable_x86_serial_nr = 1; | |
1da177e4 | 283 | |
0a488a53 YL |
284 | static int __init cachesize_setup(char *str) |
285 | { | |
286 | get_option(&str, &cachesize_override); | |
287 | return 1; | |
288 | } | |
289 | __setup("cachesize=", cachesize_setup); | |
290 | ||
0a488a53 YL |
291 | /* Standard macro to see if a specific flag is changeable */ |
292 | static inline int flag_is_changeable_p(u32 flag) | |
293 | { | |
294 | u32 f1, f2; | |
295 | ||
94f6bac1 KH |
296 | /* |
297 | * Cyrix and IDT cpus allow disabling of CPUID | |
298 | * so the code below may return different results | |
299 | * when it is executed before and after enabling | |
300 | * the CPUID. Add "volatile" to not allow gcc to | |
301 | * optimize the subsequent calls to this function. | |
302 | */ | |
0f3fa48a IM |
303 | asm volatile ("pushfl \n\t" |
304 | "pushfl \n\t" | |
305 | "popl %0 \n\t" | |
306 | "movl %0, %1 \n\t" | |
307 | "xorl %2, %0 \n\t" | |
308 | "pushl %0 \n\t" | |
309 | "popfl \n\t" | |
310 | "pushfl \n\t" | |
311 | "popl %0 \n\t" | |
312 | "popfl \n\t" | |
313 | ||
94f6bac1 KH |
314 | : "=&r" (f1), "=&r" (f2) |
315 | : "ir" (flag)); | |
0a488a53 YL |
316 | |
317 | return ((f1^f2) & flag) != 0; | |
318 | } | |
319 | ||
320 | /* Probe for the CPUID instruction */ | |
148f9bb8 | 321 | int have_cpuid_p(void) |
0a488a53 YL |
322 | { |
323 | return flag_is_changeable_p(X86_EFLAGS_ID); | |
324 | } | |
325 | ||
148f9bb8 | 326 | static void squash_the_stupid_serial_number(struct cpuinfo_x86 *c) |
0a488a53 | 327 | { |
0f3fa48a IM |
328 | unsigned long lo, hi; |
329 | ||
330 | if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr) | |
331 | return; | |
332 | ||
333 | /* Disable processor serial number: */ | |
334 | ||
335 | rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi); | |
336 | lo |= 0x200000; | |
337 | wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi); | |
338 | ||
1b74dde7 | 339 | pr_notice("CPU serial number disabled.\n"); |
0f3fa48a IM |
340 | clear_cpu_cap(c, X86_FEATURE_PN); |
341 | ||
342 | /* Disabling the serial number may affect the cpuid level */ | |
343 | c->cpuid_level = cpuid_eax(0); | |
0a488a53 YL |
344 | } |
345 | ||
346 | static int __init x86_serial_nr_setup(char *s) | |
347 | { | |
348 | disable_x86_serial_nr = 0; | |
349 | return 1; | |
350 | } | |
351 | __setup("serialnumber", x86_serial_nr_setup); | |
ba51dced | 352 | #else |
102bbe3a YL |
353 | static inline int flag_is_changeable_p(u32 flag) |
354 | { | |
355 | return 1; | |
356 | } | |
102bbe3a YL |
357 | static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c) |
358 | { | |
359 | } | |
ba51dced | 360 | #endif |
0a488a53 | 361 | |
b2cc2a07 | 362 | static __always_inline void setup_smep(struct cpuinfo_x86 *c) |
de5397ad | 363 | { |
b2cc2a07 | 364 | if (cpu_has(c, X86_FEATURE_SMEP)) |
375074cc | 365 | cr4_set_bits(X86_CR4_SMEP); |
de5397ad FY |
366 | } |
367 | ||
b2cc2a07 PA |
368 | static __always_inline void setup_smap(struct cpuinfo_x86 *c) |
369 | { | |
581b7f15 | 370 | unsigned long eflags = native_save_fl(); |
b2cc2a07 PA |
371 | |
372 | /* This should have been cleared long ago */ | |
b2cc2a07 PA |
373 | BUG_ON(eflags & X86_EFLAGS_AC); |
374 | ||
dbae0a93 | 375 | if (cpu_has(c, X86_FEATURE_SMAP)) |
375074cc | 376 | cr4_set_bits(X86_CR4_SMAP); |
de5397ad FY |
377 | } |
378 | ||
aa35f896 RN |
379 | static __always_inline void setup_umip(struct cpuinfo_x86 *c) |
380 | { | |
381 | /* Check the boot processor, plus build option for UMIP. */ | |
382 | if (!cpu_feature_enabled(X86_FEATURE_UMIP)) | |
383 | goto out; | |
384 | ||
385 | /* Check the current processor's cpuid bits. */ | |
386 | if (!cpu_has(c, X86_FEATURE_UMIP)) | |
387 | goto out; | |
388 | ||
389 | cr4_set_bits(X86_CR4_UMIP); | |
390 | ||
438cbf88 | 391 | pr_info_once("x86/cpu: User Mode Instruction Prevention (UMIP) activated\n"); |
770c7755 | 392 | |
aa35f896 RN |
393 | return; |
394 | ||
395 | out: | |
396 | /* | |
397 | * Make sure UMIP is disabled in case it was enabled in a | |
398 | * previous boot (e.g., via kexec). | |
399 | */ | |
400 | cr4_clear_bits(X86_CR4_UMIP); | |
401 | } | |
402 | ||
a13b9d0b KC |
403 | /* These bits should not change their value after CPU init is finished. */ |
404 | static const unsigned long cr4_pinned_mask = | |
991625f3 PZ |
405 | X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_UMIP | |
406 | X86_CR4_FSGSBASE | X86_CR4_CET; | |
7652ac92 TG |
407 | static DEFINE_STATIC_KEY_FALSE_RO(cr_pinning); |
408 | static unsigned long cr4_pinned_bits __ro_after_init; | |
409 | ||
410 | void native_write_cr0(unsigned long val) | |
411 | { | |
412 | unsigned long bits_missing = 0; | |
413 | ||
414 | set_register: | |
aa5cacdc | 415 | asm volatile("mov %0,%%cr0": "+r" (val) : : "memory"); |
7652ac92 TG |
416 | |
417 | if (static_branch_likely(&cr_pinning)) { | |
418 | if (unlikely((val & X86_CR0_WP) != X86_CR0_WP)) { | |
419 | bits_missing = X86_CR0_WP; | |
420 | val |= bits_missing; | |
421 | goto set_register; | |
422 | } | |
423 | /* Warn after we've set the missing bits. */ | |
424 | WARN_ONCE(bits_missing, "CR0 WP bit went missing!?\n"); | |
425 | } | |
426 | } | |
427 | EXPORT_SYMBOL(native_write_cr0); | |
428 | ||
b64dfcde | 429 | void __no_profile native_write_cr4(unsigned long val) |
7652ac92 | 430 | { |
a13b9d0b | 431 | unsigned long bits_changed = 0; |
7652ac92 TG |
432 | |
433 | set_register: | |
aa5cacdc | 434 | asm volatile("mov %0,%%cr4": "+r" (val) : : "memory"); |
7652ac92 TG |
435 | |
436 | if (static_branch_likely(&cr_pinning)) { | |
a13b9d0b KC |
437 | if (unlikely((val & cr4_pinned_mask) != cr4_pinned_bits)) { |
438 | bits_changed = (val & cr4_pinned_mask) ^ cr4_pinned_bits; | |
439 | val = (val & ~cr4_pinned_mask) | cr4_pinned_bits; | |
7652ac92 TG |
440 | goto set_register; |
441 | } | |
a13b9d0b KC |
442 | /* Warn after we've corrected the changed bits. */ |
443 | WARN_ONCE(bits_changed, "pinned CR4 bits changed: 0x%lx!?\n", | |
444 | bits_changed); | |
7652ac92 TG |
445 | } |
446 | } | |
21953ee5 | 447 | #if IS_MODULE(CONFIG_LKDTM) |
d8f0b353 | 448 | EXPORT_SYMBOL_GPL(native_write_cr4); |
21953ee5 | 449 | #endif |
d8f0b353 TG |
450 | |
451 | void cr4_update_irqsoff(unsigned long set, unsigned long clear) | |
452 | { | |
453 | unsigned long newval, cr4 = this_cpu_read(cpu_tlbstate.cr4); | |
454 | ||
455 | lockdep_assert_irqs_disabled(); | |
456 | ||
457 | newval = (cr4 & ~clear) | set; | |
458 | if (newval != cr4) { | |
459 | this_cpu_write(cpu_tlbstate.cr4, newval); | |
460 | __write_cr4(newval); | |
461 | } | |
462 | } | |
463 | EXPORT_SYMBOL(cr4_update_irqsoff); | |
464 | ||
465 | /* Read the CR4 shadow. */ | |
466 | unsigned long cr4_read_shadow(void) | |
467 | { | |
468 | return this_cpu_read(cpu_tlbstate.cr4); | |
469 | } | |
470 | EXPORT_SYMBOL_GPL(cr4_read_shadow); | |
7652ac92 TG |
471 | |
472 | void cr4_init(void) | |
473 | { | |
474 | unsigned long cr4 = __read_cr4(); | |
475 | ||
476 | if (boot_cpu_has(X86_FEATURE_PCID)) | |
477 | cr4 |= X86_CR4_PCIDE; | |
478 | if (static_branch_likely(&cr_pinning)) | |
a13b9d0b | 479 | cr4 = (cr4 & ~cr4_pinned_mask) | cr4_pinned_bits; |
7652ac92 TG |
480 | |
481 | __write_cr4(cr4); | |
482 | ||
483 | /* Initialize cr4 shadow for this CPU. */ | |
484 | this_cpu_write(cpu_tlbstate.cr4, cr4); | |
485 | } | |
873d50d5 KC |
486 | |
487 | /* | |
488 | * Once CPU feature detection is finished (and boot params have been | |
489 | * parsed), record any of the sensitive CR bits that are set, and | |
490 | * enable CR pinning. | |
491 | */ | |
492 | static void __init setup_cr_pinning(void) | |
493 | { | |
a13b9d0b | 494 | cr4_pinned_bits = this_cpu_read(cpu_tlbstate.cr4) & cr4_pinned_mask; |
873d50d5 KC |
495 | static_key_enable(&cr_pinning.key); |
496 | } | |
497 | ||
b745cfba | 498 | static __init int x86_nofsgsbase_setup(char *arg) |
dd649bd0 | 499 | { |
b745cfba AL |
500 | /* Require an exact match without trailing characters. */ |
501 | if (strlen(arg)) | |
502 | return 0; | |
503 | ||
504 | /* Do not emit a message if the feature is not present. */ | |
505 | if (!boot_cpu_has(X86_FEATURE_FSGSBASE)) | |
506 | return 1; | |
507 | ||
508 | setup_clear_cpu_cap(X86_FEATURE_FSGSBASE); | |
509 | pr_info("FSGSBASE disabled via kernel command line\n"); | |
dd649bd0 AL |
510 | return 1; |
511 | } | |
b745cfba | 512 | __setup("nofsgsbase", x86_nofsgsbase_setup); |
dd649bd0 | 513 | |
06976945 DH |
514 | /* |
515 | * Protection Keys are not available in 32-bit mode. | |
516 | */ | |
517 | static bool pku_disabled; | |
518 | ||
519 | static __always_inline void setup_pku(struct cpuinfo_x86 *c) | |
520 | { | |
8a1dc55a TG |
521 | if (c == &boot_cpu_data) { |
522 | if (pku_disabled || !cpu_feature_enabled(X86_FEATURE_PKU)) | |
523 | return; | |
524 | /* | |
525 | * Setting CR4.PKE will cause the X86_FEATURE_OSPKE cpuid | |
526 | * bit to be set. Enforce it. | |
527 | */ | |
528 | setup_force_cpu_cap(X86_FEATURE_OSPKE); | |
a5eff725 | 529 | |
8a1dc55a | 530 | } else if (!cpu_feature_enabled(X86_FEATURE_OSPKE)) { |
06976945 | 531 | return; |
8a1dc55a | 532 | } |
06976945 DH |
533 | |
534 | cr4_set_bits(X86_CR4_PKE); | |
fa8c84b7 TG |
535 | /* Load the default PKRU value */ |
536 | pkru_write_default(); | |
06976945 DH |
537 | } |
538 | ||
539 | #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS | |
540 | static __init int setup_disable_pku(char *arg) | |
541 | { | |
542 | /* | |
543 | * Do not clear the X86_FEATURE_PKU bit. All of the | |
544 | * runtime checks are against OSPKE so clearing the | |
545 | * bit does nothing. | |
546 | * | |
547 | * This way, we will see "pku" in cpuinfo, but not | |
548 | * "ospke", which is exactly what we want. It shows | |
549 | * that the CPU has PKU, but the OS has not enabled it. | |
550 | * This happens to be exactly how a system would look | |
551 | * if we disabled the config option. | |
552 | */ | |
553 | pr_info("x86: 'nopku' specified, disabling Memory Protection Keys\n"); | |
554 | pku_disabled = true; | |
555 | return 1; | |
556 | } | |
557 | __setup("nopku", setup_disable_pku); | |
d55dcb73 | 558 | #endif |
06976945 | 559 | |
fe379fa4 PZ |
560 | #ifdef CONFIG_X86_KERNEL_IBT |
561 | ||
93be2859 | 562 | __noendbr u64 ibt_save(bool disable) |
fe379fa4 PZ |
563 | { |
564 | u64 msr = 0; | |
565 | ||
566 | if (cpu_feature_enabled(X86_FEATURE_IBT)) { | |
567 | rdmsrl(MSR_IA32_S_CET, msr); | |
93be2859 AB |
568 | if (disable) |
569 | wrmsrl(MSR_IA32_S_CET, msr & ~CET_ENDBR_EN); | |
fe379fa4 PZ |
570 | } |
571 | ||
572 | return msr; | |
573 | } | |
574 | ||
575 | __noendbr void ibt_restore(u64 save) | |
576 | { | |
577 | u64 msr; | |
578 | ||
579 | if (cpu_feature_enabled(X86_FEATURE_IBT)) { | |
580 | rdmsrl(MSR_IA32_S_CET, msr); | |
581 | msr &= ~CET_ENDBR_EN; | |
582 | msr |= (save & CET_ENDBR_EN); | |
583 | wrmsrl(MSR_IA32_S_CET, msr); | |
584 | } | |
585 | } | |
586 | ||
587 | #endif | |
588 | ||
991625f3 PZ |
589 | static __always_inline void setup_cet(struct cpuinfo_x86 *c) |
590 | { | |
591 | u64 msr = CET_ENDBR_EN; | |
592 | ||
593 | if (!HAS_KERNEL_IBT || | |
594 | !cpu_feature_enabled(X86_FEATURE_IBT)) | |
595 | return; | |
596 | ||
597 | wrmsrl(MSR_IA32_S_CET, msr); | |
598 | cr4_set_bits(X86_CR4_CET); | |
599 | ||
600 | if (!ibt_selftest()) { | |
601 | pr_err("IBT selftest: Failed!\n"); | |
931ab636 | 602 | wrmsrl(MSR_IA32_S_CET, 0); |
991625f3 PZ |
603 | setup_clear_cpu_cap(X86_FEATURE_IBT); |
604 | return; | |
605 | } | |
606 | } | |
607 | ||
af227003 PZ |
608 | __noendbr void cet_disable(void) |
609 | { | |
610 | if (cpu_feature_enabled(X86_FEATURE_IBT)) | |
611 | wrmsrl(MSR_IA32_S_CET, 0); | |
612 | } | |
613 | ||
b38b0665 PA |
614 | /* |
615 | * Some CPU features depend on higher CPUID levels, which may not always | |
616 | * be available due to CPUID level capping or broken virtualization | |
617 | * software. Add those features to this table to auto-disable them. | |
618 | */ | |
619 | struct cpuid_dependent_feature { | |
620 | u32 feature; | |
621 | u32 level; | |
622 | }; | |
0f3fa48a | 623 | |
148f9bb8 | 624 | static const struct cpuid_dependent_feature |
b38b0665 PA |
625 | cpuid_dependent_features[] = { |
626 | { X86_FEATURE_MWAIT, 0x00000005 }, | |
627 | { X86_FEATURE_DCA, 0x00000009 }, | |
628 | { X86_FEATURE_XSAVE, 0x0000000d }, | |
629 | { 0, 0 } | |
630 | }; | |
631 | ||
148f9bb8 | 632 | static void filter_cpuid_features(struct cpuinfo_x86 *c, bool warn) |
b38b0665 PA |
633 | { |
634 | const struct cpuid_dependent_feature *df; | |
9766cdbc | 635 | |
b38b0665 | 636 | for (df = cpuid_dependent_features; df->feature; df++) { |
0f3fa48a IM |
637 | |
638 | if (!cpu_has(c, df->feature)) | |
639 | continue; | |
b38b0665 PA |
640 | /* |
641 | * Note: cpuid_level is set to -1 if unavailable, but | |
642 | * extended_extended_level is set to 0 if unavailable | |
643 | * and the legitimate extended levels are all negative | |
644 | * when signed; hence the weird messing around with | |
645 | * signs here... | |
646 | */ | |
0f3fa48a | 647 | if (!((s32)df->level < 0 ? |
f6db44df | 648 | (u32)df->level > (u32)c->extended_cpuid_level : |
0f3fa48a IM |
649 | (s32)df->level > (s32)c->cpuid_level)) |
650 | continue; | |
651 | ||
652 | clear_cpu_cap(c, df->feature); | |
653 | if (!warn) | |
654 | continue; | |
655 | ||
1b74dde7 CY |
656 | pr_warn("CPU: CPU feature " X86_CAP_FMT " disabled, no CPUID level 0x%x\n", |
657 | x86_cap_flag(df->feature), df->level); | |
b38b0665 | 658 | } |
f6db44df | 659 | } |
b38b0665 | 660 | |
102bbe3a YL |
661 | /* |
662 | * Naming convention should be: <Name> [(<Codename>)] | |
663 | * This table only is used unless init_<vendor>() below doesn't set it; | |
0f3fa48a IM |
664 | * in particular, if CPUID levels 0x80000002..4 are supported, this |
665 | * isn't used | |
102bbe3a YL |
666 | */ |
667 | ||
668 | /* Look up CPU names by table lookup. */ | |
148f9bb8 | 669 | static const char *table_lookup_model(struct cpuinfo_x86 *c) |
102bbe3a | 670 | { |
09dc68d9 JB |
671 | #ifdef CONFIG_X86_32 |
672 | const struct legacy_cpu_model_info *info; | |
102bbe3a YL |
673 | |
674 | if (c->x86_model >= 16) | |
675 | return NULL; /* Range check */ | |
676 | ||
677 | if (!this_cpu) | |
678 | return NULL; | |
679 | ||
09dc68d9 | 680 | info = this_cpu->legacy_models; |
102bbe3a | 681 | |
09dc68d9 | 682 | while (info->family) { |
102bbe3a YL |
683 | if (info->family == c->x86) |
684 | return info->model_names[c->x86_model]; | |
685 | info++; | |
686 | } | |
09dc68d9 | 687 | #endif |
102bbe3a YL |
688 | return NULL; /* Not found */ |
689 | } | |
690 | ||
f6a892dd FY |
691 | /* Aligned to unsigned long to avoid split lock in atomic bitmap ops */ |
692 | __u32 cpu_caps_cleared[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long)); | |
693 | __u32 cpu_caps_set[NCAPINTS + NBUGINTS] __aligned(sizeof(unsigned long)); | |
7d851c8d | 694 | |
72f5e08d AL |
695 | #ifdef CONFIG_X86_32 |
696 | /* The 32-bit entry code needs to find cpu_entry_area. */ | |
697 | DEFINE_PER_CPU(struct cpu_entry_area *, cpu_entry_area); | |
698 | #endif | |
699 | ||
45fc8757 TG |
700 | /* Load the original GDT from the per-cpu structure */ |
701 | void load_direct_gdt(int cpu) | |
702 | { | |
703 | struct desc_ptr gdt_descr; | |
704 | ||
705 | gdt_descr.address = (long)get_cpu_gdt_rw(cpu); | |
706 | gdt_descr.size = GDT_SIZE - 1; | |
707 | load_gdt(&gdt_descr); | |
708 | } | |
709 | EXPORT_SYMBOL_GPL(load_direct_gdt); | |
710 | ||
69218e47 TG |
711 | /* Load a fixmap remapping of the per-cpu GDT */ |
712 | void load_fixmap_gdt(int cpu) | |
713 | { | |
714 | struct desc_ptr gdt_descr; | |
715 | ||
716 | gdt_descr.address = (long)get_cpu_gdt_ro(cpu); | |
717 | gdt_descr.size = GDT_SIZE - 1; | |
718 | load_gdt(&gdt_descr); | |
719 | } | |
45fc8757 | 720 | EXPORT_SYMBOL_GPL(load_fixmap_gdt); |
69218e47 | 721 | |
b5636d45 | 722 | /** |
1f19e2d5 | 723 | * switch_gdt_and_percpu_base - Switch to direct GDT and runtime per CPU base |
b5636d45 TG |
724 | * @cpu: The CPU number for which this is invoked |
725 | * | |
1f19e2d5 TG |
726 | * Invoked during early boot to switch from early GDT and early per CPU to |
727 | * the direct GDT and the runtime per CPU area. On 32-bit the percpu base | |
728 | * switch is implicit by loading the direct GDT. On 64bit this requires | |
729 | * to update GSBASE. | |
0f3fa48a | 730 | */ |
1f19e2d5 | 731 | void __init switch_gdt_and_percpu_base(int cpu) |
9d31d35b | 732 | { |
45fc8757 | 733 | load_direct_gdt(cpu); |
b5636d45 TG |
734 | |
735 | #ifdef CONFIG_X86_64 | |
736 | /* | |
737 | * No need to load %gs. It is already correct. | |
738 | * | |
739 | * Writing %gs on 64bit would zero GSBASE which would make any per | |
740 | * CPU operation up to the point of the wrmsrl() fault. | |
741 | * | |
742 | * Set GSBASE to the new offset. Until the wrmsrl() happens the | |
743 | * early mapping is still valid. That means the GSBASE update will | |
744 | * lose any prior per CPU data which was not copied over in | |
745 | * setup_per_cpu_areas(). | |
2cb15faa TG |
746 | * |
747 | * This works even with stackprotector enabled because the | |
748 | * per CPU stack canary is 0 in both per CPU areas. | |
b5636d45 TG |
749 | */ |
750 | wrmsrl(MSR_GS_BASE, cpu_kernelmode_gs_base(cpu)); | |
751 | #else | |
752 | /* | |
753 | * %fs is already set to __KERNEL_PERCPU, but after switching GDT | |
754 | * it is required to load FS again so that the 'hidden' part is | |
755 | * updated from the new GDT. Up to this point the early per CPU | |
756 | * translation is active. Any content of the early per CPU data | |
757 | * which was not copied over in setup_per_cpu_areas() is lost. | |
758 | */ | |
759 | loadsegment(fs, __KERNEL_PERCPU); | |
760 | #endif | |
9d31d35b YL |
761 | } |
762 | ||
148f9bb8 | 763 | static const struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {}; |
1da177e4 | 764 | |
148f9bb8 | 765 | static void get_model_name(struct cpuinfo_x86 *c) |
1da177e4 LT |
766 | { |
767 | unsigned int *v; | |
ee098e1a | 768 | char *p, *q, *s; |
1da177e4 | 769 | |
3da99c97 | 770 | if (c->extended_cpuid_level < 0x80000004) |
1b05d60d | 771 | return; |
1da177e4 | 772 | |
0f3fa48a | 773 | v = (unsigned int *)c->x86_model_id; |
1da177e4 LT |
774 | cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]); |
775 | cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]); | |
776 | cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]); | |
777 | c->x86_model_id[48] = 0; | |
778 | ||
ee098e1a BP |
779 | /* Trim whitespace */ |
780 | p = q = s = &c->x86_model_id[0]; | |
781 | ||
782 | while (*p == ' ') | |
783 | p++; | |
784 | ||
785 | while (*p) { | |
786 | /* Note the last non-whitespace index */ | |
787 | if (!isspace(*p)) | |
788 | s = q; | |
789 | ||
790 | *q++ = *p++; | |
791 | } | |
792 | ||
793 | *(s + 1) = '\0'; | |
1da177e4 LT |
794 | } |
795 | ||
9305bd6c | 796 | void detect_num_cpu_cores(struct cpuinfo_x86 *c) |
2cc61be6 DW |
797 | { |
798 | unsigned int eax, ebx, ecx, edx; | |
799 | ||
9305bd6c | 800 | c->x86_max_cores = 1; |
2cc61be6 | 801 | if (!IS_ENABLED(CONFIG_SMP) || c->cpuid_level < 4) |
9305bd6c | 802 | return; |
2cc61be6 DW |
803 | |
804 | cpuid_count(4, 0, &eax, &ebx, &ecx, &edx); | |
805 | if (eax & 0x1f) | |
9305bd6c | 806 | c->x86_max_cores = (eax >> 26) + 1; |
2cc61be6 DW |
807 | } |
808 | ||
148f9bb8 | 809 | void cpu_detect_cache_sizes(struct cpuinfo_x86 *c) |
1da177e4 | 810 | { |
9d31d35b | 811 | unsigned int n, dummy, ebx, ecx, edx, l2size; |
1da177e4 | 812 | |
3da99c97 | 813 | n = c->extended_cpuid_level; |
1da177e4 LT |
814 | |
815 | if (n >= 0x80000005) { | |
9d31d35b | 816 | cpuid(0x80000005, &dummy, &ebx, &ecx, &edx); |
9d31d35b | 817 | c->x86_cache_size = (ecx>>24) + (edx>>24); |
140fc727 YL |
818 | #ifdef CONFIG_X86_64 |
819 | /* On K8 L1 TLB is inclusive, so don't count it */ | |
820 | c->x86_tlbsize = 0; | |
821 | #endif | |
1da177e4 LT |
822 | } |
823 | ||
824 | if (n < 0x80000006) /* Some chips just has a large L1. */ | |
825 | return; | |
826 | ||
0a488a53 | 827 | cpuid(0x80000006, &dummy, &ebx, &ecx, &edx); |
1da177e4 | 828 | l2size = ecx >> 16; |
34048c9e | 829 | |
140fc727 YL |
830 | #ifdef CONFIG_X86_64 |
831 | c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff); | |
832 | #else | |
1da177e4 | 833 | /* do processor-specific cache resizing */ |
09dc68d9 JB |
834 | if (this_cpu->legacy_cache_size) |
835 | l2size = this_cpu->legacy_cache_size(c, l2size); | |
1da177e4 LT |
836 | |
837 | /* Allow user to override all this if necessary. */ | |
838 | if (cachesize_override != -1) | |
839 | l2size = cachesize_override; | |
840 | ||
34048c9e | 841 | if (l2size == 0) |
1da177e4 | 842 | return; /* Again, no L2 cache is possible */ |
140fc727 | 843 | #endif |
1da177e4 LT |
844 | |
845 | c->x86_cache_size = l2size; | |
1da177e4 LT |
846 | } |
847 | ||
e0ba94f1 AS |
848 | u16 __read_mostly tlb_lli_4k[NR_INFO]; |
849 | u16 __read_mostly tlb_lli_2m[NR_INFO]; | |
850 | u16 __read_mostly tlb_lli_4m[NR_INFO]; | |
851 | u16 __read_mostly tlb_lld_4k[NR_INFO]; | |
852 | u16 __read_mostly tlb_lld_2m[NR_INFO]; | |
853 | u16 __read_mostly tlb_lld_4m[NR_INFO]; | |
dd360393 | 854 | u16 __read_mostly tlb_lld_1g[NR_INFO]; |
e0ba94f1 | 855 | |
f94fe119 | 856 | static void cpu_detect_tlb(struct cpuinfo_x86 *c) |
e0ba94f1 AS |
857 | { |
858 | if (this_cpu->c_detect_tlb) | |
859 | this_cpu->c_detect_tlb(c); | |
860 | ||
f94fe119 | 861 | pr_info("Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n", |
e0ba94f1 | 862 | tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES], |
f94fe119 SH |
863 | tlb_lli_4m[ENTRIES]); |
864 | ||
865 | pr_info("Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d, 1GB %d\n", | |
866 | tlb_lld_4k[ENTRIES], tlb_lld_2m[ENTRIES], | |
867 | tlb_lld_4m[ENTRIES], tlb_lld_1g[ENTRIES]); | |
e0ba94f1 AS |
868 | } |
869 | ||
545401f4 | 870 | int detect_ht_early(struct cpuinfo_x86 *c) |
1da177e4 | 871 | { |
c8e56d20 | 872 | #ifdef CONFIG_SMP |
0a488a53 | 873 | u32 eax, ebx, ecx, edx; |
1da177e4 | 874 | |
0a488a53 | 875 | if (!cpu_has(c, X86_FEATURE_HT)) |
545401f4 | 876 | return -1; |
1da177e4 | 877 | |
0a488a53 | 878 | if (cpu_has(c, X86_FEATURE_CMP_LEGACY)) |
545401f4 | 879 | return -1; |
1da177e4 | 880 | |
1cd78776 | 881 | if (cpu_has(c, X86_FEATURE_XTOPOLOGY)) |
545401f4 | 882 | return -1; |
1da177e4 | 883 | |
0a488a53 | 884 | cpuid(1, &eax, &ebx, &ecx, &edx); |
1da177e4 | 885 | |
9d31d35b | 886 | smp_num_siblings = (ebx & 0xff0000) >> 16; |
545401f4 | 887 | if (smp_num_siblings == 1) |
1b74dde7 | 888 | pr_info_once("CPU0: Hyper-Threading is disabled\n"); |
545401f4 TG |
889 | #endif |
890 | return 0; | |
891 | } | |
9d31d35b | 892 | |
545401f4 TG |
893 | void detect_ht(struct cpuinfo_x86 *c) |
894 | { | |
895 | #ifdef CONFIG_SMP | |
896 | int index_msb, core_bits; | |
55e6d279 | 897 | |
545401f4 | 898 | if (detect_ht_early(c) < 0) |
55e6d279 | 899 | return; |
9d31d35b | 900 | |
0f3fa48a IM |
901 | index_msb = get_count_order(smp_num_siblings); |
902 | c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb); | |
9d31d35b | 903 | |
0f3fa48a | 904 | smp_num_siblings = smp_num_siblings / c->x86_max_cores; |
9d31d35b | 905 | |
0f3fa48a | 906 | index_msb = get_count_order(smp_num_siblings); |
9d31d35b | 907 | |
0f3fa48a | 908 | core_bits = get_count_order(c->x86_max_cores); |
9d31d35b | 909 | |
0f3fa48a IM |
910 | c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) & |
911 | ((1 << core_bits) - 1); | |
9d31d35b | 912 | #endif |
97e4db7c | 913 | } |
1da177e4 | 914 | |
148f9bb8 | 915 | static void get_cpu_vendor(struct cpuinfo_x86 *c) |
1da177e4 LT |
916 | { |
917 | char *v = c->x86_vendor_id; | |
0f3fa48a | 918 | int i; |
1da177e4 LT |
919 | |
920 | for (i = 0; i < X86_VENDOR_NUM; i++) { | |
10a434fc YL |
921 | if (!cpu_devs[i]) |
922 | break; | |
923 | ||
924 | if (!strcmp(v, cpu_devs[i]->c_ident[0]) || | |
925 | (cpu_devs[i]->c_ident[1] && | |
926 | !strcmp(v, cpu_devs[i]->c_ident[1]))) { | |
0f3fa48a | 927 | |
10a434fc YL |
928 | this_cpu = cpu_devs[i]; |
929 | c->x86_vendor = this_cpu->c_x86_vendor; | |
930 | return; | |
1da177e4 LT |
931 | } |
932 | } | |
10a434fc | 933 | |
1b74dde7 CY |
934 | pr_err_once("CPU: vendor_id '%s' unknown, using generic init.\n" \ |
935 | "CPU: Your system may be unstable.\n", v); | |
10a434fc | 936 | |
fe38d855 CE |
937 | c->x86_vendor = X86_VENDOR_UNKNOWN; |
938 | this_cpu = &default_cpu; | |
1da177e4 LT |
939 | } |
940 | ||
148f9bb8 | 941 | void cpu_detect(struct cpuinfo_x86 *c) |
1da177e4 | 942 | { |
1da177e4 | 943 | /* Get vendor name */ |
4a148513 HH |
944 | cpuid(0x00000000, (unsigned int *)&c->cpuid_level, |
945 | (unsigned int *)&c->x86_vendor_id[0], | |
946 | (unsigned int *)&c->x86_vendor_id[8], | |
947 | (unsigned int *)&c->x86_vendor_id[4]); | |
1da177e4 | 948 | |
1da177e4 | 949 | c->x86 = 4; |
9d31d35b | 950 | /* Intel-defined flags: level 0x00000001 */ |
1da177e4 LT |
951 | if (c->cpuid_level >= 0x00000001) { |
952 | u32 junk, tfms, cap0, misc; | |
0f3fa48a | 953 | |
1da177e4 | 954 | cpuid(0x00000001, &tfms, &misc, &junk, &cap0); |
99f925ce BP |
955 | c->x86 = x86_family(tfms); |
956 | c->x86_model = x86_model(tfms); | |
b399151c | 957 | c->x86_stepping = x86_stepping(tfms); |
0f3fa48a | 958 | |
d4387bd3 | 959 | if (cap0 & (1<<19)) { |
d4387bd3 | 960 | c->x86_clflush_size = ((misc >> 8) & 0xff) * 8; |
9d31d35b | 961 | c->x86_cache_alignment = c->x86_clflush_size; |
d4387bd3 | 962 | } |
1da177e4 | 963 | } |
1da177e4 | 964 | } |
3da99c97 | 965 | |
8bf1ebca AL |
966 | static void apply_forced_caps(struct cpuinfo_x86 *c) |
967 | { | |
968 | int i; | |
969 | ||
6cbd2171 | 970 | for (i = 0; i < NCAPINTS + NBUGINTS; i++) { |
8bf1ebca AL |
971 | c->x86_capability[i] &= ~cpu_caps_cleared[i]; |
972 | c->x86_capability[i] |= cpu_caps_set[i]; | |
973 | } | |
974 | } | |
975 | ||
7fcae111 DW |
976 | static void init_speculation_control(struct cpuinfo_x86 *c) |
977 | { | |
978 | /* | |
979 | * The Intel SPEC_CTRL CPUID bit implies IBRS and IBPB support, | |
980 | * and they also have a different bit for STIBP support. Also, | |
981 | * a hypervisor might have set the individual AMD bits even on | |
982 | * Intel CPUs, for finer-grained selection of what's available. | |
7fcae111 DW |
983 | */ |
984 | if (cpu_has(c, X86_FEATURE_SPEC_CTRL)) { | |
985 | set_cpu_cap(c, X86_FEATURE_IBRS); | |
986 | set_cpu_cap(c, X86_FEATURE_IBPB); | |
7eb8956a | 987 | set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL); |
7fcae111 | 988 | } |
e7c587da | 989 | |
7fcae111 DW |
990 | if (cpu_has(c, X86_FEATURE_INTEL_STIBP)) |
991 | set_cpu_cap(c, X86_FEATURE_STIBP); | |
e7c587da | 992 | |
bc226f07 TL |
993 | if (cpu_has(c, X86_FEATURE_SPEC_CTRL_SSBD) || |
994 | cpu_has(c, X86_FEATURE_VIRT_SSBD)) | |
52817587 TG |
995 | set_cpu_cap(c, X86_FEATURE_SSBD); |
996 | ||
7eb8956a | 997 | if (cpu_has(c, X86_FEATURE_AMD_IBRS)) { |
e7c587da | 998 | set_cpu_cap(c, X86_FEATURE_IBRS); |
7eb8956a TG |
999 | set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL); |
1000 | } | |
e7c587da BP |
1001 | |
1002 | if (cpu_has(c, X86_FEATURE_AMD_IBPB)) | |
1003 | set_cpu_cap(c, X86_FEATURE_IBPB); | |
1004 | ||
7eb8956a | 1005 | if (cpu_has(c, X86_FEATURE_AMD_STIBP)) { |
e7c587da | 1006 | set_cpu_cap(c, X86_FEATURE_STIBP); |
7eb8956a TG |
1007 | set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL); |
1008 | } | |
6ac2f49e KRW |
1009 | |
1010 | if (cpu_has(c, X86_FEATURE_AMD_SSBD)) { | |
1011 | set_cpu_cap(c, X86_FEATURE_SSBD); | |
1012 | set_cpu_cap(c, X86_FEATURE_MSR_SPEC_CTRL); | |
1013 | clear_cpu_cap(c, X86_FEATURE_VIRT_SSBD); | |
1014 | } | |
7fcae111 DW |
1015 | } |
1016 | ||
148f9bb8 | 1017 | void get_cpu_cap(struct cpuinfo_x86 *c) |
093af8d7 | 1018 | { |
39c06df4 | 1019 | u32 eax, ebx, ecx, edx; |
093af8d7 | 1020 | |
3da99c97 YL |
1021 | /* Intel-defined flags: level 0x00000001 */ |
1022 | if (c->cpuid_level >= 0x00000001) { | |
39c06df4 | 1023 | cpuid(0x00000001, &eax, &ebx, &ecx, &edx); |
0f3fa48a | 1024 | |
39c06df4 BP |
1025 | c->x86_capability[CPUID_1_ECX] = ecx; |
1026 | c->x86_capability[CPUID_1_EDX] = edx; | |
3da99c97 | 1027 | } |
093af8d7 | 1028 | |
3df8d920 AL |
1029 | /* Thermal and Power Management Leaf: level 0x00000006 (eax) */ |
1030 | if (c->cpuid_level >= 0x00000006) | |
1031 | c->x86_capability[CPUID_6_EAX] = cpuid_eax(0x00000006); | |
1032 | ||
bdc802dc PA |
1033 | /* Additional Intel-defined flags: level 0x00000007 */ |
1034 | if (c->cpuid_level >= 0x00000007) { | |
bdc802dc | 1035 | cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx); |
39c06df4 | 1036 | c->x86_capability[CPUID_7_0_EBX] = ebx; |
dfb4a70f | 1037 | c->x86_capability[CPUID_7_ECX] = ecx; |
95ca0ee8 | 1038 | c->x86_capability[CPUID_7_EDX] = edx; |
b302e4b1 FY |
1039 | |
1040 | /* Check valid sub-leaf index before accessing it */ | |
1041 | if (eax >= 1) { | |
1042 | cpuid_count(0x00000007, 1, &eax, &ebx, &ecx, &edx); | |
1043 | c->x86_capability[CPUID_7_1_EAX] = eax; | |
1044 | } | |
bdc802dc PA |
1045 | } |
1046 | ||
6229ad27 FY |
1047 | /* Extended state features: level 0x0000000d */ |
1048 | if (c->cpuid_level >= 0x0000000d) { | |
6229ad27 FY |
1049 | cpuid_count(0x0000000d, 1, &eax, &ebx, &ecx, &edx); |
1050 | ||
39c06df4 | 1051 | c->x86_capability[CPUID_D_1_EAX] = eax; |
6229ad27 FY |
1052 | } |
1053 | ||
3da99c97 | 1054 | /* AMD-defined flags: level 0x80000001 */ |
39c06df4 BP |
1055 | eax = cpuid_eax(0x80000000); |
1056 | c->extended_cpuid_level = eax; | |
1057 | ||
1058 | if ((eax & 0xffff0000) == 0x80000000) { | |
1059 | if (eax >= 0x80000001) { | |
1060 | cpuid(0x80000001, &eax, &ebx, &ecx, &edx); | |
0f3fa48a | 1061 | |
39c06df4 BP |
1062 | c->x86_capability[CPUID_8000_0001_ECX] = ecx; |
1063 | c->x86_capability[CPUID_8000_0001_EDX] = edx; | |
093af8d7 | 1064 | } |
093af8d7 | 1065 | } |
093af8d7 | 1066 | |
71faad43 YG |
1067 | if (c->extended_cpuid_level >= 0x80000007) { |
1068 | cpuid(0x80000007, &eax, &ebx, &ecx, &edx); | |
1069 | ||
1070 | c->x86_capability[CPUID_8000_0007_EBX] = ebx; | |
1071 | c->x86_power = edx; | |
1072 | } | |
1073 | ||
c65732e4 TG |
1074 | if (c->extended_cpuid_level >= 0x80000008) { |
1075 | cpuid(0x80000008, &eax, &ebx, &ecx, &edx); | |
1076 | c->x86_capability[CPUID_8000_0008_EBX] = ebx; | |
1077 | } | |
1078 | ||
2ccd71f1 | 1079 | if (c->extended_cpuid_level >= 0x8000000a) |
39c06df4 | 1080 | c->x86_capability[CPUID_8000_000A_EDX] = cpuid_edx(0x8000000a); |
093af8d7 | 1081 | |
fb35d30f SC |
1082 | if (c->extended_cpuid_level >= 0x8000001f) |
1083 | c->x86_capability[CPUID_8000_001F_EAX] = cpuid_eax(0x8000001f); | |
1084 | ||
8415a748 KP |
1085 | if (c->extended_cpuid_level >= 0x80000021) |
1086 | c->x86_capability[CPUID_8000_0021_EAX] = cpuid_eax(0x80000021); | |
1087 | ||
1dedefd1 | 1088 | init_scattered_cpuid_features(c); |
7fcae111 | 1089 | init_speculation_control(c); |
60d34501 AL |
1090 | |
1091 | /* | |
1092 | * Clear/Set all flags overridden by options, after probe. | |
1093 | * This needs to happen each time we re-probe, which may happen | |
1094 | * several times during CPU initialization. | |
1095 | */ | |
1096 | apply_forced_caps(c); | |
093af8d7 | 1097 | } |
1da177e4 | 1098 | |
405c018a | 1099 | void get_cpu_address_sizes(struct cpuinfo_x86 *c) |
d94a155c KS |
1100 | { |
1101 | u32 eax, ebx, ecx, edx; | |
1102 | ||
1103 | if (c->extended_cpuid_level >= 0x80000008) { | |
1104 | cpuid(0x80000008, &eax, &ebx, &ecx, &edx); | |
1105 | ||
1106 | c->x86_virt_bits = (eax >> 8) & 0xff; | |
1107 | c->x86_phys_bits = eax & 0xff; | |
d94a155c KS |
1108 | } |
1109 | #ifdef CONFIG_X86_32 | |
1110 | else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36)) | |
1111 | c->x86_phys_bits = 36; | |
1112 | #endif | |
cc51e542 | 1113 | c->x86_cache_bits = c->x86_phys_bits; |
d94a155c KS |
1114 | } |
1115 | ||
148f9bb8 | 1116 | static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c) |
aef93c8b YL |
1117 | { |
1118 | #ifdef CONFIG_X86_32 | |
1119 | int i; | |
1120 | ||
1121 | /* | |
1122 | * First of all, decide if this is a 486 or higher | |
1123 | * It's a 486 if we can modify the AC flag | |
1124 | */ | |
1125 | if (flag_is_changeable_p(X86_EFLAGS_AC)) | |
1126 | c->x86 = 4; | |
1127 | else | |
1128 | c->x86 = 3; | |
1129 | ||
1130 | for (i = 0; i < X86_VENDOR_NUM; i++) | |
1131 | if (cpu_devs[i] && cpu_devs[i]->c_identify) { | |
1132 | c->x86_vendor_id[0] = 0; | |
1133 | cpu_devs[i]->c_identify(c); | |
1134 | if (c->x86_vendor_id[0]) { | |
1135 | get_cpu_vendor(c); | |
1136 | break; | |
1137 | } | |
1138 | } | |
1139 | #endif | |
1140 | } | |
1141 | ||
db4d30fb VT |
1142 | #define NO_SPECULATION BIT(0) |
1143 | #define NO_MELTDOWN BIT(1) | |
1144 | #define NO_SSB BIT(2) | |
1145 | #define NO_L1TF BIT(3) | |
1146 | #define NO_MDS BIT(4) | |
1147 | #define MSBDS_ONLY BIT(5) | |
1148 | #define NO_SWAPGS BIT(6) | |
1149 | #define NO_ITLB_MULTIHIT BIT(7) | |
1e41a766 | 1150 | #define NO_SPECTRE_V2 BIT(8) |
7df54884 PG |
1151 | #define NO_MMIO BIT(9) |
1152 | #define NO_EIBRS_PBRSB BIT(10) | |
36ad3513 | 1153 | |
f6d502fc TG |
1154 | #define VULNWL(vendor, family, model, whitelist) \ |
1155 | X86_MATCH_VENDOR_FAM_MODEL(vendor, family, model, whitelist) | |
36ad3513 TG |
1156 | |
1157 | #define VULNWL_INTEL(model, whitelist) \ | |
1158 | VULNWL(INTEL, 6, INTEL_FAM6_##model, whitelist) | |
1159 | ||
1160 | #define VULNWL_AMD(family, whitelist) \ | |
1161 | VULNWL(AMD, family, X86_MODEL_ANY, whitelist) | |
1162 | ||
1163 | #define VULNWL_HYGON(family, whitelist) \ | |
1164 | VULNWL(HYGON, family, X86_MODEL_ANY, whitelist) | |
1165 | ||
1166 | static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = { | |
1167 | VULNWL(ANY, 4, X86_MODEL_ANY, NO_SPECULATION), | |
1168 | VULNWL(CENTAUR, 5, X86_MODEL_ANY, NO_SPECULATION), | |
1169 | VULNWL(INTEL, 5, X86_MODEL_ANY, NO_SPECULATION), | |
1170 | VULNWL(NSC, 5, X86_MODEL_ANY, NO_SPECULATION), | |
639475d4 MDSV |
1171 | VULNWL(VORTEX, 5, X86_MODEL_ANY, NO_SPECULATION), |
1172 | VULNWL(VORTEX, 6, X86_MODEL_ANY, NO_SPECULATION), | |
36ad3513 | 1173 | |
ed5194c2 | 1174 | /* Intel Family 6 */ |
7df54884 PG |
1175 | VULNWL_INTEL(TIGERLAKE, NO_MMIO), |
1176 | VULNWL_INTEL(TIGERLAKE_L, NO_MMIO), | |
1177 | VULNWL_INTEL(ALDERLAKE, NO_MMIO), | |
1178 | VULNWL_INTEL(ALDERLAKE_L, NO_MMIO), | |
1179 | ||
db4d30fb VT |
1180 | VULNWL_INTEL(ATOM_SALTWELL, NO_SPECULATION | NO_ITLB_MULTIHIT), |
1181 | VULNWL_INTEL(ATOM_SALTWELL_TABLET, NO_SPECULATION | NO_ITLB_MULTIHIT), | |
1182 | VULNWL_INTEL(ATOM_SALTWELL_MID, NO_SPECULATION | NO_ITLB_MULTIHIT), | |
1183 | VULNWL_INTEL(ATOM_BONNELL, NO_SPECULATION | NO_ITLB_MULTIHIT), | |
1184 | VULNWL_INTEL(ATOM_BONNELL_MID, NO_SPECULATION | NO_ITLB_MULTIHIT), | |
1185 | ||
1186 | VULNWL_INTEL(ATOM_SILVERMONT, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT), | |
1187 | VULNWL_INTEL(ATOM_SILVERMONT_D, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT), | |
1188 | VULNWL_INTEL(ATOM_SILVERMONT_MID, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT), | |
1189 | VULNWL_INTEL(ATOM_AIRMONT, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT), | |
1190 | VULNWL_INTEL(XEON_PHI_KNL, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT), | |
1191 | VULNWL_INTEL(XEON_PHI_KNM, NO_SSB | NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT), | |
36ad3513 TG |
1192 | |
1193 | VULNWL_INTEL(CORE_YONAH, NO_SSB), | |
1194 | ||
db4d30fb VT |
1195 | VULNWL_INTEL(ATOM_AIRMONT_MID, NO_L1TF | MSBDS_ONLY | NO_SWAPGS | NO_ITLB_MULTIHIT), |
1196 | VULNWL_INTEL(ATOM_AIRMONT_NP, NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT), | |
36ad3513 | 1197 | |
7df54884 PG |
1198 | VULNWL_INTEL(ATOM_GOLDMONT, NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO), |
1199 | VULNWL_INTEL(ATOM_GOLDMONT_D, NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO), | |
1200 | VULNWL_INTEL(ATOM_GOLDMONT_PLUS, NO_MDS | NO_L1TF | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB), | |
f36cf386 TG |
1201 | |
1202 | /* | |
1203 | * Technically, swapgs isn't serializing on AMD (despite it previously | |
1204 | * being documented as such in the APM). But according to AMD, %gs is | |
1205 | * updated non-speculatively, and the issuing of %gs-relative memory | |
1206 | * operands will be blocked until the %gs update completes, which is | |
1207 | * good enough for our purposes. | |
1208 | */ | |
ed5194c2 | 1209 | |
2b129932 DS |
1210 | VULNWL_INTEL(ATOM_TREMONT, NO_EIBRS_PBRSB), |
1211 | VULNWL_INTEL(ATOM_TREMONT_L, NO_EIBRS_PBRSB), | |
1212 | VULNWL_INTEL(ATOM_TREMONT_D, NO_ITLB_MULTIHIT | NO_EIBRS_PBRSB), | |
cad14885 | 1213 | |
ed5194c2 | 1214 | /* AMD Family 0xf - 0x12 */ |
7df54884 PG |
1215 | VULNWL_AMD(0x0f, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO), |
1216 | VULNWL_AMD(0x10, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO), | |
1217 | VULNWL_AMD(0x11, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO), | |
1218 | VULNWL_AMD(0x12, NO_MELTDOWN | NO_SSB | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO), | |
36ad3513 TG |
1219 | |
1220 | /* FAMILY_ANY must be last, otherwise 0x0f - 0x12 matches won't work */ | |
e7862eda KP |
1221 | VULNWL_AMD(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB), |
1222 | VULNWL_HYGON(X86_FAMILY_ANY, NO_MELTDOWN | NO_L1TF | NO_MDS | NO_SWAPGS | NO_ITLB_MULTIHIT | NO_MMIO | NO_EIBRS_PBRSB), | |
1e41a766 TW |
1223 | |
1224 | /* Zhaoxin Family 7 */ | |
7df54884 PG |
1225 | VULNWL(CENTAUR, 7, X86_MODEL_ANY, NO_SPECTRE_V2 | NO_SWAPGS | NO_MMIO), |
1226 | VULNWL(ZHAOXIN, 7, X86_MODEL_ANY, NO_SPECTRE_V2 | NO_SWAPGS | NO_MMIO), | |
fec9434a DW |
1227 | {} |
1228 | }; | |
1229 | ||
6b80b59b AC |
1230 | #define VULNBL(vendor, family, model, blacklist) \ |
1231 | X86_MATCH_VENDOR_FAM_MODEL(vendor, family, model, blacklist) | |
1232 | ||
7e5b3c26 MG |
1233 | #define VULNBL_INTEL_STEPPINGS(model, steppings, issues) \ |
1234 | X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(INTEL, 6, \ | |
1235 | INTEL_FAM6_##model, steppings, \ | |
1236 | X86_FEATURE_ANY, issues) | |
1237 | ||
6b80b59b AC |
1238 | #define VULNBL_AMD(family, blacklist) \ |
1239 | VULNBL(AMD, family, X86_MODEL_ANY, blacklist) | |
1240 | ||
1241 | #define VULNBL_HYGON(family, blacklist) \ | |
1242 | VULNBL(HYGON, family, X86_MODEL_ANY, blacklist) | |
1243 | ||
7e5b3c26 | 1244 | #define SRBDS BIT(0) |
51802186 PG |
1245 | /* CPU is affected by X86_BUG_MMIO_STALE_DATA */ |
1246 | #define MMIO BIT(1) | |
a992b8a4 PG |
1247 | /* CPU is affected by Shared Buffers Data Sampling (SBDS), a variant of X86_BUG_MMIO_STALE_DATA */ |
1248 | #define MMIO_SBDS BIT(2) | |
6b80b59b AC |
1249 | /* CPU is affected by RETbleed, speculating where you would not expect it */ |
1250 | #define RETBLEED BIT(3) | |
be8de49b TL |
1251 | /* CPU is affected by SMT (cross-thread) return predictions */ |
1252 | #define SMT_RSB BIT(4) | |
7e5b3c26 MG |
1253 | |
1254 | static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = { | |
1255 | VULNBL_INTEL_STEPPINGS(IVYBRIDGE, X86_STEPPING_ANY, SRBDS), | |
1256 | VULNBL_INTEL_STEPPINGS(HASWELL, X86_STEPPING_ANY, SRBDS), | |
1257 | VULNBL_INTEL_STEPPINGS(HASWELL_L, X86_STEPPING_ANY, SRBDS), | |
1258 | VULNBL_INTEL_STEPPINGS(HASWELL_G, X86_STEPPING_ANY, SRBDS), | |
7a05bc95 PZ |
1259 | VULNBL_INTEL_STEPPINGS(HASWELL_X, X86_STEPPING_ANY, MMIO), |
1260 | VULNBL_INTEL_STEPPINGS(BROADWELL_D, X86_STEPPING_ANY, MMIO), | |
7e5b3c26 | 1261 | VULNBL_INTEL_STEPPINGS(BROADWELL_G, X86_STEPPING_ANY, SRBDS), |
51802186 | 1262 | VULNBL_INTEL_STEPPINGS(BROADWELL_X, X86_STEPPING_ANY, MMIO), |
7e5b3c26 | 1263 | VULNBL_INTEL_STEPPINGS(BROADWELL, X86_STEPPING_ANY, SRBDS), |
7a05bc95 PZ |
1264 | VULNBL_INTEL_STEPPINGS(SKYLAKE_L, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED), |
1265 | VULNBL_INTEL_STEPPINGS(SKYLAKE_X, X86_STEPPING_ANY, MMIO | RETBLEED), | |
1266 | VULNBL_INTEL_STEPPINGS(SKYLAKE, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED), | |
1267 | VULNBL_INTEL_STEPPINGS(KABYLAKE_L, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED), | |
1268 | VULNBL_INTEL_STEPPINGS(KABYLAKE, X86_STEPPING_ANY, SRBDS | MMIO | RETBLEED), | |
f54d4537 | 1269 | VULNBL_INTEL_STEPPINGS(CANNONLAKE_L, X86_STEPPING_ANY, RETBLEED), |
7a05bc95 PZ |
1270 | VULNBL_INTEL_STEPPINGS(ICELAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED), |
1271 | VULNBL_INTEL_STEPPINGS(ICELAKE_D, X86_STEPPING_ANY, MMIO), | |
1272 | VULNBL_INTEL_STEPPINGS(ICELAKE_X, X86_STEPPING_ANY, MMIO), | |
1273 | VULNBL_INTEL_STEPPINGS(COMETLAKE, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED), | |
6ad0ad2b | 1274 | VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO | RETBLEED), |
7a05bc95 PZ |
1275 | VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED), |
1276 | VULNBL_INTEL_STEPPINGS(LAKEFIELD, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED), | |
1277 | VULNBL_INTEL_STEPPINGS(ROCKETLAKE, X86_STEPPING_ANY, MMIO | RETBLEED), | |
1278 | VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPING_ANY, MMIO | MMIO_SBDS), | |
51802186 | 1279 | VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D, X86_STEPPING_ANY, MMIO), |
7a05bc95 | 1280 | VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS), |
6b80b59b AC |
1281 | |
1282 | VULNBL_AMD(0x15, RETBLEED), | |
1283 | VULNBL_AMD(0x16, RETBLEED), | |
be8de49b TL |
1284 | VULNBL_AMD(0x17, RETBLEED | SMT_RSB), |
1285 | VULNBL_HYGON(0x18, RETBLEED | SMT_RSB), | |
7e5b3c26 MG |
1286 | {} |
1287 | }; | |
1288 | ||
93920f61 | 1289 | static bool __init cpu_matches(const struct x86_cpu_id *table, unsigned long which) |
36ad3513 | 1290 | { |
93920f61 | 1291 | const struct x86_cpu_id *m = x86_match_cpu(table); |
c456442c | 1292 | |
36ad3513 TG |
1293 | return m && !!(m->driver_data & which); |
1294 | } | |
17dbca11 | 1295 | |
286836a7 | 1296 | u64 x86_read_arch_cap_msr(void) |
fec9434a DW |
1297 | { |
1298 | u64 ia32_cap = 0; | |
1299 | ||
286836a7 PG |
1300 | if (boot_cpu_has(X86_FEATURE_ARCH_CAPABILITIES)) |
1301 | rdmsrl(MSR_IA32_ARCH_CAPABILITIES, ia32_cap); | |
1302 | ||
1303 | return ia32_cap; | |
1304 | } | |
1305 | ||
51802186 PG |
1306 | static bool arch_cap_mmio_immune(u64 ia32_cap) |
1307 | { | |
1308 | return (ia32_cap & ARCH_CAP_FBSDP_NO && | |
1309 | ia32_cap & ARCH_CAP_PSDP_NO && | |
1310 | ia32_cap & ARCH_CAP_SBDR_SSDP_NO); | |
1311 | } | |
1312 | ||
286836a7 PG |
1313 | static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c) |
1314 | { | |
1315 | u64 ia32_cap = x86_read_arch_cap_msr(); | |
1316 | ||
db4d30fb | 1317 | /* Set ITLB_MULTIHIT bug if cpu is not in the whitelist and not mitigated */ |
93920f61 MG |
1318 | if (!cpu_matches(cpu_vuln_whitelist, NO_ITLB_MULTIHIT) && |
1319 | !(ia32_cap & ARCH_CAP_PSCHANGE_MC_NO)) | |
db4d30fb VT |
1320 | setup_force_cpu_bug(X86_BUG_ITLB_MULTIHIT); |
1321 | ||
93920f61 | 1322 | if (cpu_matches(cpu_vuln_whitelist, NO_SPECULATION)) |
8ecc4979 DB |
1323 | return; |
1324 | ||
1325 | setup_force_cpu_bug(X86_BUG_SPECTRE_V1); | |
1e41a766 | 1326 | |
93920f61 | 1327 | if (!cpu_matches(cpu_vuln_whitelist, NO_SPECTRE_V2)) |
1e41a766 | 1328 | setup_force_cpu_bug(X86_BUG_SPECTRE_V2); |
8ecc4979 | 1329 | |
93920f61 MG |
1330 | if (!cpu_matches(cpu_vuln_whitelist, NO_SSB) && |
1331 | !(ia32_cap & ARCH_CAP_SSB_NO) && | |
24809860 | 1332 | !cpu_has(c, X86_FEATURE_AMD_SSB_NO)) |
c456442c KRW |
1333 | setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS); |
1334 | ||
e7862eda KP |
1335 | /* |
1336 | * AMD's AutoIBRS is equivalent to Intel's eIBRS - use the Intel feature | |
1337 | * flag and protect from vendor-specific bugs via the whitelist. | |
1338 | */ | |
1339 | if ((ia32_cap & ARCH_CAP_IBRS_ALL) || cpu_has(c, X86_FEATURE_AUTOIBRS)) { | |
706d5168 | 1340 | setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED); |
e7862eda KP |
1341 | if (!cpu_matches(cpu_vuln_whitelist, NO_EIBRS_PBRSB) && |
1342 | !(ia32_cap & ARCH_CAP_PBRSB_NO)) | |
1343 | setup_force_cpu_bug(X86_BUG_EIBRS_PBRSB); | |
1344 | } | |
706d5168 | 1345 | |
93920f61 MG |
1346 | if (!cpu_matches(cpu_vuln_whitelist, NO_MDS) && |
1347 | !(ia32_cap & ARCH_CAP_MDS_NO)) { | |
ed5194c2 | 1348 | setup_force_cpu_bug(X86_BUG_MDS); |
93920f61 | 1349 | if (cpu_matches(cpu_vuln_whitelist, MSBDS_ONLY)) |
e261f209 TG |
1350 | setup_force_cpu_bug(X86_BUG_MSBDS_ONLY); |
1351 | } | |
ed5194c2 | 1352 | |
93920f61 | 1353 | if (!cpu_matches(cpu_vuln_whitelist, NO_SWAPGS)) |
f36cf386 TG |
1354 | setup_force_cpu_bug(X86_BUG_SWAPGS); |
1355 | ||
1b42f017 PG |
1356 | /* |
1357 | * When the CPU is not mitigated for TAA (TAA_NO=0) set TAA bug when: | |
1358 | * - TSX is supported or | |
1359 | * - TSX_CTRL is present | |
1360 | * | |
1361 | * TSX_CTRL check is needed for cases when TSX could be disabled before | |
1362 | * the kernel boot e.g. kexec. | |
1363 | * TSX_CTRL check alone is not sufficient for cases when the microcode | |
1364 | * update is not present or running as guest that don't get TSX_CTRL. | |
1365 | */ | |
1366 | if (!(ia32_cap & ARCH_CAP_TAA_NO) && | |
1367 | (cpu_has(c, X86_FEATURE_RTM) || | |
1368 | (ia32_cap & ARCH_CAP_TSX_CTRL_MSR))) | |
1369 | setup_force_cpu_bug(X86_BUG_TAA); | |
1370 | ||
7e5b3c26 MG |
1371 | /* |
1372 | * SRBDS affects CPUs which support RDRAND or RDSEED and are listed | |
1373 | * in the vulnerability blacklist. | |
a992b8a4 PG |
1374 | * |
1375 | * Some of the implications and mitigation of Shared Buffers Data | |
1376 | * Sampling (SBDS) are similar to SRBDS. Give SBDS same treatment as | |
1377 | * SRBDS. | |
7e5b3c26 MG |
1378 | */ |
1379 | if ((cpu_has(c, X86_FEATURE_RDRAND) || | |
1380 | cpu_has(c, X86_FEATURE_RDSEED)) && | |
a992b8a4 | 1381 | cpu_matches(cpu_vuln_blacklist, SRBDS | MMIO_SBDS)) |
7e5b3c26 MG |
1382 | setup_force_cpu_bug(X86_BUG_SRBDS); |
1383 | ||
51802186 PG |
1384 | /* |
1385 | * Processor MMIO Stale Data bug enumeration | |
1386 | * | |
1387 | * Affected CPU list is generally enough to enumerate the vulnerability, | |
1388 | * but for virtualization case check for ARCH_CAP MSR bits also, VMM may | |
1389 | * not want the guest to enumerate the bug. | |
7df54884 PG |
1390 | * |
1391 | * Set X86_BUG_MMIO_UNKNOWN for CPUs that are neither in the blacklist, | |
1392 | * nor in the whitelist and also don't enumerate MSR ARCH_CAP MMIO bits. | |
51802186 | 1393 | */ |
7df54884 PG |
1394 | if (!arch_cap_mmio_immune(ia32_cap)) { |
1395 | if (cpu_matches(cpu_vuln_blacklist, MMIO)) | |
1396 | setup_force_cpu_bug(X86_BUG_MMIO_STALE_DATA); | |
1397 | else if (!cpu_matches(cpu_vuln_whitelist, NO_MMIO)) | |
1398 | setup_force_cpu_bug(X86_BUG_MMIO_UNKNOWN); | |
1399 | } | |
51802186 | 1400 | |
26aae8cc AC |
1401 | if (!cpu_has(c, X86_FEATURE_BTC_NO)) { |
1402 | if (cpu_matches(cpu_vuln_blacklist, RETBLEED) || (ia32_cap & ARCH_CAP_RSBA)) | |
1403 | setup_force_cpu_bug(X86_BUG_RETBLEED); | |
1404 | } | |
6b80b59b | 1405 | |
be8de49b TL |
1406 | if (cpu_matches(cpu_vuln_blacklist, SMT_RSB)) |
1407 | setup_force_cpu_bug(X86_BUG_SMT_RSB); | |
1408 | ||
93920f61 | 1409 | if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN)) |
4a28bfe3 | 1410 | return; |
fec9434a | 1411 | |
fec9434a DW |
1412 | /* Rogue Data Cache Load? No! */ |
1413 | if (ia32_cap & ARCH_CAP_RDCL_NO) | |
4a28bfe3 | 1414 | return; |
fec9434a | 1415 | |
4a28bfe3 | 1416 | setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN); |
17dbca11 | 1417 | |
93920f61 | 1418 | if (cpu_matches(cpu_vuln_whitelist, NO_L1TF)) |
17dbca11 AK |
1419 | return; |
1420 | ||
1421 | setup_force_cpu_bug(X86_BUG_L1TF); | |
fec9434a DW |
1422 | } |
1423 | ||
8990cac6 PT |
1424 | /* |
1425 | * The NOPL instruction is supposed to exist on all CPUs of family >= 6; | |
1426 | * unfortunately, that's not true in practice because of early VIA | |
1427 | * chips and (more importantly) broken virtualizers that are not easy | |
1428 | * to detect. In the latter case it doesn't even *fail* reliably, so | |
1429 | * probing for it doesn't even work. Disable it completely on 32-bit | |
1430 | * unless we can find a reliable way to detect all the broken cases. | |
1431 | * Enable it explicitly on 64-bit for non-constant inputs of cpu_has(). | |
1432 | */ | |
9b3661cd | 1433 | static void detect_nopl(void) |
8990cac6 PT |
1434 | { |
1435 | #ifdef CONFIG_X86_32 | |
9b3661cd | 1436 | setup_clear_cpu_cap(X86_FEATURE_NOPL); |
8990cac6 | 1437 | #else |
9b3661cd | 1438 | setup_force_cpu_cap(X86_FEATURE_NOPL); |
8990cac6 PT |
1439 | #endif |
1440 | } | |
1441 | ||
1ef5423a MH |
1442 | /* |
1443 | * We parse cpu parameters early because fpu__init_system() is executed | |
1444 | * before parse_early_param(). | |
1445 | */ | |
1446 | static void __init cpu_parse_early_param(void) | |
1447 | { | |
1448 | char arg[128]; | |
1625c833 BP |
1449 | char *argptr = arg, *opt; |
1450 | int arglen, taint = 0; | |
1ef5423a MH |
1451 | |
1452 | #ifdef CONFIG_X86_32 | |
1453 | if (cmdline_find_option_bool(boot_command_line, "no387")) | |
1454 | #ifdef CONFIG_MATH_EMULATION | |
1455 | setup_clear_cpu_cap(X86_FEATURE_FPU); | |
1456 | #else | |
1457 | pr_err("Option 'no387' required CONFIG_MATH_EMULATION enabled.\n"); | |
1458 | #endif | |
1459 | ||
1460 | if (cmdline_find_option_bool(boot_command_line, "nofxsr")) | |
1461 | setup_clear_cpu_cap(X86_FEATURE_FXSR); | |
1462 | #endif | |
1463 | ||
1464 | if (cmdline_find_option_bool(boot_command_line, "noxsave")) | |
1465 | setup_clear_cpu_cap(X86_FEATURE_XSAVE); | |
1466 | ||
1467 | if (cmdline_find_option_bool(boot_command_line, "noxsaveopt")) | |
1468 | setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); | |
1469 | ||
1470 | if (cmdline_find_option_bool(boot_command_line, "noxsaves")) | |
1471 | setup_clear_cpu_cap(X86_FEATURE_XSAVES); | |
1472 | ||
1473 | arglen = cmdline_find_option(boot_command_line, "clearcpuid", arg, sizeof(arg)); | |
1474 | if (arglen <= 0) | |
1475 | return; | |
1476 | ||
1477 | pr_info("Clearing CPUID bits:"); | |
1ef5423a | 1478 | |
1625c833 BP |
1479 | while (argptr) { |
1480 | bool found __maybe_unused = false; | |
1481 | unsigned int bit; | |
1ef5423a | 1482 | |
1625c833 BP |
1483 | opt = strsep(&argptr, ","); |
1484 | ||
1485 | /* | |
1486 | * Handle naked numbers first for feature flags which don't | |
1487 | * have names. | |
1488 | */ | |
1489 | if (!kstrtouint(opt, 10, &bit)) { | |
1490 | if (bit < NCAPINTS * 32) { | |
1491 | ||
1625c833 BP |
1492 | /* empty-string, i.e., ""-defined feature flags */ |
1493 | if (!x86_cap_flags[bit]) | |
1494 | pr_cont(" " X86_CAP_FMT_NUM, x86_cap_flag_num(bit)); | |
1495 | else | |
1625c833 BP |
1496 | pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit)); |
1497 | ||
1498 | setup_clear_cpu_cap(bit); | |
1499 | taint++; | |
1500 | } | |
1501 | /* | |
1502 | * The assumption is that there are no feature names with only | |
1503 | * numbers in the name thus go to the next argument. | |
1504 | */ | |
1505 | continue; | |
1506 | } | |
1507 | ||
1625c833 BP |
1508 | for (bit = 0; bit < 32 * NCAPINTS; bit++) { |
1509 | if (!x86_cap_flag(bit)) | |
1510 | continue; | |
1ef5423a | 1511 | |
1625c833 BP |
1512 | if (strcmp(x86_cap_flag(bit), opt)) |
1513 | continue; | |
1514 | ||
1515 | pr_cont(" %s", opt); | |
1ef5423a | 1516 | setup_clear_cpu_cap(bit); |
1625c833 BP |
1517 | taint++; |
1518 | found = true; | |
1519 | break; | |
1ef5423a | 1520 | } |
1625c833 BP |
1521 | |
1522 | if (!found) | |
1523 | pr_cont(" (unknown: %s)", opt); | |
1625c833 | 1524 | } |
1ef5423a | 1525 | pr_cont("\n"); |
1625c833 BP |
1526 | |
1527 | if (taint) | |
1528 | add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK); | |
1ef5423a MH |
1529 | } |
1530 | ||
34048c9e PC |
1531 | /* |
1532 | * Do minimum CPU detection early. | |
1533 | * Fields really needed: vendor, cpuid_level, family, model, mask, | |
1534 | * cache alignment. | |
1535 | * The others are not touched to avoid unwanted side effects. | |
1536 | * | |
a1652bb8 JD |
1537 | * WARNING: this function is only called on the boot CPU. Don't add code |
1538 | * here that is supposed to run on all CPUs. | |
34048c9e | 1539 | */ |
3da99c97 | 1540 | static void __init early_identify_cpu(struct cpuinfo_x86 *c) |
d7cd5611 | 1541 | { |
6627d242 YL |
1542 | #ifdef CONFIG_X86_64 |
1543 | c->x86_clflush_size = 64; | |
13c6c532 JB |
1544 | c->x86_phys_bits = 36; |
1545 | c->x86_virt_bits = 48; | |
6627d242 | 1546 | #else |
d4387bd3 | 1547 | c->x86_clflush_size = 32; |
13c6c532 JB |
1548 | c->x86_phys_bits = 32; |
1549 | c->x86_virt_bits = 32; | |
6627d242 | 1550 | #endif |
0a488a53 | 1551 | c->x86_cache_alignment = c->x86_clflush_size; |
d7cd5611 | 1552 | |
0e96f31e | 1553 | memset(&c->x86_capability, 0, sizeof(c->x86_capability)); |
0a488a53 | 1554 | c->extended_cpuid_level = 0; |
d7cd5611 | 1555 | |
2893cc8f MW |
1556 | if (!have_cpuid_p()) |
1557 | identify_cpu_without_cpuid(c); | |
1558 | ||
aef93c8b | 1559 | /* cyrix could have cpuid enabled via c_identify()*/ |
05fb3c19 AL |
1560 | if (have_cpuid_p()) { |
1561 | cpu_detect(c); | |
1562 | get_cpu_vendor(c); | |
1563 | get_cpu_cap(c); | |
d94a155c | 1564 | get_cpu_address_sizes(c); |
78d1b296 | 1565 | setup_force_cpu_cap(X86_FEATURE_CPUID); |
1ef5423a | 1566 | cpu_parse_early_param(); |
d7cd5611 | 1567 | |
05fb3c19 AL |
1568 | if (this_cpu->c_early_init) |
1569 | this_cpu->c_early_init(c); | |
12cf105c | 1570 | |
05fb3c19 AL |
1571 | c->cpu_index = 0; |
1572 | filter_cpuid_features(c, false); | |
093af8d7 | 1573 | |
05fb3c19 AL |
1574 | if (this_cpu->c_bsp_init) |
1575 | this_cpu->c_bsp_init(c); | |
78d1b296 | 1576 | } else { |
78d1b296 | 1577 | setup_clear_cpu_cap(X86_FEATURE_CPUID); |
05fb3c19 | 1578 | } |
c3b83598 BP |
1579 | |
1580 | setup_force_cpu_cap(X86_FEATURE_ALWAYS); | |
a89f040f | 1581 | |
4a28bfe3 | 1582 | cpu_set_bug_bits(c); |
99c6fa25 | 1583 | |
ebb1064e | 1584 | sld_setup(c); |
6650cdd9 | 1585 | |
b8b7abae AL |
1586 | #ifdef CONFIG_X86_32 |
1587 | /* | |
1588 | * Regardless of whether PCID is enumerated, the SDM says | |
1589 | * that it can't be enabled in 32-bit mode. | |
1590 | */ | |
1591 | setup_clear_cpu_cap(X86_FEATURE_PCID); | |
1592 | #endif | |
372fddf7 KS |
1593 | |
1594 | /* | |
1595 | * Later in the boot process pgtable_l5_enabled() relies on | |
1596 | * cpu_feature_enabled(X86_FEATURE_LA57). If 5-level paging is not | |
1597 | * enabled by this point we need to clear the feature bit to avoid | |
1598 | * false-positives at the later stage. | |
1599 | * | |
1600 | * pgtable_l5_enabled() can be false here for several reasons: | |
1601 | * - 5-level paging is disabled compile-time; | |
1602 | * - it's 32-bit kernel; | |
1603 | * - machine doesn't support 5-level paging; | |
1604 | * - user specified 'no5lvl' in kernel command line. | |
1605 | */ | |
1606 | if (!pgtable_l5_enabled()) | |
1607 | setup_clear_cpu_cap(X86_FEATURE_LA57); | |
8990cac6 | 1608 | |
9b3661cd | 1609 | detect_nopl(); |
d7cd5611 RR |
1610 | } |
1611 | ||
9d31d35b YL |
1612 | void __init early_cpu_init(void) |
1613 | { | |
02dde8b4 | 1614 | const struct cpu_dev *const *cdev; |
10a434fc YL |
1615 | int count = 0; |
1616 | ||
ac23f253 | 1617 | #ifdef CONFIG_PROCESSOR_SELECT |
1b74dde7 | 1618 | pr_info("KERNEL supported cpus:\n"); |
31c997ca IM |
1619 | #endif |
1620 | ||
10a434fc | 1621 | for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) { |
02dde8b4 | 1622 | const struct cpu_dev *cpudev = *cdev; |
9d31d35b | 1623 | |
10a434fc YL |
1624 | if (count >= X86_VENDOR_NUM) |
1625 | break; | |
1626 | cpu_devs[count] = cpudev; | |
1627 | count++; | |
1628 | ||
ac23f253 | 1629 | #ifdef CONFIG_PROCESSOR_SELECT |
31c997ca IM |
1630 | { |
1631 | unsigned int j; | |
1632 | ||
1633 | for (j = 0; j < 2; j++) { | |
1634 | if (!cpudev->c_ident[j]) | |
1635 | continue; | |
1b74dde7 | 1636 | pr_info(" %s %s\n", cpudev->c_vendor, |
31c997ca IM |
1637 | cpudev->c_ident[j]); |
1638 | } | |
10a434fc | 1639 | } |
0388423d | 1640 | #endif |
10a434fc | 1641 | } |
9d31d35b | 1642 | early_identify_cpu(&boot_cpu_data); |
d7cd5611 | 1643 | } |
093af8d7 | 1644 | |
415de440 | 1645 | static bool detect_null_seg_behavior(void) |
7a5d6704 | 1646 | { |
58a5aac5 | 1647 | /* |
7a5d6704 AL |
1648 | * Empirically, writing zero to a segment selector on AMD does |
1649 | * not clear the base, whereas writing zero to a segment | |
1650 | * selector on Intel does clear the base. Intel's behavior | |
1651 | * allows slightly faster context switches in the common case | |
1652 | * where GS is unused by the prev and next threads. | |
58a5aac5 | 1653 | * |
7a5d6704 | 1654 | * Since neither vendor documents this anywhere that I can see, |
d9f6e12f | 1655 | * detect it directly instead of hard-coding the choice by |
7a5d6704 AL |
1656 | * vendor. |
1657 | * | |
1658 | * I've designated AMD's behavior as the "bug" because it's | |
1659 | * counterintuitive and less friendly. | |
58a5aac5 | 1660 | */ |
7a5d6704 AL |
1661 | |
1662 | unsigned long old_base, tmp; | |
1663 | rdmsrl(MSR_FS_BASE, old_base); | |
1664 | wrmsrl(MSR_FS_BASE, 1); | |
1665 | loadsegment(fs, 0); | |
1666 | rdmsrl(MSR_FS_BASE, tmp); | |
7a5d6704 | 1667 | wrmsrl(MSR_FS_BASE, old_base); |
415de440 JM |
1668 | return tmp == 0; |
1669 | } | |
1670 | ||
1671 | void check_null_seg_clears_base(struct cpuinfo_x86 *c) | |
1672 | { | |
1673 | /* BUG_NULL_SEG is only relevant with 64bit userspace */ | |
1674 | if (!IS_ENABLED(CONFIG_X86_64)) | |
1675 | return; | |
1676 | ||
5b909d4a | 1677 | if (cpu_has(c, X86_FEATURE_NULL_SEL_CLR_BASE)) |
415de440 JM |
1678 | return; |
1679 | ||
1680 | /* | |
1681 | * CPUID bit above wasn't set. If this kernel is still running | |
1682 | * as a HV guest, then the HV has decided not to advertize | |
1683 | * that CPUID bit for whatever reason. For example, one | |
1684 | * member of the migration pool might be vulnerable. Which | |
1685 | * means, the bug is present: set the BUG flag and return. | |
1686 | */ | |
1687 | if (cpu_has(c, X86_FEATURE_HYPERVISOR)) { | |
1688 | set_cpu_bug(c, X86_BUG_NULL_SEG); | |
1689 | return; | |
1690 | } | |
1691 | ||
1692 | /* | |
1693 | * Zen2 CPUs also have this behaviour, but no CPUID bit. | |
1694 | * 0x18 is the respective family for Hygon. | |
1695 | */ | |
1696 | if ((c->x86 == 0x17 || c->x86 == 0x18) && | |
1697 | detect_null_seg_behavior()) | |
1698 | return; | |
1699 | ||
1700 | /* All the remaining ones are affected */ | |
1701 | set_cpu_bug(c, X86_BUG_NULL_SEG); | |
d7cd5611 RR |
1702 | } |
1703 | ||
148f9bb8 | 1704 | static void generic_identify(struct cpuinfo_x86 *c) |
1da177e4 | 1705 | { |
aef93c8b | 1706 | c->extended_cpuid_level = 0; |
1da177e4 | 1707 | |
3da99c97 | 1708 | if (!have_cpuid_p()) |
aef93c8b | 1709 | identify_cpu_without_cpuid(c); |
1d67953f | 1710 | |
aef93c8b | 1711 | /* cyrix could have cpuid enabled via c_identify()*/ |
a9853dd6 | 1712 | if (!have_cpuid_p()) |
aef93c8b | 1713 | return; |
1da177e4 | 1714 | |
3da99c97 | 1715 | cpu_detect(c); |
1da177e4 | 1716 | |
3da99c97 | 1717 | get_cpu_vendor(c); |
1da177e4 | 1718 | |
3da99c97 | 1719 | get_cpu_cap(c); |
1da177e4 | 1720 | |
d94a155c KS |
1721 | get_cpu_address_sizes(c); |
1722 | ||
3da99c97 YL |
1723 | if (c->cpuid_level >= 0x00000001) { |
1724 | c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF; | |
b89d3b3e | 1725 | #ifdef CONFIG_X86_32 |
c8e56d20 | 1726 | # ifdef CONFIG_SMP |
cb8cc442 | 1727 | c->apicid = apic->phys_pkg_id(c->initial_apicid, 0); |
b89d3b3e | 1728 | # else |
3da99c97 | 1729 | c->apicid = c->initial_apicid; |
b89d3b3e YL |
1730 | # endif |
1731 | #endif | |
b89d3b3e | 1732 | c->phys_proc_id = c->initial_apicid; |
3da99c97 | 1733 | } |
1da177e4 | 1734 | |
1b05d60d | 1735 | get_model_name(c); /* Default name */ |
1da177e4 | 1736 | |
0230bb03 AL |
1737 | /* |
1738 | * ESPFIX is a strange bug. All real CPUs have it. Paravirt | |
1739 | * systems that run Linux at CPL > 0 may or may not have the | |
1740 | * issue, but, even if they have the issue, there's absolutely | |
1741 | * nothing we can do about it because we can't use the real IRET | |
1742 | * instruction. | |
1743 | * | |
1744 | * NB: For the time being, only 32-bit kernels support | |
1745 | * X86_BUG_ESPFIX as such. 64-bit kernels directly choose | |
1746 | * whether to apply espfix using paravirt hooks. If any | |
1747 | * non-paravirt system ever shows up that does *not* have the | |
1748 | * ESPFIX issue, we can change this. | |
1749 | */ | |
1750 | #ifdef CONFIG_X86_32 | |
0230bb03 | 1751 | set_cpu_bug(c, X86_BUG_ESPFIX); |
0230bb03 | 1752 | #endif |
1da177e4 | 1753 | } |
1da177e4 | 1754 | |
d49597fd | 1755 | /* |
9d85eb91 TG |
1756 | * Validate that ACPI/mptables have the same information about the |
1757 | * effective APIC id and update the package map. | |
d49597fd | 1758 | */ |
9d85eb91 | 1759 | static void validate_apic_and_package_id(struct cpuinfo_x86 *c) |
d49597fd TG |
1760 | { |
1761 | #ifdef CONFIG_SMP | |
9d85eb91 | 1762 | unsigned int apicid, cpu = smp_processor_id(); |
d49597fd TG |
1763 | |
1764 | apicid = apic->cpu_present_to_apicid(cpu); | |
d49597fd | 1765 | |
9d85eb91 TG |
1766 | if (apicid != c->apicid) { |
1767 | pr_err(FW_BUG "CPU%u: APIC id mismatch. Firmware: %x APIC: %x\n", | |
d49597fd | 1768 | cpu, apicid, c->initial_apicid); |
d49597fd | 1769 | } |
9d85eb91 | 1770 | BUG_ON(topology_update_package_map(c->phys_proc_id, cpu)); |
212bf4fd | 1771 | BUG_ON(topology_update_die_map(c->cpu_die_id, cpu)); |
d49597fd TG |
1772 | #else |
1773 | c->logical_proc_id = 0; | |
1774 | #endif | |
1775 | } | |
1776 | ||
1da177e4 LT |
1777 | /* |
1778 | * This does the hard work of actually picking apart the CPU stuff... | |
1779 | */ | |
148f9bb8 | 1780 | static void identify_cpu(struct cpuinfo_x86 *c) |
1da177e4 LT |
1781 | { |
1782 | int i; | |
1783 | ||
1784 | c->loops_per_jiffy = loops_per_jiffy; | |
24dbc600 | 1785 | c->x86_cache_size = 0; |
1da177e4 | 1786 | c->x86_vendor = X86_VENDOR_UNKNOWN; |
b399151c | 1787 | c->x86_model = c->x86_stepping = 0; /* So far unknown... */ |
1da177e4 LT |
1788 | c->x86_vendor_id[0] = '\0'; /* Unset */ |
1789 | c->x86_model_id[0] = '\0'; /* Unset */ | |
94605eff | 1790 | c->x86_max_cores = 1; |
102bbe3a | 1791 | c->x86_coreid_bits = 0; |
79a8b9aa | 1792 | c->cu_id = 0xff; |
11fdd252 | 1793 | #ifdef CONFIG_X86_64 |
102bbe3a | 1794 | c->x86_clflush_size = 64; |
13c6c532 JB |
1795 | c->x86_phys_bits = 36; |
1796 | c->x86_virt_bits = 48; | |
102bbe3a YL |
1797 | #else |
1798 | c->cpuid_level = -1; /* CPUID not detected */ | |
770d132f | 1799 | c->x86_clflush_size = 32; |
13c6c532 JB |
1800 | c->x86_phys_bits = 32; |
1801 | c->x86_virt_bits = 32; | |
102bbe3a YL |
1802 | #endif |
1803 | c->x86_cache_alignment = c->x86_clflush_size; | |
0e96f31e | 1804 | memset(&c->x86_capability, 0, sizeof(c->x86_capability)); |
b47ce1fe SC |
1805 | #ifdef CONFIG_X86_VMX_FEATURE_NAMES |
1806 | memset(&c->vmx_capability, 0, sizeof(c->vmx_capability)); | |
1807 | #endif | |
1da177e4 | 1808 | |
1da177e4 LT |
1809 | generic_identify(c); |
1810 | ||
3898534d | 1811 | if (this_cpu->c_identify) |
1da177e4 LT |
1812 | this_cpu->c_identify(c); |
1813 | ||
6a6256f9 | 1814 | /* Clear/Set all flags overridden by options, after probe */ |
8bf1ebca | 1815 | apply_forced_caps(c); |
2759c328 | 1816 | |
102bbe3a | 1817 | #ifdef CONFIG_X86_64 |
cb8cc442 | 1818 | c->apicid = apic->phys_pkg_id(c->initial_apicid, 0); |
102bbe3a YL |
1819 | #endif |
1820 | ||
1da177e4 LT |
1821 | /* |
1822 | * Vendor-specific initialization. In this section we | |
1823 | * canonicalize the feature flags, meaning if there are | |
1824 | * features a certain CPU supports which CPUID doesn't | |
1825 | * tell us, CPUID claiming incorrect flags, or other bugs, | |
1826 | * we handle them here. | |
1827 | * | |
1828 | * At the end of this section, c->x86_capability better | |
1829 | * indicate the features this CPU genuinely supports! | |
1830 | */ | |
1831 | if (this_cpu->c_init) | |
1832 | this_cpu->c_init(c); | |
1833 | ||
1834 | /* Disable the PN if appropriate */ | |
1835 | squash_the_stupid_serial_number(c); | |
1836 | ||
aa35f896 | 1837 | /* Set up SMEP/SMAP/UMIP */ |
b2cc2a07 PA |
1838 | setup_smep(c); |
1839 | setup_smap(c); | |
aa35f896 | 1840 | setup_umip(c); |
b2cc2a07 | 1841 | |
dd649bd0 | 1842 | /* Enable FSGSBASE instructions if available. */ |
742c45c3 | 1843 | if (cpu_has(c, X86_FEATURE_FSGSBASE)) { |
b745cfba | 1844 | cr4_set_bits(X86_CR4_FSGSBASE); |
742c45c3 AK |
1845 | elf_hwcap2 |= HWCAP2_FSGSBASE; |
1846 | } | |
dd649bd0 | 1847 | |
1da177e4 | 1848 | /* |
0f3fa48a IM |
1849 | * The vendor-specific functions might have changed features. |
1850 | * Now we do "generic changes." | |
1da177e4 LT |
1851 | */ |
1852 | ||
b38b0665 PA |
1853 | /* Filter out anything that depends on CPUID levels we don't have */ |
1854 | filter_cpuid_features(c, true); | |
1855 | ||
1da177e4 | 1856 | /* If the model name is still unset, do table lookup. */ |
34048c9e | 1857 | if (!c->x86_model_id[0]) { |
02dde8b4 | 1858 | const char *p; |
1da177e4 | 1859 | p = table_lookup_model(c); |
34048c9e | 1860 | if (p) |
1da177e4 LT |
1861 | strcpy(c->x86_model_id, p); |
1862 | else | |
1863 | /* Last resort... */ | |
1864 | sprintf(c->x86_model_id, "%02x/%02x", | |
54a20f8c | 1865 | c->x86, c->x86_model); |
1da177e4 LT |
1866 | } |
1867 | ||
102bbe3a YL |
1868 | #ifdef CONFIG_X86_64 |
1869 | detect_ht(c); | |
1870 | #endif | |
1871 | ||
49d859d7 | 1872 | x86_init_rdrand(c); |
06976945 | 1873 | setup_pku(c); |
991625f3 | 1874 | setup_cet(c); |
3e0c3737 YL |
1875 | |
1876 | /* | |
6a6256f9 | 1877 | * Clear/Set all flags overridden by options, need do it |
3e0c3737 YL |
1878 | * before following smp all cpus cap AND. |
1879 | */ | |
8bf1ebca | 1880 | apply_forced_caps(c); |
3e0c3737 | 1881 | |
1da177e4 LT |
1882 | /* |
1883 | * On SMP, boot_cpu_data holds the common feature set between | |
1884 | * all CPUs; so make sure that we indicate which features are | |
1885 | * common between the CPUs. The first time this routine gets | |
1886 | * executed, c == &boot_cpu_data. | |
1887 | */ | |
34048c9e | 1888 | if (c != &boot_cpu_data) { |
1da177e4 | 1889 | /* AND the already accumulated flags with these */ |
9d31d35b | 1890 | for (i = 0; i < NCAPINTS; i++) |
1da177e4 | 1891 | boot_cpu_data.x86_capability[i] &= c->x86_capability[i]; |
65fc985b BP |
1892 | |
1893 | /* OR, i.e. replicate the bug flags */ | |
1894 | for (i = NCAPINTS; i < NCAPINTS + NBUGINTS; i++) | |
1895 | c->x86_capability[i] |= boot_cpu_data.x86_capability[i]; | |
1da177e4 LT |
1896 | } |
1897 | ||
0dcab41d TL |
1898 | ppin_init(c); |
1899 | ||
1da177e4 | 1900 | /* Init Machine Check Exception if available. */ |
5e09954a | 1901 | mcheck_cpu_init(c); |
30d432df AK |
1902 | |
1903 | select_idle_routine(c); | |
102bbe3a | 1904 | |
de2d9445 | 1905 | #ifdef CONFIG_NUMA |
102bbe3a YL |
1906 | numa_add_cpu(smp_processor_id()); |
1907 | #endif | |
a6c4e076 | 1908 | } |
31ab269a | 1909 | |
8b6c0ab1 IM |
1910 | /* |
1911 | * Set up the CPU state needed to execute SYSENTER/SYSEXIT instructions | |
1912 | * on 32-bit kernels: | |
1913 | */ | |
cfda7bb9 AL |
1914 | #ifdef CONFIG_X86_32 |
1915 | void enable_sep_cpu(void) | |
1916 | { | |
8b6c0ab1 IM |
1917 | struct tss_struct *tss; |
1918 | int cpu; | |
cfda7bb9 | 1919 | |
b3edfda4 BP |
1920 | if (!boot_cpu_has(X86_FEATURE_SEP)) |
1921 | return; | |
1922 | ||
8b6c0ab1 | 1923 | cpu = get_cpu(); |
c482feef | 1924 | tss = &per_cpu(cpu_tss_rw, cpu); |
8b6c0ab1 | 1925 | |
8b6c0ab1 | 1926 | /* |
cf9328cc AL |
1927 | * We cache MSR_IA32_SYSENTER_CS's value in the TSS's ss1 field -- |
1928 | * see the big comment in struct x86_hw_tss's definition. | |
8b6c0ab1 | 1929 | */ |
cfda7bb9 AL |
1930 | |
1931 | tss->x86_tss.ss1 = __KERNEL_CS; | |
8b6c0ab1 | 1932 | wrmsr(MSR_IA32_SYSENTER_CS, tss->x86_tss.ss1, 0); |
4fe2d8b1 | 1933 | wrmsr(MSR_IA32_SYSENTER_ESP, (unsigned long)(cpu_entry_stack(cpu) + 1), 0); |
4c8cd0c5 | 1934 | wrmsr(MSR_IA32_SYSENTER_EIP, (unsigned long)entry_SYSENTER_32, 0); |
8b6c0ab1 | 1935 | |
cfda7bb9 AL |
1936 | put_cpu(); |
1937 | } | |
e04d645f GC |
1938 | #endif |
1939 | ||
a6c4e076 JF |
1940 | void __init identify_boot_cpu(void) |
1941 | { | |
1942 | identify_cpu(&boot_cpu_data); | |
991625f3 PZ |
1943 | if (HAS_KERNEL_IBT && cpu_feature_enabled(X86_FEATURE_IBT)) |
1944 | pr_info("CET detected: Indirect Branch Tracking enabled\n"); | |
102bbe3a | 1945 | #ifdef CONFIG_X86_32 |
6fe940d6 | 1946 | enable_sep_cpu(); |
102bbe3a | 1947 | #endif |
5b556332 | 1948 | cpu_detect_tlb(&boot_cpu_data); |
873d50d5 | 1949 | setup_cr_pinning(); |
95c5824f PG |
1950 | |
1951 | tsx_init(); | |
92cbbadf | 1952 | lkgs_init(); |
a6c4e076 | 1953 | } |
3b520b23 | 1954 | |
148f9bb8 | 1955 | void identify_secondary_cpu(struct cpuinfo_x86 *c) |
a6c4e076 JF |
1956 | { |
1957 | BUG_ON(c == &boot_cpu_data); | |
1958 | identify_cpu(c); | |
102bbe3a | 1959 | #ifdef CONFIG_X86_32 |
a6c4e076 | 1960 | enable_sep_cpu(); |
102bbe3a | 1961 | #endif |
9d85eb91 | 1962 | validate_apic_and_package_id(c); |
77243971 | 1963 | x86_spec_ctrl_setup_ap(); |
7e5b3c26 | 1964 | update_srbds_msr(); |
400331f8 PG |
1965 | |
1966 | tsx_ap_init(); | |
1da177e4 LT |
1967 | } |
1968 | ||
148f9bb8 | 1969 | void print_cpu_info(struct cpuinfo_x86 *c) |
1da177e4 | 1970 | { |
02dde8b4 | 1971 | const char *vendor = NULL; |
1da177e4 | 1972 | |
0f3fa48a | 1973 | if (c->x86_vendor < X86_VENDOR_NUM) { |
1da177e4 | 1974 | vendor = this_cpu->c_vendor; |
0f3fa48a IM |
1975 | } else { |
1976 | if (c->cpuid_level >= 0) | |
1977 | vendor = c->x86_vendor_id; | |
1978 | } | |
1da177e4 | 1979 | |
bd32a8cf | 1980 | if (vendor && !strstr(c->x86_model_id, vendor)) |
1b74dde7 | 1981 | pr_cont("%s ", vendor); |
1da177e4 | 1982 | |
9d31d35b | 1983 | if (c->x86_model_id[0]) |
1b74dde7 | 1984 | pr_cont("%s", c->x86_model_id); |
1da177e4 | 1985 | else |
1b74dde7 | 1986 | pr_cont("%d86", c->x86); |
1da177e4 | 1987 | |
1b74dde7 | 1988 | pr_cont(" (family: 0x%x, model: 0x%x", c->x86, c->x86_model); |
924e101a | 1989 | |
b399151c JZ |
1990 | if (c->x86_stepping || c->cpuid_level >= 0) |
1991 | pr_cont(", stepping: 0x%x)\n", c->x86_stepping); | |
1da177e4 | 1992 | else |
1b74dde7 | 1993 | pr_cont(")\n"); |
1da177e4 LT |
1994 | } |
1995 | ||
0c2a3913 | 1996 | /* |
ce38f038 TG |
1997 | * clearcpuid= was already parsed in cpu_parse_early_param(). This dummy |
1998 | * function prevents it from becoming an environment variable for init. | |
0c2a3913 AK |
1999 | */ |
2000 | static __init int setup_clearcpuid(char *arg) | |
ac72e788 | 2001 | { |
ac72e788 AK |
2002 | return 1; |
2003 | } | |
0c2a3913 | 2004 | __setup("clearcpuid=", setup_clearcpuid); |
ac72e788 | 2005 | |
e57ef2ed TG |
2006 | DEFINE_PER_CPU_ALIGNED(struct pcpu_hot, pcpu_hot) = { |
2007 | .current_task = &init_task, | |
64701838 | 2008 | .preempt_count = INIT_PREEMPT_COUNT, |
c063a217 | 2009 | .top_of_stack = TOP_OF_INIT_STACK, |
e57ef2ed TG |
2010 | }; |
2011 | EXPORT_PER_CPU_SYMBOL(pcpu_hot); | |
2012 | ||
d5494d4f | 2013 | #ifdef CONFIG_X86_64 |
e6401c13 AL |
2014 | DEFINE_PER_CPU_FIRST(struct fixed_percpu_data, |
2015 | fixed_percpu_data) __aligned(PAGE_SIZE) __visible; | |
2016 | EXPORT_PER_CPU_SYMBOL_GPL(fixed_percpu_data); | |
0f3fa48a | 2017 | |
9c7e2634 AK |
2018 | static void wrmsrl_cstar(unsigned long val) |
2019 | { | |
2020 | /* | |
2021 | * Intel CPUs do not support 32-bit SYSCALL. Writing to MSR_CSTAR | |
2022 | * is so far ignored by the CPU, but raises a #VE trap in a TDX | |
2023 | * guest. Avoid the pointless write on all Intel CPUs. | |
2024 | */ | |
2025 | if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) | |
2026 | wrmsrl(MSR_CSTAR, val); | |
2027 | } | |
2028 | ||
d5494d4f YL |
2029 | /* May not be marked __init: used by software suspend */ |
2030 | void syscall_init(void) | |
1da177e4 | 2031 | { |
31ac34ca | 2032 | wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); |
bf904d27 | 2033 | wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64); |
d56fe4bf IM |
2034 | |
2035 | #ifdef CONFIG_IA32_EMULATION | |
9c7e2634 | 2036 | wrmsrl_cstar((unsigned long)entry_SYSCALL_compat); |
a76c7f46 | 2037 | /* |
487d1edb DV |
2038 | * This only works on Intel CPUs. |
2039 | * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP. | |
2040 | * This does not cause SYSENTER to jump to the wrong location, because | |
2041 | * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit). | |
a76c7f46 DV |
2042 | */ |
2043 | wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS); | |
8e6b65a1 | 2044 | wrmsrl_safe(MSR_IA32_SYSENTER_ESP, |
2045 | (unsigned long)(cpu_entry_stack(smp_processor_id()) + 1)); | |
4c8cd0c5 | 2046 | wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat); |
d56fe4bf | 2047 | #else |
9c7e2634 | 2048 | wrmsrl_cstar((unsigned long)ignore_sysret); |
6b51311c | 2049 | wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG); |
d56fe4bf IM |
2050 | wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL); |
2051 | wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL); | |
d5494d4f | 2052 | #endif |
03ae5768 | 2053 | |
6de4ac1d PAI |
2054 | /* |
2055 | * Flags to clear on syscall; clear as much as possible | |
2056 | * to minimize user space-kernel interference. | |
2057 | */ | |
d5494d4f | 2058 | wrmsrl(MSR_SYSCALL_MASK, |
6de4ac1d PAI |
2059 | X86_EFLAGS_CF|X86_EFLAGS_PF|X86_EFLAGS_AF| |
2060 | X86_EFLAGS_ZF|X86_EFLAGS_SF|X86_EFLAGS_TF| | |
2061 | X86_EFLAGS_IF|X86_EFLAGS_DF|X86_EFLAGS_OF| | |
2062 | X86_EFLAGS_IOPL|X86_EFLAGS_NT|X86_EFLAGS_RF| | |
2063 | X86_EFLAGS_AC|X86_EFLAGS_ID); | |
1da177e4 | 2064 | } |
62111195 | 2065 | |
0f3fa48a | 2066 | #else /* CONFIG_X86_64 */ |
d5494d4f | 2067 | |
050e9baa | 2068 | #ifdef CONFIG_STACKPROTECTOR |
3fb0fdb3 AL |
2069 | DEFINE_PER_CPU(unsigned long, __stack_chk_guard); |
2070 | EXPORT_PER_CPU_SYMBOL(__stack_chk_guard); | |
60a5317f | 2071 | #endif |
d5494d4f | 2072 | |
0f3fa48a | 2073 | #endif /* CONFIG_X86_64 */ |
c5413fbe | 2074 | |
9766cdbc JSR |
2075 | /* |
2076 | * Clear all 6 debug registers: | |
2077 | */ | |
2078 | static void clear_all_debug_regs(void) | |
2079 | { | |
2080 | int i; | |
2081 | ||
2082 | for (i = 0; i < 8; i++) { | |
2083 | /* Ignore db4, db5 */ | |
2084 | if ((i == 4) || (i == 5)) | |
2085 | continue; | |
2086 | ||
2087 | set_debugreg(0, i); | |
2088 | } | |
2089 | } | |
c5413fbe | 2090 | |
0bb9fef9 JW |
2091 | #ifdef CONFIG_KGDB |
2092 | /* | |
2093 | * Restore debug regs if using kgdbwait and you have a kernel debugger | |
2094 | * connection established. | |
2095 | */ | |
2096 | static void dbg_restore_debug_regs(void) | |
2097 | { | |
2098 | if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break)) | |
2099 | arch_kgdb_ops.correct_hw_break(); | |
2100 | } | |
2101 | #else /* ! CONFIG_KGDB */ | |
2102 | #define dbg_restore_debug_regs() | |
2103 | #endif /* ! CONFIG_KGDB */ | |
2104 | ||
505b7899 | 2105 | static inline void setup_getcpu(int cpu) |
b2e2ba57 | 2106 | { |
22245bdf | 2107 | unsigned long cpudata = vdso_encode_cpunode(cpu, early_cpu_to_node(cpu)); |
b2e2ba57 CB |
2108 | struct desc_struct d = { }; |
2109 | ||
b6b4fbd9 | 2110 | if (boot_cpu_has(X86_FEATURE_RDTSCP) || boot_cpu_has(X86_FEATURE_RDPID)) |
fc48a6d1 | 2111 | wrmsr(MSR_TSC_AUX, cpudata, 0); |
b2e2ba57 CB |
2112 | |
2113 | /* Store CPU and node number in limit. */ | |
2114 | d.limit0 = cpudata; | |
2115 | d.limit1 = cpudata >> 16; | |
2116 | ||
2117 | d.type = 5; /* RO data, expand down, accessed */ | |
2118 | d.dpl = 3; /* Visible to user code */ | |
2119 | d.s = 1; /* Not a system segment */ | |
2120 | d.p = 1; /* Present */ | |
2121 | d.d = 1; /* 32-bit */ | |
2122 | ||
22245bdf | 2123 | write_gdt_entry(get_cpu_gdt_rw(cpu), GDT_ENTRY_CPUNODE, &d, DESCTYPE_S); |
b2e2ba57 | 2124 | } |
505b7899 | 2125 | |
717cce3b | 2126 | #ifdef CONFIG_X86_64 |
0c7ffa32 | 2127 | static inline void ucode_cpu_init(int cpu) { } |
505b7899 TG |
2128 | |
2129 | static inline void tss_setup_ist(struct tss_struct *tss) | |
2130 | { | |
2131 | /* Set up the per-CPU TSS IST stacks */ | |
2132 | tss->x86_tss.ist[IST_INDEX_DF] = __this_cpu_ist_top_va(DF); | |
2133 | tss->x86_tss.ist[IST_INDEX_NMI] = __this_cpu_ist_top_va(NMI); | |
2134 | tss->x86_tss.ist[IST_INDEX_DB] = __this_cpu_ist_top_va(DB); | |
2135 | tss->x86_tss.ist[IST_INDEX_MCE] = __this_cpu_ist_top_va(MCE); | |
02772fb9 JR |
2136 | /* Only mapped when SEV-ES is active */ |
2137 | tss->x86_tss.ist[IST_INDEX_VC] = __this_cpu_ist_top_va(VC); | |
505b7899 TG |
2138 | } |
2139 | ||
505b7899 TG |
2140 | #else /* CONFIG_X86_64 */ |
2141 | ||
505b7899 TG |
2142 | static inline void ucode_cpu_init(int cpu) |
2143 | { | |
2144 | show_ucode_info_early(); | |
2145 | } | |
2146 | ||
2147 | static inline void tss_setup_ist(struct tss_struct *tss) { } | |
2148 | ||
505b7899 | 2149 | #endif /* !CONFIG_X86_64 */ |
b2e2ba57 | 2150 | |
111e7b15 TG |
2151 | static inline void tss_setup_io_bitmap(struct tss_struct *tss) |
2152 | { | |
2153 | tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET_INVALID; | |
2154 | ||
2155 | #ifdef CONFIG_X86_IOPL_IOPERM | |
2156 | tss->io_bitmap.prev_max = 0; | |
2157 | tss->io_bitmap.prev_sequence = 0; | |
2158 | memset(tss->io_bitmap.bitmap, 0xff, sizeof(tss->io_bitmap.bitmap)); | |
2159 | /* | |
2160 | * Invalidate the extra array entry past the end of the all | |
2161 | * permission bitmap as required by the hardware. | |
2162 | */ | |
2163 | tss->io_bitmap.mapall[IO_BITMAP_LONGS] = ~0UL; | |
b2e2ba57 | 2164 | #endif |
111e7b15 | 2165 | } |
b2e2ba57 | 2166 | |
520d0308 JR |
2167 | /* |
2168 | * Setup everything needed to handle exceptions from the IDT, including the IST | |
2169 | * exceptions which use paranoid_entry(). | |
2170 | */ | |
2171 | void cpu_init_exception_handling(void) | |
2172 | { | |
2173 | struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw); | |
2174 | int cpu = raw_smp_processor_id(); | |
2175 | ||
2176 | /* paranoid_entry() gets the CPU number from the GDT */ | |
2177 | setup_getcpu(cpu); | |
2178 | ||
2179 | /* IST vectors need TSS to be set up. */ | |
2180 | tss_setup_ist(tss); | |
2181 | tss_setup_io_bitmap(tss); | |
2182 | set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss); | |
2183 | ||
2184 | load_TR_desc(); | |
2185 | ||
95d33bfa BS |
2186 | /* GHCB needs to be setup to handle #VC. */ |
2187 | setup_ghcb(); | |
2188 | ||
520d0308 JR |
2189 | /* Finally load the IDT */ |
2190 | load_current_idt(); | |
2191 | } | |
2192 | ||
d2cbcc49 RR |
2193 | /* |
2194 | * cpu_init() initializes state that is per-CPU. Some data is already | |
b1efd0ff BP |
2195 | * initialized (naturally) in the bootstrap process, such as the GDT. We |
2196 | * reload it nevertheless, this function acts as a 'CPU state barrier', | |
2197 | * nothing should get across. | |
d2cbcc49 | 2198 | */ |
148f9bb8 | 2199 | void cpu_init(void) |
1ba76586 | 2200 | { |
505b7899 | 2201 | struct task_struct *cur = current; |
f6ef7322 | 2202 | int cpu = raw_smp_processor_id(); |
1ba76586 | 2203 | |
505b7899 | 2204 | ucode_cpu_init(cpu); |
0f3fa48a | 2205 | |
e7a22c1e | 2206 | #ifdef CONFIG_NUMA |
27fd185f | 2207 | if (this_cpu_read(numa_node) == 0 && |
e534c7c5 LS |
2208 | early_cpu_to_node(cpu) != NUMA_NO_NODE) |
2209 | set_numa_node(early_cpu_to_node(cpu)); | |
e7a22c1e | 2210 | #endif |
2eaad1fd | 2211 | pr_debug("Initializing CPU#%d\n", cpu); |
1ba76586 | 2212 | |
505b7899 TG |
2213 | if (IS_ENABLED(CONFIG_X86_64) || cpu_feature_enabled(X86_FEATURE_VME) || |
2214 | boot_cpu_has(X86_FEATURE_TSC) || boot_cpu_has(X86_FEATURE_DE)) | |
2215 | cr4_clear_bits(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE); | |
1ba76586 | 2216 | |
505b7899 TG |
2217 | if (IS_ENABLED(CONFIG_X86_64)) { |
2218 | loadsegment(fs, 0); | |
2219 | memset(cur->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8); | |
2220 | syscall_init(); | |
1ba76586 | 2221 | |
505b7899 TG |
2222 | wrmsrl(MSR_FS_BASE, 0); |
2223 | wrmsrl(MSR_KERNEL_GS_BASE, 0); | |
2224 | barrier(); | |
1ba76586 | 2225 | |
505b7899 | 2226 | x2apic_setup(); |
1ba76586 YL |
2227 | } |
2228 | ||
f1f10076 | 2229 | mmgrab(&init_mm); |
505b7899 TG |
2230 | cur->active_mm = &init_mm; |
2231 | BUG_ON(cur->mm); | |
72c0098d | 2232 | initialize_tlbstate_and_flush(); |
505b7899 | 2233 | enter_lazy_tlb(&init_mm, cur); |
1ba76586 | 2234 | |
505b7899 TG |
2235 | /* |
2236 | * sp0 points to the entry trampoline stack regardless of what task | |
2237 | * is running. | |
2238 | */ | |
4fe2d8b1 | 2239 | load_sp0((unsigned long)(cpu_entry_stack(cpu) + 1)); |
20bb8344 | 2240 | |
37868fe1 | 2241 | load_mm_ldt(&init_mm); |
1ba76586 | 2242 | |
0bb9fef9 JW |
2243 | clear_all_debug_regs(); |
2244 | dbg_restore_debug_regs(); | |
1ba76586 | 2245 | |
dc4e0021 | 2246 | doublefault_init_cpu_tss(); |
505b7899 | 2247 | |
1ba76586 YL |
2248 | if (is_uv_system()) |
2249 | uv_cpu_init(); | |
69218e47 | 2250 | |
69218e47 | 2251 | load_fixmap_gdt(cpu); |
1ba76586 YL |
2252 | } |
2253 | ||
a77a94f8 | 2254 | #ifdef CONFIG_MICROCODE_LATE_LOADING |
c0dd9245 AR |
2255 | /** |
2256 | * store_cpu_caps() - Store a snapshot of CPU capabilities | |
2257 | * @curr_info: Pointer where to store it | |
2258 | * | |
2259 | * Returns: None | |
2260 | */ | |
2261 | void store_cpu_caps(struct cpuinfo_x86 *curr_info) | |
2262 | { | |
2263 | /* Reload CPUID max function as it might've changed. */ | |
2264 | curr_info->cpuid_level = cpuid_eax(0); | |
2265 | ||
2266 | /* Copy all capability leafs and pick up the synthetic ones. */ | |
2267 | memcpy(&curr_info->x86_capability, &boot_cpu_data.x86_capability, | |
2268 | sizeof(curr_info->x86_capability)); | |
2269 | ||
2270 | /* Get the hardware CPUID leafs */ | |
2271 | get_cpu_cap(curr_info); | |
2272 | } | |
2273 | ||
ab31c744 AR |
2274 | /** |
2275 | * microcode_check() - Check if any CPU capabilities changed after an update. | |
2276 | * @prev_info: CPU capabilities stored before an update. | |
2277 | * | |
1008c52c BP |
2278 | * The microcode loader calls this upon late microcode load to recheck features, |
2279 | * only when microcode has been updated. Caller holds microcode_mutex and CPU | |
2280 | * hotplug lock. | |
ab31c744 AR |
2281 | * |
2282 | * Return: None | |
1008c52c | 2283 | */ |
ab31c744 | 2284 | void microcode_check(struct cpuinfo_x86 *prev_info) |
1008c52c | 2285 | { |
c0dd9245 | 2286 | struct cpuinfo_x86 curr_info; |
42ca8082 | 2287 | |
1008c52c | 2288 | perf_check_microcode(); |
42ca8082 | 2289 | |
c0dd9245 | 2290 | store_cpu_caps(&curr_info); |
42ca8082 | 2291 | |
c0dd9245 | 2292 | if (!memcmp(&prev_info->x86_capability, &curr_info.x86_capability, |
ab31c744 | 2293 | sizeof(prev_info->x86_capability))) |
42ca8082 BP |
2294 | return; |
2295 | ||
2296 | pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n"); | |
2297 | pr_warn("x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update.\n"); | |
1008c52c | 2298 | } |
a77a94f8 | 2299 | #endif |
9c92374b TG |
2300 | |
2301 | /* | |
2302 | * Invoked from core CPU hotplug code after hotplug operations | |
2303 | */ | |
2304 | void arch_smt_update(void) | |
2305 | { | |
2306 | /* Handle the speculative execution misfeatures */ | |
2307 | cpu_bugs_smt_update(); | |
6a1cb5f5 TG |
2308 | /* Check whether IPI broadcasting can be enabled */ |
2309 | apic_smt_update(); | |
9c92374b | 2310 | } |
7c7077a7 TG |
2311 | |
2312 | void __init arch_cpu_finalize_init(void) | |
2313 | { | |
2314 | identify_boot_cpu(); | |
2315 | ||
2316 | /* | |
2317 | * identify_boot_cpu() initialized SMT support information, let the | |
2318 | * core code know. | |
2319 | */ | |
2320 | cpu_smt_check_topology(); | |
2321 | ||
2322 | if (!IS_ENABLED(CONFIG_SMP)) { | |
2323 | pr_info("CPU: "); | |
2324 | print_cpu_info(&boot_cpu_data); | |
2325 | } | |
2326 | ||
2327 | cpu_select_mitigations(); | |
2328 | ||
2329 | arch_smt_update(); | |
2330 | ||
2331 | if (IS_ENABLED(CONFIG_X86_32)) { | |
2332 | /* | |
2333 | * Check whether this is a real i386 which is not longer | |
2334 | * supported and fixup the utsname. | |
2335 | */ | |
2336 | if (boot_cpu_data.x86 < 4) | |
2337 | panic("Kernel requires i486+ for 'invlpg' and other features"); | |
2338 | ||
2339 | init_utsname()->machine[1] = | |
2340 | '0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86); | |
2341 | } | |
2342 | ||
b81fac90 TG |
2343 | /* |
2344 | * Must be before alternatives because it might set or clear | |
2345 | * feature bits. | |
2346 | */ | |
2347 | fpu__init_system(); | |
2348 | fpu__init_cpu(); | |
2349 | ||
7c7077a7 TG |
2350 | alternative_instructions(); |
2351 | ||
2352 | if (IS_ENABLED(CONFIG_X86_64)) { | |
2353 | /* | |
2354 | * Make sure the first 2MB area is not mapped by huge pages | |
2355 | * There are typically fixed size MTRRs in there and overlapping | |
2356 | * MTRRs into large pages causes slow downs. | |
2357 | * | |
2358 | * Right now we don't do that with gbpages because there seems | |
2359 | * very little benefit for that case. | |
2360 | */ | |
2361 | if (!direct_gbpages) | |
2362 | set_memory_4k((unsigned long)__va(0), 1); | |
2363 | } else { | |
2364 | fpu__init_check_bugs(); | |
2365 | } | |
439e1757 TG |
2366 | |
2367 | /* | |
2368 | * This needs to be called before any devices perform DMA | |
2369 | * operations that might use the SWIOTLB bounce buffers. It will | |
2370 | * mark the bounce buffers as decrypted so that their usage will | |
2371 | * not cause "plain-text" data to be decrypted when accessed. It | |
2372 | * must be called after late_time_init() so that Hyper-V x86/x64 | |
2373 | * hypercalls work when the SWIOTLB bounce buffers are decrypted. | |
2374 | */ | |
2375 | mem_encrypt_init(); | |
7c7077a7 | 2376 | } |