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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Intel CPU Microcode Update Driver for Linux
4 *
5 * Copyright (C) 2000-2006 Tigran Aivazian <aivazian.tigran@gmail.com>
6 * 2006 Shaohua Li <shaohua.li@intel.com>
7 *
8 * Intel CPU microcode early update for Linux
9 *
10 * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
11 * H Peter Anvin" <hpa@zytor.com>
12 */
13
14/*
15 * This needs to be before all headers so that pr_debug in printk.h doesn't turn
16 * printk calls into no_printk().
17 *
18 *#define DEBUG
19 */
20#define pr_fmt(fmt) "microcode: " fmt
21
22#include <linux/earlycpio.h>
23#include <linux/firmware.h>
24#include <linux/uaccess.h>
25#include <linux/vmalloc.h>
26#include <linux/initrd.h>
27#include <linux/kernel.h>
28#include <linux/slab.h>
29#include <linux/cpu.h>
30#include <linux/uio.h>
31#include <linux/mm.h>
32
33#include <asm/microcode_intel.h>
34#include <asm/intel-family.h>
35#include <asm/processor.h>
36#include <asm/tlbflush.h>
37#include <asm/setup.h>
38#include <asm/msr.h>
39
40static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
41
42/* Current microcode patch used in early patching on the APs. */
43static struct microcode_intel *intel_ucode_patch;
44
45/* last level cache size per core */
46static int llc_size_per_core;
47
48static inline bool cpu_signatures_match(unsigned int s1, unsigned int p1,
49 unsigned int s2, unsigned int p2)
50{
51 if (s1 != s2)
52 return false;
53
54 /* Processor flags are either both 0 ... */
55 if (!p1 && !p2)
56 return true;
57
58 /* ... or they intersect. */
59 return p1 & p2;
60}
61
62/*
63 * Returns 1 if update has been found, 0 otherwise.
64 */
65static int find_matching_signature(void *mc, unsigned int csig, int cpf)
66{
67 struct microcode_header_intel *mc_hdr = mc;
68 struct extended_sigtable *ext_hdr;
69 struct extended_signature *ext_sig;
70 int i;
71
72 if (cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf))
73 return 1;
74
75 /* Look for ext. headers: */
76 if (get_totalsize(mc_hdr) <= get_datasize(mc_hdr) + MC_HEADER_SIZE)
77 return 0;
78
79 ext_hdr = mc + get_datasize(mc_hdr) + MC_HEADER_SIZE;
80 ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE;
81
82 for (i = 0; i < ext_hdr->count; i++) {
83 if (cpu_signatures_match(csig, cpf, ext_sig->sig, ext_sig->pf))
84 return 1;
85 ext_sig++;
86 }
87 return 0;
88}
89
90/*
91 * Returns 1 if update has been found, 0 otherwise.
92 */
93static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev)
94{
95 struct microcode_header_intel *mc_hdr = mc;
96
97 if (mc_hdr->rev <= new_rev)
98 return 0;
99
100 return find_matching_signature(mc, csig, cpf);
101}
102
103/*
104 * Given CPU signature and a microcode patch, this function finds if the
105 * microcode patch has matching family and model with the CPU.
106 *
107 * %true - if there's a match
108 * %false - otherwise
109 */
110static bool microcode_matches(struct microcode_header_intel *mc_header,
111 unsigned long sig)
112{
113 unsigned long total_size = get_totalsize(mc_header);
114 unsigned long data_size = get_datasize(mc_header);
115 struct extended_sigtable *ext_header;
116 unsigned int fam_ucode, model_ucode;
117 struct extended_signature *ext_sig;
118 unsigned int fam, model;
119 int ext_sigcount, i;
120
121 fam = x86_family(sig);
122 model = x86_model(sig);
123
124 fam_ucode = x86_family(mc_header->sig);
125 model_ucode = x86_model(mc_header->sig);
126
127 if (fam == fam_ucode && model == model_ucode)
128 return true;
129
130 /* Look for ext. headers: */
131 if (total_size <= data_size + MC_HEADER_SIZE)
132 return false;
133
134 ext_header = (void *) mc_header + data_size + MC_HEADER_SIZE;
135 ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
136 ext_sigcount = ext_header->count;
137
138 for (i = 0; i < ext_sigcount; i++) {
139 fam_ucode = x86_family(ext_sig->sig);
140 model_ucode = x86_model(ext_sig->sig);
141
142 if (fam == fam_ucode && model == model_ucode)
143 return true;
144
145 ext_sig++;
146 }
147 return false;
148}
149
150static struct ucode_patch *memdup_patch(void *data, unsigned int size)
151{
152 struct ucode_patch *p;
153
154 p = kzalloc(sizeof(struct ucode_patch), GFP_KERNEL);
155 if (!p)
156 return NULL;
157
158 p->data = kmemdup(data, size, GFP_KERNEL);
159 if (!p->data) {
160 kfree(p);
161 return NULL;
162 }
163
164 return p;
165}
166
167static void save_microcode_patch(void *data, unsigned int size)
168{
169 struct microcode_header_intel *mc_hdr, *mc_saved_hdr;
170 struct ucode_patch *iter, *tmp, *p = NULL;
171 bool prev_found = false;
172 unsigned int sig, pf;
173
174 mc_hdr = (struct microcode_header_intel *)data;
175
176 list_for_each_entry_safe(iter, tmp, µcode_cache, plist) {
177 mc_saved_hdr = (struct microcode_header_intel *)iter->data;
178 sig = mc_saved_hdr->sig;
179 pf = mc_saved_hdr->pf;
180
181 if (find_matching_signature(data, sig, pf)) {
182 prev_found = true;
183
184 if (mc_hdr->rev <= mc_saved_hdr->rev)
185 continue;
186
187 p = memdup_patch(data, size);
188 if (!p)
189 pr_err("Error allocating buffer %p\n", data);
190 else {
191 list_replace(&iter->plist, &p->plist);
192 kfree(iter->data);
193 kfree(iter);
194 }
195 }
196 }
197
198 /*
199 * There weren't any previous patches found in the list cache; save the
200 * newly found.
201 */
202 if (!prev_found) {
203 p = memdup_patch(data, size);
204 if (!p)
205 pr_err("Error allocating buffer for %p\n", data);
206 else
207 list_add_tail(&p->plist, µcode_cache);
208 }
209
210 if (!p)
211 return;
212
213 /*
214 * Save for early loading. On 32-bit, that needs to be a physical
215 * address as the APs are running from physical addresses, before
216 * paging has been enabled.
217 */
218 if (IS_ENABLED(CONFIG_X86_32))
219 intel_ucode_patch = (struct microcode_intel *)__pa_nodebug(p->data);
220 else
221 intel_ucode_patch = p->data;
222}
223
224static int microcode_sanity_check(void *mc, int print_err)
225{
226 unsigned long total_size, data_size, ext_table_size;
227 struct microcode_header_intel *mc_header = mc;
228 struct extended_sigtable *ext_header = NULL;
229 u32 sum, orig_sum, ext_sigcount = 0, i;
230 struct extended_signature *ext_sig;
231
232 total_size = get_totalsize(mc_header);
233 data_size = get_datasize(mc_header);
234
235 if (data_size + MC_HEADER_SIZE > total_size) {
236 if (print_err)
237 pr_err("Error: bad microcode data file size.\n");
238 return -EINVAL;
239 }
240
241 if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
242 if (print_err)
243 pr_err("Error: invalid/unknown microcode update format.\n");
244 return -EINVAL;
245 }
246
247 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
248 if (ext_table_size) {
249 u32 ext_table_sum = 0;
250 u32 *ext_tablep;
251
252 if ((ext_table_size < EXT_HEADER_SIZE)
253 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
254 if (print_err)
255 pr_err("Error: truncated extended signature table.\n");
256 return -EINVAL;
257 }
258
259 ext_header = mc + MC_HEADER_SIZE + data_size;
260 if (ext_table_size != exttable_size(ext_header)) {
261 if (print_err)
262 pr_err("Error: extended signature table size mismatch.\n");
263 return -EFAULT;
264 }
265
266 ext_sigcount = ext_header->count;
267
268 /*
269 * Check extended table checksum: the sum of all dwords that
270 * comprise a valid table must be 0.
271 */
272 ext_tablep = (u32 *)ext_header;
273
274 i = ext_table_size / sizeof(u32);
275 while (i--)
276 ext_table_sum += ext_tablep[i];
277
278 if (ext_table_sum) {
279 if (print_err)
280 pr_warn("Bad extended signature table checksum, aborting.\n");
281 return -EINVAL;
282 }
283 }
284
285 /*
286 * Calculate the checksum of update data and header. The checksum of
287 * valid update data and header including the extended signature table
288 * must be 0.
289 */
290 orig_sum = 0;
291 i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
292 while (i--)
293 orig_sum += ((u32 *)mc)[i];
294
295 if (orig_sum) {
296 if (print_err)
297 pr_err("Bad microcode data checksum, aborting.\n");
298 return -EINVAL;
299 }
300
301 if (!ext_table_size)
302 return 0;
303
304 /*
305 * Check extended signature checksum: 0 => valid.
306 */
307 for (i = 0; i < ext_sigcount; i++) {
308 ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
309 EXT_SIGNATURE_SIZE * i;
310
311 sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
312 (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
313 if (sum) {
314 if (print_err)
315 pr_err("Bad extended signature checksum, aborting.\n");
316 return -EINVAL;
317 }
318 }
319 return 0;
320}
321
322/*
323 * Get microcode matching with BSP's model. Only CPUs with the same model as
324 * BSP can stay in the platform.
325 */
326static struct microcode_intel *
327scan_microcode(void *data, size_t size, struct ucode_cpu_info *uci, bool save)
328{
329 struct microcode_header_intel *mc_header;
330 struct microcode_intel *patch = NULL;
331 unsigned int mc_size;
332
333 while (size) {
334 if (size < sizeof(struct microcode_header_intel))
335 break;
336
337 mc_header = (struct microcode_header_intel *)data;
338
339 mc_size = get_totalsize(mc_header);
340 if (!mc_size ||
341 mc_size > size ||
342 microcode_sanity_check(data, 0) < 0)
343 break;
344
345 size -= mc_size;
346
347 if (!microcode_matches(mc_header, uci->cpu_sig.sig)) {
348 data += mc_size;
349 continue;
350 }
351
352 if (save) {
353 save_microcode_patch(data, mc_size);
354 goto next;
355 }
356
357
358 if (!patch) {
359 if (!has_newer_microcode(data,
360 uci->cpu_sig.sig,
361 uci->cpu_sig.pf,
362 uci->cpu_sig.rev))
363 goto next;
364
365 } else {
366 struct microcode_header_intel *phdr = &patch->hdr;
367
368 if (!has_newer_microcode(data,
369 phdr->sig,
370 phdr->pf,
371 phdr->rev))
372 goto next;
373 }
374
375 /* We have a newer patch, save it. */
376 patch = data;
377
378next:
379 data += mc_size;
380 }
381
382 if (size)
383 return NULL;
384
385 return patch;
386}
387
388static int collect_cpu_info_early(struct ucode_cpu_info *uci)
389{
390 unsigned int val[2];
391 unsigned int family, model;
392 struct cpu_signature csig = { 0 };
393 unsigned int eax, ebx, ecx, edx;
394
395 memset(uci, 0, sizeof(*uci));
396
397 eax = 0x00000001;
398 ecx = 0;
399 native_cpuid(&eax, &ebx, &ecx, &edx);
400 csig.sig = eax;
401
402 family = x86_family(eax);
403 model = x86_model(eax);
404
405 if ((model >= 5) || (family > 6)) {
406 /* get processor flags from MSR 0x17 */
407 native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
408 csig.pf = 1 << ((val[1] >> 18) & 7);
409 }
410
411 csig.rev = intel_get_microcode_revision();
412
413 uci->cpu_sig = csig;
414 uci->valid = 1;
415
416 return 0;
417}
418
419static void show_saved_mc(void)
420{
421#ifdef DEBUG
422 int i = 0, j;
423 unsigned int sig, pf, rev, total_size, data_size, date;
424 struct ucode_cpu_info uci;
425 struct ucode_patch *p;
426
427 if (list_empty(µcode_cache)) {
428 pr_debug("no microcode data saved.\n");
429 return;
430 }
431
432 collect_cpu_info_early(&uci);
433
434 sig = uci.cpu_sig.sig;
435 pf = uci.cpu_sig.pf;
436 rev = uci.cpu_sig.rev;
437 pr_debug("CPU: sig=0x%x, pf=0x%x, rev=0x%x\n", sig, pf, rev);
438
439 list_for_each_entry(p, µcode_cache, plist) {
440 struct microcode_header_intel *mc_saved_header;
441 struct extended_sigtable *ext_header;
442 struct extended_signature *ext_sig;
443 int ext_sigcount;
444
445 mc_saved_header = (struct microcode_header_intel *)p->data;
446
447 sig = mc_saved_header->sig;
448 pf = mc_saved_header->pf;
449 rev = mc_saved_header->rev;
450 date = mc_saved_header->date;
451
452 total_size = get_totalsize(mc_saved_header);
453 data_size = get_datasize(mc_saved_header);
454
455 pr_debug("mc_saved[%d]: sig=0x%x, pf=0x%x, rev=0x%x, total size=0x%x, date = %04x-%02x-%02x\n",
456 i++, sig, pf, rev, total_size,
457 date & 0xffff,
458 date >> 24,
459 (date >> 16) & 0xff);
460
461 /* Look for ext. headers: */
462 if (total_size <= data_size + MC_HEADER_SIZE)
463 continue;
464
465 ext_header = (void *)mc_saved_header + data_size + MC_HEADER_SIZE;
466 ext_sigcount = ext_header->count;
467 ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
468
469 for (j = 0; j < ext_sigcount; j++) {
470 sig = ext_sig->sig;
471 pf = ext_sig->pf;
472
473 pr_debug("\tExtended[%d]: sig=0x%x, pf=0x%x\n",
474 j, sig, pf);
475
476 ext_sig++;
477 }
478 }
479#endif
480}
481
482/*
483 * Save this microcode patch. It will be loaded early when a CPU is
484 * hot-added or resumes.
485 */
486static void save_mc_for_early(u8 *mc, unsigned int size)
487{
488 /* Synchronization during CPU hotplug. */
489 static DEFINE_MUTEX(x86_cpu_microcode_mutex);
490
491 mutex_lock(&x86_cpu_microcode_mutex);
492
493 save_microcode_patch(mc, size);
494 show_saved_mc();
495
496 mutex_unlock(&x86_cpu_microcode_mutex);
497}
498
499static bool load_builtin_intel_microcode(struct cpio_data *cp)
500{
501 unsigned int eax = 1, ebx, ecx = 0, edx;
502 char name[30];
503
504 if (IS_ENABLED(CONFIG_X86_32))
505 return false;
506
507 native_cpuid(&eax, &ebx, &ecx, &edx);
508
509 sprintf(name, "intel-ucode/%02x-%02x-%02x",
510 x86_family(eax), x86_model(eax), x86_stepping(eax));
511
512 return get_builtin_firmware(cp, name);
513}
514
515/*
516 * Print ucode update info.
517 */
518static void
519print_ucode_info(struct ucode_cpu_info *uci, unsigned int date)
520{
521 pr_info_once("microcode updated early to revision 0x%x, date = %04x-%02x-%02x\n",
522 uci->cpu_sig.rev,
523 date & 0xffff,
524 date >> 24,
525 (date >> 16) & 0xff);
526}
527
528#ifdef CONFIG_X86_32
529
530static int delay_ucode_info;
531static int current_mc_date;
532
533/*
534 * Print early updated ucode info after printk works. This is delayed info dump.
535 */
536void show_ucode_info_early(void)
537{
538 struct ucode_cpu_info uci;
539
540 if (delay_ucode_info) {
541 collect_cpu_info_early(&uci);
542 print_ucode_info(&uci, current_mc_date);
543 delay_ucode_info = 0;
544 }
545}
546
547/*
548 * At this point, we can not call printk() yet. Delay printing microcode info in
549 * show_ucode_info_early() until printk() works.
550 */
551static void print_ucode(struct ucode_cpu_info *uci)
552{
553 struct microcode_intel *mc;
554 int *delay_ucode_info_p;
555 int *current_mc_date_p;
556
557 mc = uci->mc;
558 if (!mc)
559 return;
560
561 delay_ucode_info_p = (int *)__pa_nodebug(&delay_ucode_info);
562 current_mc_date_p = (int *)__pa_nodebug(¤t_mc_date);
563
564 *delay_ucode_info_p = 1;
565 *current_mc_date_p = mc->hdr.date;
566}
567#else
568
569static inline void print_ucode(struct ucode_cpu_info *uci)
570{
571 struct microcode_intel *mc;
572
573 mc = uci->mc;
574 if (!mc)
575 return;
576
577 print_ucode_info(uci, mc->hdr.date);
578}
579#endif
580
581static int apply_microcode_early(struct ucode_cpu_info *uci, bool early)
582{
583 struct microcode_intel *mc;
584 u32 rev;
585
586 mc = uci->mc;
587 if (!mc)
588 return 0;
589
590 /*
591 * Save us the MSR write below - which is a particular expensive
592 * operation - when the other hyperthread has updated the microcode
593 * already.
594 */
595 rev = intel_get_microcode_revision();
596 if (rev >= mc->hdr.rev) {
597 uci->cpu_sig.rev = rev;
598 return UCODE_OK;
599 }
600
601 /*
602 * Writeback and invalidate caches before updating microcode to avoid
603 * internal issues depending on what the microcode is updating.
604 */
605 native_wbinvd();
606
607 /* write microcode via MSR 0x79 */
608 native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
609
610 rev = intel_get_microcode_revision();
611 if (rev != mc->hdr.rev)
612 return -1;
613
614 uci->cpu_sig.rev = rev;
615
616 if (early)
617 print_ucode(uci);
618 else
619 print_ucode_info(uci, mc->hdr.date);
620
621 return 0;
622}
623
624int __init save_microcode_in_initrd_intel(void)
625{
626 struct ucode_cpu_info uci;
627 struct cpio_data cp;
628
629 /*
630 * initrd is going away, clear patch ptr. We will scan the microcode one
631 * last time before jettisoning and save a patch, if found. Then we will
632 * update that pointer too, with a stable patch address to use when
633 * resuming the cores.
634 */
635 intel_ucode_patch = NULL;
636
637 if (!load_builtin_intel_microcode(&cp))
638 cp = find_microcode_in_initrd(ucode_path, false);
639
640 if (!(cp.data && cp.size))
641 return 0;
642
643 collect_cpu_info_early(&uci);
644
645 scan_microcode(cp.data, cp.size, &uci, true);
646
647 show_saved_mc();
648
649 return 0;
650}
651
652/*
653 * @res_patch, output: a pointer to the patch we found.
654 */
655static struct microcode_intel *__load_ucode_intel(struct ucode_cpu_info *uci)
656{
657 static const char *path;
658 struct cpio_data cp;
659 bool use_pa;
660
661 if (IS_ENABLED(CONFIG_X86_32)) {
662 path = (const char *)__pa_nodebug(ucode_path);
663 use_pa = true;
664 } else {
665 path = ucode_path;
666 use_pa = false;
667 }
668
669 /* try built-in microcode first */
670 if (!load_builtin_intel_microcode(&cp))
671 cp = find_microcode_in_initrd(path, use_pa);
672
673 if (!(cp.data && cp.size))
674 return NULL;
675
676 collect_cpu_info_early(uci);
677
678 return scan_microcode(cp.data, cp.size, uci, false);
679}
680
681void __init load_ucode_intel_bsp(void)
682{
683 struct microcode_intel *patch;
684 struct ucode_cpu_info uci;
685
686 patch = __load_ucode_intel(&uci);
687 if (!patch)
688 return;
689
690 uci.mc = patch;
691
692 apply_microcode_early(&uci, true);
693}
694
695void load_ucode_intel_ap(void)
696{
697 struct microcode_intel *patch, **iup;
698 struct ucode_cpu_info uci;
699
700 if (IS_ENABLED(CONFIG_X86_32))
701 iup = (struct microcode_intel **) __pa_nodebug(&intel_ucode_patch);
702 else
703 iup = &intel_ucode_patch;
704
705reget:
706 if (!*iup) {
707 patch = __load_ucode_intel(&uci);
708 if (!patch)
709 return;
710
711 *iup = patch;
712 }
713
714 uci.mc = *iup;
715
716 if (apply_microcode_early(&uci, true)) {
717 /* Mixed-silicon system? Try to refetch the proper patch: */
718 *iup = NULL;
719
720 goto reget;
721 }
722}
723
724static struct microcode_intel *find_patch(struct ucode_cpu_info *uci)
725{
726 struct microcode_header_intel *phdr;
727 struct ucode_patch *iter, *tmp;
728
729 list_for_each_entry_safe(iter, tmp, µcode_cache, plist) {
730
731 phdr = (struct microcode_header_intel *)iter->data;
732
733 if (phdr->rev <= uci->cpu_sig.rev)
734 continue;
735
736 if (!find_matching_signature(phdr,
737 uci->cpu_sig.sig,
738 uci->cpu_sig.pf))
739 continue;
740
741 return iter->data;
742 }
743 return NULL;
744}
745
746void reload_ucode_intel(void)
747{
748 struct microcode_intel *p;
749 struct ucode_cpu_info uci;
750
751 collect_cpu_info_early(&uci);
752
753 p = find_patch(&uci);
754 if (!p)
755 return;
756
757 uci.mc = p;
758
759 apply_microcode_early(&uci, false);
760}
761
762static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
763{
764 static struct cpu_signature prev;
765 struct cpuinfo_x86 *c = &cpu_data(cpu_num);
766 unsigned int val[2];
767
768 memset(csig, 0, sizeof(*csig));
769
770 csig->sig = cpuid_eax(0x00000001);
771
772 if ((c->x86_model >= 5) || (c->x86 > 6)) {
773 /* get processor flags from MSR 0x17 */
774 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
775 csig->pf = 1 << ((val[1] >> 18) & 7);
776 }
777
778 csig->rev = c->microcode;
779
780 /* No extra locking on prev, races are harmless. */
781 if (csig->sig != prev.sig || csig->pf != prev.pf || csig->rev != prev.rev) {
782 pr_info("sig=0x%x, pf=0x%x, revision=0x%x\n",
783 csig->sig, csig->pf, csig->rev);
784 prev = *csig;
785 }
786
787 return 0;
788}
789
790static enum ucode_state apply_microcode_intel(int cpu)
791{
792 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
793 struct cpuinfo_x86 *c = &cpu_data(cpu);
794 struct microcode_intel *mc;
795 enum ucode_state ret;
796 static int prev_rev;
797 u32 rev;
798
799 /* We should bind the task to the CPU */
800 if (WARN_ON(raw_smp_processor_id() != cpu))
801 return UCODE_ERROR;
802
803 /* Look for a newer patch in our cache: */
804 mc = find_patch(uci);
805 if (!mc) {
806 mc = uci->mc;
807 if (!mc)
808 return UCODE_NFOUND;
809 }
810
811 /*
812 * Save us the MSR write below - which is a particular expensive
813 * operation - when the other hyperthread has updated the microcode
814 * already.
815 */
816 rev = intel_get_microcode_revision();
817 if (rev >= mc->hdr.rev) {
818 ret = UCODE_OK;
819 goto out;
820 }
821
822 /*
823 * Writeback and invalidate caches before updating microcode to avoid
824 * internal issues depending on what the microcode is updating.
825 */
826 native_wbinvd();
827
828 /* write microcode via MSR 0x79 */
829 wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
830
831 rev = intel_get_microcode_revision();
832
833 if (rev != mc->hdr.rev) {
834 pr_err("CPU%d update to revision 0x%x failed\n",
835 cpu, mc->hdr.rev);
836 return UCODE_ERROR;
837 }
838
839 if (rev != prev_rev) {
840 pr_info("updated to revision 0x%x, date = %04x-%02x-%02x\n",
841 rev,
842 mc->hdr.date & 0xffff,
843 mc->hdr.date >> 24,
844 (mc->hdr.date >> 16) & 0xff);
845 prev_rev = rev;
846 }
847
848 ret = UCODE_UPDATED;
849
850out:
851 uci->cpu_sig.rev = rev;
852 c->microcode = rev;
853
854 /* Update boot_cpu_data's revision too, if we're on the BSP: */
855 if (c->cpu_index == boot_cpu_data.cpu_index)
856 boot_cpu_data.microcode = rev;
857
858 return ret;
859}
860
861static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
862{
863 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
864 unsigned int curr_mc_size = 0, new_mc_size = 0;
865 enum ucode_state ret = UCODE_OK;
866 int new_rev = uci->cpu_sig.rev;
867 u8 *new_mc = NULL, *mc = NULL;
868 unsigned int csig, cpf;
869
870 while (iov_iter_count(iter)) {
871 struct microcode_header_intel mc_header;
872 unsigned int mc_size, data_size;
873 u8 *data;
874
875 if (!copy_from_iter_full(&mc_header, sizeof(mc_header), iter)) {
876 pr_err("error! Truncated or inaccessible header in microcode data file\n");
877 break;
878 }
879
880 mc_size = get_totalsize(&mc_header);
881 if (mc_size < sizeof(mc_header)) {
882 pr_err("error! Bad data in microcode data file (totalsize too small)\n");
883 break;
884 }
885 data_size = mc_size - sizeof(mc_header);
886 if (data_size > iov_iter_count(iter)) {
887 pr_err("error! Bad data in microcode data file (truncated file?)\n");
888 break;
889 }
890
891 /* For performance reasons, reuse mc area when possible */
892 if (!mc || mc_size > curr_mc_size) {
893 vfree(mc);
894 mc = vmalloc(mc_size);
895 if (!mc)
896 break;
897 curr_mc_size = mc_size;
898 }
899
900 memcpy(mc, &mc_header, sizeof(mc_header));
901 data = mc + sizeof(mc_header);
902 if (!copy_from_iter_full(data, data_size, iter) ||
903 microcode_sanity_check(mc, 1) < 0) {
904 break;
905 }
906
907 csig = uci->cpu_sig.sig;
908 cpf = uci->cpu_sig.pf;
909 if (has_newer_microcode(mc, csig, cpf, new_rev)) {
910 vfree(new_mc);
911 new_rev = mc_header.rev;
912 new_mc = mc;
913 new_mc_size = mc_size;
914 mc = NULL; /* trigger new vmalloc */
915 ret = UCODE_NEW;
916 }
917 }
918
919 vfree(mc);
920
921 if (iov_iter_count(iter)) {
922 vfree(new_mc);
923 return UCODE_ERROR;
924 }
925
926 if (!new_mc)
927 return UCODE_NFOUND;
928
929 vfree(uci->mc);
930 uci->mc = (struct microcode_intel *)new_mc;
931
932 /*
933 * If early loading microcode is supported, save this mc into
934 * permanent memory. So it will be loaded early when a CPU is hot added
935 * or resumes.
936 */
937 save_mc_for_early(new_mc, new_mc_size);
938
939 pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
940 cpu, new_rev, uci->cpu_sig.rev);
941
942 return ret;
943}
944
945static bool is_blacklisted(unsigned int cpu)
946{
947 struct cpuinfo_x86 *c = &cpu_data(cpu);
948
949 /*
950 * Late loading on model 79 with microcode revision less than 0x0b000021
951 * and LLC size per core bigger than 2.5MB may result in a system hang.
952 * This behavior is documented in item BDF90, #334165 (Intel Xeon
953 * Processor E7-8800/4800 v4 Product Family).
954 */
955 if (c->x86 == 6 &&
956 c->x86_model == INTEL_FAM6_BROADWELL_X &&
957 c->x86_stepping == 0x01 &&
958 llc_size_per_core > 2621440 &&
959 c->microcode < 0x0b000021) {
960 pr_err_once("Erratum BDF90: late loading with revision < 0x0b000021 (0x%x) disabled.\n", c->microcode);
961 pr_err_once("Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
962 return true;
963 }
964
965 return false;
966}
967
968static enum ucode_state request_microcode_fw(int cpu, struct device *device,
969 bool refresh_fw)
970{
971 struct cpuinfo_x86 *c = &cpu_data(cpu);
972 const struct firmware *firmware;
973 struct iov_iter iter;
974 enum ucode_state ret;
975 struct kvec kvec;
976 char name[30];
977
978 if (is_blacklisted(cpu))
979 return UCODE_NFOUND;
980
981 sprintf(name, "intel-ucode/%02x-%02x-%02x",
982 c->x86, c->x86_model, c->x86_stepping);
983
984 if (request_firmware_direct(&firmware, name, device)) {
985 pr_debug("data file %s load failed\n", name);
986 return UCODE_NFOUND;
987 }
988
989 kvec.iov_base = (void *)firmware->data;
990 kvec.iov_len = firmware->size;
991 iov_iter_kvec(&iter, WRITE, &kvec, 1, firmware->size);
992 ret = generic_load_microcode(cpu, &iter);
993
994 release_firmware(firmware);
995
996 return ret;
997}
998
999static enum ucode_state
1000request_microcode_user(int cpu, const void __user *buf, size_t size)
1001{
1002 struct iov_iter iter;
1003 struct iovec iov;
1004
1005 if (is_blacklisted(cpu))
1006 return UCODE_NFOUND;
1007
1008 iov.iov_base = (void __user *)buf;
1009 iov.iov_len = size;
1010 iov_iter_init(&iter, WRITE, &iov, 1, size);
1011
1012 return generic_load_microcode(cpu, &iter);
1013}
1014
1015static struct microcode_ops microcode_intel_ops = {
1016 .request_microcode_user = request_microcode_user,
1017 .request_microcode_fw = request_microcode_fw,
1018 .collect_cpu_info = collect_cpu_info,
1019 .apply_microcode = apply_microcode_intel,
1020};
1021
1022static int __init calc_llc_size_per_core(struct cpuinfo_x86 *c)
1023{
1024 u64 llc_size = c->x86_cache_size * 1024ULL;
1025
1026 do_div(llc_size, c->x86_max_cores);
1027
1028 return (int)llc_size;
1029}
1030
1031struct microcode_ops * __init init_intel_microcode(void)
1032{
1033 struct cpuinfo_x86 *c = &boot_cpu_data;
1034
1035 if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
1036 cpu_has(c, X86_FEATURE_IA64)) {
1037 pr_err("Intel CPU family 0x%x not supported\n", c->x86);
1038 return NULL;
1039 }
1040
1041 llc_size_per_core = calc_llc_size_per_core(c);
1042
1043 return µcode_intel_ops;
1044}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Intel CPU Microcode Update Driver for Linux
4 *
5 * Copyright (C) 2000-2006 Tigran Aivazian <aivazian.tigran@gmail.com>
6 * 2006 Shaohua Li <shaohua.li@intel.com>
7 *
8 * Intel CPU microcode early update for Linux
9 *
10 * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
11 * H Peter Anvin" <hpa@zytor.com>
12 */
13#define pr_fmt(fmt) "microcode: " fmt
14#include <linux/earlycpio.h>
15#include <linux/firmware.h>
16#include <linux/uaccess.h>
17#include <linux/initrd.h>
18#include <linux/kernel.h>
19#include <linux/slab.h>
20#include <linux/cpu.h>
21#include <linux/uio.h>
22#include <linux/mm.h>
23
24#include <asm/intel-family.h>
25#include <asm/processor.h>
26#include <asm/tlbflush.h>
27#include <asm/setup.h>
28#include <asm/msr.h>
29
30#include "internal.h"
31
32static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
33
34#define UCODE_BSP_LOADED ((struct microcode_intel *)0x1UL)
35
36/* Current microcode patch used in early patching on the APs. */
37static struct microcode_intel *ucode_patch_va __read_mostly;
38static struct microcode_intel *ucode_patch_late __read_mostly;
39
40/* last level cache size per core */
41static unsigned int llc_size_per_core __ro_after_init;
42
43/* microcode format is extended from prescott processors */
44struct extended_signature {
45 unsigned int sig;
46 unsigned int pf;
47 unsigned int cksum;
48};
49
50struct extended_sigtable {
51 unsigned int count;
52 unsigned int cksum;
53 unsigned int reserved[3];
54 struct extended_signature sigs[];
55};
56
57#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
58#define EXT_HEADER_SIZE (sizeof(struct extended_sigtable))
59#define EXT_SIGNATURE_SIZE (sizeof(struct extended_signature))
60
61static inline unsigned int get_totalsize(struct microcode_header_intel *hdr)
62{
63 return hdr->datasize ? hdr->totalsize : DEFAULT_UCODE_TOTALSIZE;
64}
65
66static inline unsigned int exttable_size(struct extended_sigtable *et)
67{
68 return et->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE;
69}
70
71void intel_collect_cpu_info(struct cpu_signature *sig)
72{
73 sig->sig = cpuid_eax(1);
74 sig->pf = 0;
75 sig->rev = intel_get_microcode_revision();
76
77 if (x86_model(sig->sig) >= 5 || x86_family(sig->sig) > 6) {
78 unsigned int val[2];
79
80 /* get processor flags from MSR 0x17 */
81 native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
82 sig->pf = 1 << ((val[1] >> 18) & 7);
83 }
84}
85EXPORT_SYMBOL_GPL(intel_collect_cpu_info);
86
87static inline bool cpu_signatures_match(struct cpu_signature *s1, unsigned int sig2,
88 unsigned int pf2)
89{
90 if (s1->sig != sig2)
91 return false;
92
93 /* Processor flags are either both 0 or they intersect. */
94 return ((!s1->pf && !pf2) || (s1->pf & pf2));
95}
96
97bool intel_find_matching_signature(void *mc, struct cpu_signature *sig)
98{
99 struct microcode_header_intel *mc_hdr = mc;
100 struct extended_signature *ext_sig;
101 struct extended_sigtable *ext_hdr;
102 int i;
103
104 if (cpu_signatures_match(sig, mc_hdr->sig, mc_hdr->pf))
105 return true;
106
107 /* Look for ext. headers: */
108 if (get_totalsize(mc_hdr) <= intel_microcode_get_datasize(mc_hdr) + MC_HEADER_SIZE)
109 return false;
110
111 ext_hdr = mc + intel_microcode_get_datasize(mc_hdr) + MC_HEADER_SIZE;
112 ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE;
113
114 for (i = 0; i < ext_hdr->count; i++) {
115 if (cpu_signatures_match(sig, ext_sig->sig, ext_sig->pf))
116 return true;
117 ext_sig++;
118 }
119 return 0;
120}
121EXPORT_SYMBOL_GPL(intel_find_matching_signature);
122
123/**
124 * intel_microcode_sanity_check() - Sanity check microcode file.
125 * @mc: Pointer to the microcode file contents.
126 * @print_err: Display failure reason if true, silent if false.
127 * @hdr_type: Type of file, i.e. normal microcode file or In Field Scan file.
128 * Validate if the microcode header type matches with the type
129 * specified here.
130 *
131 * Validate certain header fields and verify if computed checksum matches
132 * with the one specified in the header.
133 *
134 * Return: 0 if the file passes all the checks, -EINVAL if any of the checks
135 * fail.
136 */
137int intel_microcode_sanity_check(void *mc, bool print_err, int hdr_type)
138{
139 unsigned long total_size, data_size, ext_table_size;
140 struct microcode_header_intel *mc_header = mc;
141 struct extended_sigtable *ext_header = NULL;
142 u32 sum, orig_sum, ext_sigcount = 0, i;
143 struct extended_signature *ext_sig;
144
145 total_size = get_totalsize(mc_header);
146 data_size = intel_microcode_get_datasize(mc_header);
147
148 if (data_size + MC_HEADER_SIZE > total_size) {
149 if (print_err)
150 pr_err("Error: bad microcode data file size.\n");
151 return -EINVAL;
152 }
153
154 if (mc_header->ldrver != 1 || mc_header->hdrver != hdr_type) {
155 if (print_err)
156 pr_err("Error: invalid/unknown microcode update format. Header type %d\n",
157 mc_header->hdrver);
158 return -EINVAL;
159 }
160
161 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
162 if (ext_table_size) {
163 u32 ext_table_sum = 0;
164 u32 *ext_tablep;
165
166 if (ext_table_size < EXT_HEADER_SIZE ||
167 ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
168 if (print_err)
169 pr_err("Error: truncated extended signature table.\n");
170 return -EINVAL;
171 }
172
173 ext_header = mc + MC_HEADER_SIZE + data_size;
174 if (ext_table_size != exttable_size(ext_header)) {
175 if (print_err)
176 pr_err("Error: extended signature table size mismatch.\n");
177 return -EFAULT;
178 }
179
180 ext_sigcount = ext_header->count;
181
182 /*
183 * Check extended table checksum: the sum of all dwords that
184 * comprise a valid table must be 0.
185 */
186 ext_tablep = (u32 *)ext_header;
187
188 i = ext_table_size / sizeof(u32);
189 while (i--)
190 ext_table_sum += ext_tablep[i];
191
192 if (ext_table_sum) {
193 if (print_err)
194 pr_warn("Bad extended signature table checksum, aborting.\n");
195 return -EINVAL;
196 }
197 }
198
199 /*
200 * Calculate the checksum of update data and header. The checksum of
201 * valid update data and header including the extended signature table
202 * must be 0.
203 */
204 orig_sum = 0;
205 i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
206 while (i--)
207 orig_sum += ((u32 *)mc)[i];
208
209 if (orig_sum) {
210 if (print_err)
211 pr_err("Bad microcode data checksum, aborting.\n");
212 return -EINVAL;
213 }
214
215 if (!ext_table_size)
216 return 0;
217
218 /*
219 * Check extended signature checksum: 0 => valid.
220 */
221 for (i = 0; i < ext_sigcount; i++) {
222 ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
223 EXT_SIGNATURE_SIZE * i;
224
225 sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
226 (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
227 if (sum) {
228 if (print_err)
229 pr_err("Bad extended signature checksum, aborting.\n");
230 return -EINVAL;
231 }
232 }
233 return 0;
234}
235EXPORT_SYMBOL_GPL(intel_microcode_sanity_check);
236
237static void update_ucode_pointer(struct microcode_intel *mc)
238{
239 kvfree(ucode_patch_va);
240
241 /*
242 * Save the virtual address for early loading and for eventual free
243 * on late loading.
244 */
245 ucode_patch_va = mc;
246}
247
248static void save_microcode_patch(struct microcode_intel *patch)
249{
250 unsigned int size = get_totalsize(&patch->hdr);
251 struct microcode_intel *mc;
252
253 mc = kvmemdup(patch, size, GFP_KERNEL);
254 if (mc)
255 update_ucode_pointer(mc);
256 else
257 pr_err("Unable to allocate microcode memory size: %u\n", size);
258}
259
260/* Scan blob for microcode matching the boot CPUs family, model, stepping */
261static __init struct microcode_intel *scan_microcode(void *data, size_t size,
262 struct ucode_cpu_info *uci,
263 bool save)
264{
265 struct microcode_header_intel *mc_header;
266 struct microcode_intel *patch = NULL;
267 u32 cur_rev = uci->cpu_sig.rev;
268 unsigned int mc_size;
269
270 for (; size >= sizeof(struct microcode_header_intel); size -= mc_size, data += mc_size) {
271 mc_header = (struct microcode_header_intel *)data;
272
273 mc_size = get_totalsize(mc_header);
274 if (!mc_size || mc_size > size ||
275 intel_microcode_sanity_check(data, false, MC_HEADER_TYPE_MICROCODE) < 0)
276 break;
277
278 if (!intel_find_matching_signature(data, &uci->cpu_sig))
279 continue;
280
281 /*
282 * For saving the early microcode, find the matching revision which
283 * was loaded on the BSP.
284 *
285 * On the BSP during early boot, find a newer revision than
286 * actually loaded in the CPU.
287 */
288 if (save) {
289 if (cur_rev != mc_header->rev)
290 continue;
291 } else if (cur_rev >= mc_header->rev) {
292 continue;
293 }
294
295 patch = data;
296 cur_rev = mc_header->rev;
297 }
298
299 return size ? NULL : patch;
300}
301
302static enum ucode_state __apply_microcode(struct ucode_cpu_info *uci,
303 struct microcode_intel *mc,
304 u32 *cur_rev)
305{
306 u32 rev;
307
308 if (!mc)
309 return UCODE_NFOUND;
310
311 /*
312 * Save us the MSR write below - which is a particular expensive
313 * operation - when the other hyperthread has updated the microcode
314 * already.
315 */
316 *cur_rev = intel_get_microcode_revision();
317 if (*cur_rev >= mc->hdr.rev) {
318 uci->cpu_sig.rev = *cur_rev;
319 return UCODE_OK;
320 }
321
322 /*
323 * Writeback and invalidate caches before updating microcode to avoid
324 * internal issues depending on what the microcode is updating.
325 */
326 native_wbinvd();
327
328 /* write microcode via MSR 0x79 */
329 native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
330
331 rev = intel_get_microcode_revision();
332 if (rev != mc->hdr.rev)
333 return UCODE_ERROR;
334
335 uci->cpu_sig.rev = rev;
336 return UCODE_UPDATED;
337}
338
339static enum ucode_state apply_microcode_early(struct ucode_cpu_info *uci)
340{
341 struct microcode_intel *mc = uci->mc;
342 u32 cur_rev;
343
344 return __apply_microcode(uci, mc, &cur_rev);
345}
346
347static __init bool load_builtin_intel_microcode(struct cpio_data *cp)
348{
349 unsigned int eax = 1, ebx, ecx = 0, edx;
350 struct firmware fw;
351 char name[30];
352
353 if (IS_ENABLED(CONFIG_X86_32))
354 return false;
355
356 native_cpuid(&eax, &ebx, &ecx, &edx);
357
358 sprintf(name, "intel-ucode/%02x-%02x-%02x",
359 x86_family(eax), x86_model(eax), x86_stepping(eax));
360
361 if (firmware_request_builtin(&fw, name)) {
362 cp->size = fw.size;
363 cp->data = (void *)fw.data;
364 return true;
365 }
366 return false;
367}
368
369static __init struct microcode_intel *get_microcode_blob(struct ucode_cpu_info *uci, bool save)
370{
371 struct cpio_data cp;
372
373 intel_collect_cpu_info(&uci->cpu_sig);
374
375 if (!load_builtin_intel_microcode(&cp))
376 cp = find_microcode_in_initrd(ucode_path);
377
378 if (!(cp.data && cp.size))
379 return NULL;
380
381 return scan_microcode(cp.data, cp.size, uci, save);
382}
383
384/*
385 * Invoked from an early init call to save the microcode blob which was
386 * selected during early boot when mm was not usable. The microcode must be
387 * saved because initrd is going away. It's an early init call so the APs
388 * just can use the pointer and do not have to scan initrd/builtin firmware
389 * again.
390 */
391static int __init save_builtin_microcode(void)
392{
393 struct ucode_cpu_info uci;
394
395 if (xchg(&ucode_patch_va, NULL) != UCODE_BSP_LOADED)
396 return 0;
397
398 if (dis_ucode_ldr || boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
399 return 0;
400
401 uci.mc = get_microcode_blob(&uci, true);
402 if (uci.mc)
403 save_microcode_patch(uci.mc);
404 return 0;
405}
406early_initcall(save_builtin_microcode);
407
408/* Load microcode on BSP from initrd or builtin blobs */
409void __init load_ucode_intel_bsp(struct early_load_data *ed)
410{
411 struct ucode_cpu_info uci;
412
413 uci.mc = get_microcode_blob(&uci, false);
414 ed->old_rev = uci.cpu_sig.rev;
415
416 if (uci.mc && apply_microcode_early(&uci) == UCODE_UPDATED) {
417 ucode_patch_va = UCODE_BSP_LOADED;
418 ed->new_rev = uci.cpu_sig.rev;
419 }
420}
421
422void load_ucode_intel_ap(void)
423{
424 struct ucode_cpu_info uci;
425
426 uci.mc = ucode_patch_va;
427 if (uci.mc)
428 apply_microcode_early(&uci);
429}
430
431/* Reload microcode on resume */
432void reload_ucode_intel(void)
433{
434 struct ucode_cpu_info uci = { .mc = ucode_patch_va, };
435
436 if (uci.mc)
437 apply_microcode_early(&uci);
438}
439
440static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
441{
442 intel_collect_cpu_info(csig);
443 return 0;
444}
445
446static enum ucode_state apply_microcode_late(int cpu)
447{
448 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
449 struct microcode_intel *mc = ucode_patch_late;
450 enum ucode_state ret;
451 u32 cur_rev;
452
453 if (WARN_ON_ONCE(smp_processor_id() != cpu))
454 return UCODE_ERROR;
455
456 ret = __apply_microcode(uci, mc, &cur_rev);
457 if (ret != UCODE_UPDATED && ret != UCODE_OK)
458 return ret;
459
460 cpu_data(cpu).microcode = uci->cpu_sig.rev;
461 if (!cpu)
462 boot_cpu_data.microcode = uci->cpu_sig.rev;
463
464 return ret;
465}
466
467static bool ucode_validate_minrev(struct microcode_header_intel *mc_header)
468{
469 int cur_rev = boot_cpu_data.microcode;
470
471 /*
472 * When late-loading, ensure the header declares a minimum revision
473 * required to perform a late-load. The previously reserved field
474 * is 0 in older microcode blobs.
475 */
476 if (!mc_header->min_req_ver) {
477 pr_info("Unsafe microcode update: Microcode header does not specify a required min version\n");
478 return false;
479 }
480
481 /*
482 * Check whether the current revision is either greater or equal to
483 * to the minimum revision specified in the header.
484 */
485 if (cur_rev < mc_header->min_req_ver) {
486 pr_info("Unsafe microcode update: Current revision 0x%x too old\n", cur_rev);
487 pr_info("Current should be at 0x%x or higher. Use early loading instead\n", mc_header->min_req_ver);
488 return false;
489 }
490 return true;
491}
492
493static enum ucode_state parse_microcode_blobs(int cpu, struct iov_iter *iter)
494{
495 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
496 bool is_safe, new_is_safe = false;
497 int cur_rev = uci->cpu_sig.rev;
498 unsigned int curr_mc_size = 0;
499 u8 *new_mc = NULL, *mc = NULL;
500
501 while (iov_iter_count(iter)) {
502 struct microcode_header_intel mc_header;
503 unsigned int mc_size, data_size;
504 u8 *data;
505
506 if (!copy_from_iter_full(&mc_header, sizeof(mc_header), iter)) {
507 pr_err("error! Truncated or inaccessible header in microcode data file\n");
508 goto fail;
509 }
510
511 mc_size = get_totalsize(&mc_header);
512 if (mc_size < sizeof(mc_header)) {
513 pr_err("error! Bad data in microcode data file (totalsize too small)\n");
514 goto fail;
515 }
516 data_size = mc_size - sizeof(mc_header);
517 if (data_size > iov_iter_count(iter)) {
518 pr_err("error! Bad data in microcode data file (truncated file?)\n");
519 goto fail;
520 }
521
522 /* For performance reasons, reuse mc area when possible */
523 if (!mc || mc_size > curr_mc_size) {
524 kvfree(mc);
525 mc = kvmalloc(mc_size, GFP_KERNEL);
526 if (!mc)
527 goto fail;
528 curr_mc_size = mc_size;
529 }
530
531 memcpy(mc, &mc_header, sizeof(mc_header));
532 data = mc + sizeof(mc_header);
533 if (!copy_from_iter_full(data, data_size, iter) ||
534 intel_microcode_sanity_check(mc, true, MC_HEADER_TYPE_MICROCODE) < 0)
535 goto fail;
536
537 if (cur_rev >= mc_header.rev)
538 continue;
539
540 if (!intel_find_matching_signature(mc, &uci->cpu_sig))
541 continue;
542
543 is_safe = ucode_validate_minrev(&mc_header);
544 if (force_minrev && !is_safe)
545 continue;
546
547 kvfree(new_mc);
548 cur_rev = mc_header.rev;
549 new_mc = mc;
550 new_is_safe = is_safe;
551 mc = NULL;
552 }
553
554 if (iov_iter_count(iter))
555 goto fail;
556
557 kvfree(mc);
558 if (!new_mc)
559 return UCODE_NFOUND;
560
561 ucode_patch_late = (struct microcode_intel *)new_mc;
562 return new_is_safe ? UCODE_NEW_SAFE : UCODE_NEW;
563
564fail:
565 kvfree(mc);
566 kvfree(new_mc);
567 return UCODE_ERROR;
568}
569
570static bool is_blacklisted(unsigned int cpu)
571{
572 struct cpuinfo_x86 *c = &cpu_data(cpu);
573
574 /*
575 * Late loading on model 79 with microcode revision less than 0x0b000021
576 * and LLC size per core bigger than 2.5MB may result in a system hang.
577 * This behavior is documented in item BDF90, #334165 (Intel Xeon
578 * Processor E7-8800/4800 v4 Product Family).
579 */
580 if (c->x86 == 6 &&
581 c->x86_model == INTEL_FAM6_BROADWELL_X &&
582 c->x86_stepping == 0x01 &&
583 llc_size_per_core > 2621440 &&
584 c->microcode < 0x0b000021) {
585 pr_err_once("Erratum BDF90: late loading with revision < 0x0b000021 (0x%x) disabled.\n", c->microcode);
586 pr_err_once("Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
587 return true;
588 }
589
590 return false;
591}
592
593static enum ucode_state request_microcode_fw(int cpu, struct device *device)
594{
595 struct cpuinfo_x86 *c = &cpu_data(cpu);
596 const struct firmware *firmware;
597 struct iov_iter iter;
598 enum ucode_state ret;
599 struct kvec kvec;
600 char name[30];
601
602 if (is_blacklisted(cpu))
603 return UCODE_NFOUND;
604
605 sprintf(name, "intel-ucode/%02x-%02x-%02x",
606 c->x86, c->x86_model, c->x86_stepping);
607
608 if (request_firmware_direct(&firmware, name, device)) {
609 pr_debug("data file %s load failed\n", name);
610 return UCODE_NFOUND;
611 }
612
613 kvec.iov_base = (void *)firmware->data;
614 kvec.iov_len = firmware->size;
615 iov_iter_kvec(&iter, ITER_SOURCE, &kvec, 1, firmware->size);
616 ret = parse_microcode_blobs(cpu, &iter);
617
618 release_firmware(firmware);
619
620 return ret;
621}
622
623static void finalize_late_load(int result)
624{
625 if (!result)
626 update_ucode_pointer(ucode_patch_late);
627 else
628 kvfree(ucode_patch_late);
629 ucode_patch_late = NULL;
630}
631
632static struct microcode_ops microcode_intel_ops = {
633 .request_microcode_fw = request_microcode_fw,
634 .collect_cpu_info = collect_cpu_info,
635 .apply_microcode = apply_microcode_late,
636 .finalize_late_load = finalize_late_load,
637 .use_nmi = IS_ENABLED(CONFIG_X86_64),
638};
639
640static __init void calc_llc_size_per_core(struct cpuinfo_x86 *c)
641{
642 u64 llc_size = c->x86_cache_size * 1024ULL;
643
644 do_div(llc_size, c->x86_max_cores);
645 llc_size_per_core = (unsigned int)llc_size;
646}
647
648struct microcode_ops * __init init_intel_microcode(void)
649{
650 struct cpuinfo_x86 *c = &boot_cpu_data;
651
652 if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
653 cpu_has(c, X86_FEATURE_IA64)) {
654 pr_err("Intel CPU family 0x%x not supported\n", c->x86);
655 return NULL;
656 }
657
658 calc_llc_size_per_core(c);
659
660 return µcode_intel_ops;
661}