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9#include <linux/capability.h>
10#include <linux/mm.h>
11#include <linux/file.h>
12#include <linux/slab.h>
13#include <linux/fs.h>
14#include <linux/kexec.h>
15#include <linux/mutex.h>
16#include <linux/list.h>
17#include <linux/highmem.h>
18#include <linux/syscalls.h>
19#include <linux/reboot.h>
20#include <linux/ioport.h>
21#include <linux/hardirq.h>
22#include <linux/elf.h>
23#include <linux/elfcore.h>
24#include <linux/utsrelease.h>
25#include <linux/utsname.h>
26#include <linux/numa.h>
27#include <linux/suspend.h>
28#include <linux/device.h>
29#include <linux/freezer.h>
30#include <linux/pm.h>
31#include <linux/cpu.h>
32#include <linux/console.h>
33#include <linux/vmalloc.h>
34
35#include <asm/page.h>
36#include <asm/uaccess.h>
37#include <asm/io.h>
38#include <asm/system.h>
39#include <asm/sections.h>
40
41
42note_buf_t* crash_notes;
43
44
45static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
46u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
47size_t vmcoreinfo_size;
48size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);
49
50
51struct resource crashk_res = {
52 .name = "Crash kernel",
53 .start = 0,
54 .end = 0,
55 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
56};
57
58int kexec_should_crash(struct task_struct *p)
59{
60 if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
61 return 1;
62 return 0;
63}
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108
109#define KIMAGE_NO_DEST (-1UL)
110
111static int kimage_is_destination_range(struct kimage *image,
112 unsigned long start, unsigned long end);
113static struct page *kimage_alloc_page(struct kimage *image,
114 gfp_t gfp_mask,
115 unsigned long dest);
116
117static int do_kimage_alloc(struct kimage **rimage, unsigned long entry,
118 unsigned long nr_segments,
119 struct kexec_segment __user *segments)
120{
121 size_t segment_bytes;
122 struct kimage *image;
123 unsigned long i;
124 int result;
125
126
127 result = -ENOMEM;
128 image = kzalloc(sizeof(*image), GFP_KERNEL);
129 if (!image)
130 goto out;
131
132 image->head = 0;
133 image->entry = &image->head;
134 image->last_entry = &image->head;
135 image->control_page = ~0;
136 image->start = entry;
137 image->type = KEXEC_TYPE_DEFAULT;
138
139
140 INIT_LIST_HEAD(&image->control_pages);
141
142
143 INIT_LIST_HEAD(&image->dest_pages);
144
145
146 INIT_LIST_HEAD(&image->unuseable_pages);
147
148
149 image->nr_segments = nr_segments;
150 segment_bytes = nr_segments * sizeof(*segments);
151 result = copy_from_user(image->segment, segments, segment_bytes);
152 if (result)
153 goto out;
154
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165
166
167
168 result = -EADDRNOTAVAIL;
169 for (i = 0; i < nr_segments; i++) {
170 unsigned long mstart, mend;
171
172 mstart = image->segment[i].mem;
173 mend = mstart + image->segment[i].memsz;
174 if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK))
175 goto out;
176 if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT)
177 goto out;
178 }
179
180
181
182
183
184
185 result = -EINVAL;
186 for (i = 0; i < nr_segments; i++) {
187 unsigned long mstart, mend;
188 unsigned long j;
189
190 mstart = image->segment[i].mem;
191 mend = mstart + image->segment[i].memsz;
192 for (j = 0; j < i; j++) {
193 unsigned long pstart, pend;
194 pstart = image->segment[j].mem;
195 pend = pstart + image->segment[j].memsz;
196
197 if ((mend > pstart) && (mstart < pend))
198 goto out;
199 }
200 }
201
202
203
204
205
206
207 result = -EINVAL;
208 for (i = 0; i < nr_segments; i++) {
209 if (image->segment[i].bufsz > image->segment[i].memsz)
210 goto out;
211 }
212
213 result = 0;
214out:
215 if (result == 0)
216 *rimage = image;
217 else
218 kfree(image);
219
220 return result;
221
222}
223
224static int kimage_normal_alloc(struct kimage **rimage, unsigned long entry,
225 unsigned long nr_segments,
226 struct kexec_segment __user *segments)
227{
228 int result;
229 struct kimage *image;
230
231
232 image = NULL;
233 result = do_kimage_alloc(&image, entry, nr_segments, segments);
234 if (result)
235 goto out;
236
237 *rimage = image;
238
239
240
241
242
243
244 result = -ENOMEM;
245 image->control_code_page = kimage_alloc_control_pages(image,
246 get_order(KEXEC_CONTROL_PAGE_SIZE));
247 if (!image->control_code_page) {
248 printk(KERN_ERR "Could not allocate control_code_buffer\n");
249 goto out;
250 }
251
252 image->swap_page = kimage_alloc_control_pages(image, 0);
253 if (!image->swap_page) {
254 printk(KERN_ERR "Could not allocate swap buffer\n");
255 goto out;
256 }
257
258 result = 0;
259 out:
260 if (result == 0)
261 *rimage = image;
262 else
263 kfree(image);
264
265 return result;
266}
267
268static int kimage_crash_alloc(struct kimage **rimage, unsigned long entry,
269 unsigned long nr_segments,
270 struct kexec_segment __user *segments)
271{
272 int result;
273 struct kimage *image;
274 unsigned long i;
275
276 image = NULL;
277
278 if ((entry < crashk_res.start) || (entry > crashk_res.end)) {
279 result = -EADDRNOTAVAIL;
280 goto out;
281 }
282
283
284 result = do_kimage_alloc(&image, entry, nr_segments, segments);
285 if (result)
286 goto out;
287
288
289
290
291 image->control_page = crashk_res.start;
292 image->type = KEXEC_TYPE_CRASH;
293
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300
301
302
303 result = -EADDRNOTAVAIL;
304 for (i = 0; i < nr_segments; i++) {
305 unsigned long mstart, mend;
306
307 mstart = image->segment[i].mem;
308 mend = mstart + image->segment[i].memsz - 1;
309
310 if ((mstart < crashk_res.start) || (mend > crashk_res.end))
311 goto out;
312 }
313
314
315
316
317
318
319 result = -ENOMEM;
320 image->control_code_page = kimage_alloc_control_pages(image,
321 get_order(KEXEC_CONTROL_PAGE_SIZE));
322 if (!image->control_code_page) {
323 printk(KERN_ERR "Could not allocate control_code_buffer\n");
324 goto out;
325 }
326
327 result = 0;
328out:
329 if (result == 0)
330 *rimage = image;
331 else
332 kfree(image);
333
334 return result;
335}
336
337static int kimage_is_destination_range(struct kimage *image,
338 unsigned long start,
339 unsigned long end)
340{
341 unsigned long i;
342
343 for (i = 0; i < image->nr_segments; i++) {
344 unsigned long mstart, mend;
345
346 mstart = image->segment[i].mem;
347 mend = mstart + image->segment[i].memsz;
348 if ((end > mstart) && (start < mend))
349 return 1;
350 }
351
352 return 0;
353}
354
355static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order)
356{
357 struct page *pages;
358
359 pages = alloc_pages(gfp_mask, order);
360 if (pages) {
361 unsigned int count, i;
362 pages->mapping = NULL;
363 set_page_private(pages, order);
364 count = 1 << order;
365 for (i = 0; i < count; i++)
366 SetPageReserved(pages + i);
367 }
368
369 return pages;
370}
371
372static void kimage_free_pages(struct page *page)
373{
374 unsigned int order, count, i;
375
376 order = page_private(page);
377 count = 1 << order;
378 for (i = 0; i < count; i++)
379 ClearPageReserved(page + i);
380 __free_pages(page, order);
381}
382
383static void kimage_free_page_list(struct list_head *list)
384{
385 struct list_head *pos, *next;
386
387 list_for_each_safe(pos, next, list) {
388 struct page *page;
389
390 page = list_entry(pos, struct page, lru);
391 list_del(&page->lru);
392 kimage_free_pages(page);
393 }
394}
395
396static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
397 unsigned int order)
398{
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410
411
412 struct list_head extra_pages;
413 struct page *pages;
414 unsigned int count;
415
416 count = 1 << order;
417 INIT_LIST_HEAD(&extra_pages);
418
419
420
421
422 do {
423 unsigned long pfn, epfn, addr, eaddr;
424
425 pages = kimage_alloc_pages(GFP_KERNEL, order);
426 if (!pages)
427 break;
428 pfn = page_to_pfn(pages);
429 epfn = pfn + count;
430 addr = pfn << PAGE_SHIFT;
431 eaddr = epfn << PAGE_SHIFT;
432 if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
433 kimage_is_destination_range(image, addr, eaddr)) {
434 list_add(&pages->lru, &extra_pages);
435 pages = NULL;
436 }
437 } while (!pages);
438
439 if (pages) {
440
441 list_add(&pages->lru, &image->control_pages);
442
443
444
445
446
447
448
449 }
450
451
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455
456
457 kimage_free_page_list(&extra_pages);
458
459 return pages;
460}
461
462static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
463 unsigned int order)
464{
465
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484
485
486 unsigned long hole_start, hole_end, size;
487 struct page *pages;
488
489 pages = NULL;
490 size = (1 << order) << PAGE_SHIFT;
491 hole_start = (image->control_page + (size - 1)) & ~(size - 1);
492 hole_end = hole_start + size - 1;
493 while (hole_end <= crashk_res.end) {
494 unsigned long i;
495
496 if (hole_end > KEXEC_CONTROL_MEMORY_LIMIT)
497 break;
498 if (hole_end > crashk_res.end)
499 break;
500
501 for (i = 0; i < image->nr_segments; i++) {
502 unsigned long mstart, mend;
503
504 mstart = image->segment[i].mem;
505 mend = mstart + image->segment[i].memsz - 1;
506 if ((hole_end >= mstart) && (hole_start <= mend)) {
507
508 hole_start = (mend + (size - 1)) & ~(size - 1);
509 hole_end = hole_start + size - 1;
510 break;
511 }
512 }
513
514 if (i == image->nr_segments) {
515 pages = pfn_to_page(hole_start >> PAGE_SHIFT);
516 break;
517 }
518 }
519 if (pages)
520 image->control_page = hole_end;
521
522 return pages;
523}
524
525
526struct page *kimage_alloc_control_pages(struct kimage *image,
527 unsigned int order)
528{
529 struct page *pages = NULL;
530
531 switch (image->type) {
532 case KEXEC_TYPE_DEFAULT:
533 pages = kimage_alloc_normal_control_pages(image, order);
534 break;
535 case KEXEC_TYPE_CRASH:
536 pages = kimage_alloc_crash_control_pages(image, order);
537 break;
538 }
539
540 return pages;
541}
542
543static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
544{
545 if (*image->entry != 0)
546 image->entry++;
547
548 if (image->entry == image->last_entry) {
549 kimage_entry_t *ind_page;
550 struct page *page;
551
552 page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST);
553 if (!page)
554 return -ENOMEM;
555
556 ind_page = page_address(page);
557 *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
558 image->entry = ind_page;
559 image->last_entry = ind_page +
560 ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
561 }
562 *image->entry = entry;
563 image->entry++;
564 *image->entry = 0;
565
566 return 0;
567}
568
569static int kimage_set_destination(struct kimage *image,
570 unsigned long destination)
571{
572 int result;
573
574 destination &= PAGE_MASK;
575 result = kimage_add_entry(image, destination | IND_DESTINATION);
576 if (result == 0)
577 image->destination = destination;
578
579 return result;
580}
581
582
583static int kimage_add_page(struct kimage *image, unsigned long page)
584{
585 int result;
586
587 page &= PAGE_MASK;
588 result = kimage_add_entry(image, page | IND_SOURCE);
589 if (result == 0)
590 image->destination += PAGE_SIZE;
591
592 return result;
593}
594
595
596static void kimage_free_extra_pages(struct kimage *image)
597{
598
599 kimage_free_page_list(&image->dest_pages);
600
601
602 kimage_free_page_list(&image->unuseable_pages);
603
604}
605static void kimage_terminate(struct kimage *image)
606{
607 if (*image->entry != 0)
608 image->entry++;
609
610 *image->entry = IND_DONE;
611}
612
613#define for_each_kimage_entry(image, ptr, entry) \
614 for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \
615 ptr = (entry & IND_INDIRECTION)? \
616 phys_to_virt((entry & PAGE_MASK)): ptr +1)
617
618static void kimage_free_entry(kimage_entry_t entry)
619{
620 struct page *page;
621
622 page = pfn_to_page(entry >> PAGE_SHIFT);
623 kimage_free_pages(page);
624}
625
626static void kimage_free(struct kimage *image)
627{
628 kimage_entry_t *ptr, entry;
629 kimage_entry_t ind = 0;
630
631 if (!image)
632 return;
633
634 kimage_free_extra_pages(image);
635 for_each_kimage_entry(image, ptr, entry) {
636 if (entry & IND_INDIRECTION) {
637
638 if (ind & IND_INDIRECTION)
639 kimage_free_entry(ind);
640
641
642
643 ind = entry;
644 }
645 else if (entry & IND_SOURCE)
646 kimage_free_entry(entry);
647 }
648
649 if (ind & IND_INDIRECTION)
650 kimage_free_entry(ind);
651
652
653 machine_kexec_cleanup(image);
654
655
656 kimage_free_page_list(&image->control_pages);
657 kfree(image);
658}
659
660static kimage_entry_t *kimage_dst_used(struct kimage *image,
661 unsigned long page)
662{
663 kimage_entry_t *ptr, entry;
664 unsigned long destination = 0;
665
666 for_each_kimage_entry(image, ptr, entry) {
667 if (entry & IND_DESTINATION)
668 destination = entry & PAGE_MASK;
669 else if (entry & IND_SOURCE) {
670 if (page == destination)
671 return ptr;
672 destination += PAGE_SIZE;
673 }
674 }
675
676 return NULL;
677}
678
679static struct page *kimage_alloc_page(struct kimage *image,
680 gfp_t gfp_mask,
681 unsigned long destination)
682{
683
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699
700
701 struct page *page;
702 unsigned long addr;
703
704
705
706
707
708 list_for_each_entry(page, &image->dest_pages, lru) {
709 addr = page_to_pfn(page) << PAGE_SHIFT;
710 if (addr == destination) {
711 list_del(&page->lru);
712 return page;
713 }
714 }
715 page = NULL;
716 while (1) {
717 kimage_entry_t *old;
718
719
720 page = kimage_alloc_pages(gfp_mask, 0);
721 if (!page)
722 return NULL;
723
724 if (page_to_pfn(page) >
725 (KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) {
726 list_add(&page->lru, &image->unuseable_pages);
727 continue;
728 }
729 addr = page_to_pfn(page) << PAGE_SHIFT;
730
731
732 if (addr == destination)
733 break;
734
735
736 if (!kimage_is_destination_range(image, addr,
737 addr + PAGE_SIZE))
738 break;
739
740
741
742
743
744
745 old = kimage_dst_used(image, addr);
746 if (old) {
747
748 unsigned long old_addr;
749 struct page *old_page;
750
751 old_addr = *old & PAGE_MASK;
752 old_page = pfn_to_page(old_addr >> PAGE_SHIFT);
753 copy_highpage(page, old_page);
754 *old = addr | (*old & ~PAGE_MASK);
755
756
757
758
759
760 if (!(gfp_mask & __GFP_HIGHMEM) &&
761 PageHighMem(old_page)) {
762 kimage_free_pages(old_page);
763 continue;
764 }
765 addr = old_addr;
766 page = old_page;
767 break;
768 }
769 else {
770
771
772
773 list_add(&page->lru, &image->dest_pages);
774 }
775 }
776
777 return page;
778}
779
780static int kimage_load_normal_segment(struct kimage *image,
781 struct kexec_segment *segment)
782{
783 unsigned long maddr;
784 unsigned long ubytes, mbytes;
785 int result;
786 unsigned char __user *buf;
787
788 result = 0;
789 buf = segment->buf;
790 ubytes = segment->bufsz;
791 mbytes = segment->memsz;
792 maddr = segment->mem;
793
794 result = kimage_set_destination(image, maddr);
795 if (result < 0)
796 goto out;
797
798 while (mbytes) {
799 struct page *page;
800 char *ptr;
801 size_t uchunk, mchunk;
802
803 page = kimage_alloc_page(image, GFP_HIGHUSER, maddr);
804 if (!page) {
805 result = -ENOMEM;
806 goto out;
807 }
808 result = kimage_add_page(image, page_to_pfn(page)
809 << PAGE_SHIFT);
810 if (result < 0)
811 goto out;
812
813 ptr = kmap(page);
814
815 memset(ptr, 0, PAGE_SIZE);
816 ptr += maddr & ~PAGE_MASK;
817 mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK);
818 if (mchunk > mbytes)
819 mchunk = mbytes;
820
821 uchunk = mchunk;
822 if (uchunk > ubytes)
823 uchunk = ubytes;
824
825 result = copy_from_user(ptr, buf, uchunk);
826 kunmap(page);
827 if (result) {
828 result = (result < 0) ? result : -EIO;
829 goto out;
830 }
831 ubytes -= uchunk;
832 maddr += mchunk;
833 buf += mchunk;
834 mbytes -= mchunk;
835 }
836out:
837 return result;
838}
839
840static int kimage_load_crash_segment(struct kimage *image,
841 struct kexec_segment *segment)
842{
843
844
845
846
847 unsigned long maddr;
848 unsigned long ubytes, mbytes;
849 int result;
850 unsigned char __user *buf;
851
852 result = 0;
853 buf = segment->buf;
854 ubytes = segment->bufsz;
855 mbytes = segment->memsz;
856 maddr = segment->mem;
857 while (mbytes) {
858 struct page *page;
859 char *ptr;
860 size_t uchunk, mchunk;
861
862 page = pfn_to_page(maddr >> PAGE_SHIFT);
863 if (!page) {
864 result = -ENOMEM;
865 goto out;
866 }
867 ptr = kmap(page);
868 ptr += maddr & ~PAGE_MASK;
869 mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK);
870 if (mchunk > mbytes)
871 mchunk = mbytes;
872
873 uchunk = mchunk;
874 if (uchunk > ubytes) {
875 uchunk = ubytes;
876
877 memset(ptr + uchunk, 0, mchunk - uchunk);
878 }
879 result = copy_from_user(ptr, buf, uchunk);
880 kexec_flush_icache_page(page);
881 kunmap(page);
882 if (result) {
883 result = (result < 0) ? result : -EIO;
884 goto out;
885 }
886 ubytes -= uchunk;
887 maddr += mchunk;
888 buf += mchunk;
889 mbytes -= mchunk;
890 }
891out:
892 return result;
893}
894
895static int kimage_load_segment(struct kimage *image,
896 struct kexec_segment *segment)
897{
898 int result = -ENOMEM;
899
900 switch (image->type) {
901 case KEXEC_TYPE_DEFAULT:
902 result = kimage_load_normal_segment(image, segment);
903 break;
904 case KEXEC_TYPE_CRASH:
905 result = kimage_load_crash_segment(image, segment);
906 break;
907 }
908
909 return result;
910}
911
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931
932struct kimage *kexec_image;
933struct kimage *kexec_crash_image;
934
935static DEFINE_MUTEX(kexec_mutex);
936
937SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
938 struct kexec_segment __user *, segments, unsigned long, flags)
939{
940 struct kimage **dest_image, *image;
941 int result;
942
943
944 if (!capable(CAP_SYS_BOOT))
945 return -EPERM;
946
947
948
949
950
951 if ((flags & KEXEC_FLAGS) != (flags & ~KEXEC_ARCH_MASK))
952 return -EINVAL;
953
954
955 if (((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH) &&
956 ((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT))
957 return -EINVAL;
958
959
960
961
962 if (nr_segments > KEXEC_SEGMENT_MAX)
963 return -EINVAL;
964
965 image = NULL;
966 result = 0;
967
968
969
970
971
972
973
974
975
976 if (!mutex_trylock(&kexec_mutex))
977 return -EBUSY;
978
979 dest_image = &kexec_image;
980 if (flags & KEXEC_ON_CRASH)
981 dest_image = &kexec_crash_image;
982 if (nr_segments > 0) {
983 unsigned long i;
984
985
986 if ((flags & KEXEC_ON_CRASH) == 0)
987 result = kimage_normal_alloc(&image, entry,
988 nr_segments, segments);
989
990 else if (flags & KEXEC_ON_CRASH) {
991
992
993
994 kimage_free(xchg(&kexec_crash_image, NULL));
995 result = kimage_crash_alloc(&image, entry,
996 nr_segments, segments);
997 }
998 if (result)
999 goto out;
1000
1001 if (flags & KEXEC_PRESERVE_CONTEXT)
1002 image->preserve_context = 1;
1003 result = machine_kexec_prepare(image);
1004 if (result)
1005 goto out;
1006
1007 for (i = 0; i < nr_segments; i++) {
1008 result = kimage_load_segment(image, &image->segment[i]);
1009 if (result)
1010 goto out;
1011 }
1012 kimage_terminate(image);
1013 }
1014
1015 image = xchg(dest_image, image);
1016
1017out:
1018 mutex_unlock(&kexec_mutex);
1019 kimage_free(image);
1020
1021 return result;
1022}
1023
1024#ifdef CONFIG_COMPAT
1025asmlinkage long compat_sys_kexec_load(unsigned long entry,
1026 unsigned long nr_segments,
1027 struct compat_kexec_segment __user *segments,
1028 unsigned long flags)
1029{
1030 struct compat_kexec_segment in;
1031 struct kexec_segment out, __user *ksegments;
1032 unsigned long i, result;
1033
1034
1035
1036
1037 if ((flags & KEXEC_ARCH_MASK) == KEXEC_ARCH_DEFAULT)
1038 return -EINVAL;
1039
1040 if (nr_segments > KEXEC_SEGMENT_MAX)
1041 return -EINVAL;
1042
1043 ksegments = compat_alloc_user_space(nr_segments * sizeof(out));
1044 for (i=0; i < nr_segments; i++) {
1045 result = copy_from_user(&in, &segments[i], sizeof(in));
1046 if (result)
1047 return -EFAULT;
1048
1049 out.buf = compat_ptr(in.buf);
1050 out.bufsz = in.bufsz;
1051 out.mem = in.mem;
1052 out.memsz = in.memsz;
1053
1054 result = copy_to_user(&ksegments[i], &out, sizeof(out));
1055 if (result)
1056 return -EFAULT;
1057 }
1058
1059 return sys_kexec_load(entry, nr_segments, ksegments, flags);
1060}
1061#endif
1062
1063void crash_kexec(struct pt_regs *regs)
1064{
1065
1066
1067
1068
1069
1070
1071
1072
1073 if (mutex_trylock(&kexec_mutex)) {
1074 if (kexec_crash_image) {
1075 struct pt_regs fixed_regs;
1076 crash_setup_regs(&fixed_regs, regs);
1077 crash_save_vmcoreinfo();
1078 machine_crash_shutdown(&fixed_regs);
1079 machine_kexec(kexec_crash_image);
1080 }
1081 mutex_unlock(&kexec_mutex);
1082 }
1083}
1084
1085static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
1086 size_t data_len)
1087{
1088 struct elf_note note;
1089
1090 note.n_namesz = strlen(name) + 1;
1091 note.n_descsz = data_len;
1092 note.n_type = type;
1093 memcpy(buf, ¬e, sizeof(note));
1094 buf += (sizeof(note) + 3)/4;
1095 memcpy(buf, name, note.n_namesz);
1096 buf += (note.n_namesz + 3)/4;
1097 memcpy(buf, data, note.n_descsz);
1098 buf += (note.n_descsz + 3)/4;
1099
1100 return buf;
1101}
1102
1103static void final_note(u32 *buf)
1104{
1105 struct elf_note note;
1106
1107 note.n_namesz = 0;
1108 note.n_descsz = 0;
1109 note.n_type = 0;
1110 memcpy(buf, ¬e, sizeof(note));
1111}
1112
1113void crash_save_cpu(struct pt_regs *regs, int cpu)
1114{
1115 struct elf_prstatus prstatus;
1116 u32 *buf;
1117
1118 if ((cpu < 0) || (cpu >= nr_cpu_ids))
1119 return;
1120
1121
1122
1123
1124
1125
1126
1127
1128 buf = (u32*)per_cpu_ptr(crash_notes, cpu);
1129 if (!buf)
1130 return;
1131 memset(&prstatus, 0, sizeof(prstatus));
1132 prstatus.pr_pid = current->pid;
1133 elf_core_copy_kernel_regs(&prstatus.pr_reg, regs);
1134 buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
1135 &prstatus, sizeof(prstatus));
1136 final_note(buf);
1137}
1138
1139static int __init crash_notes_memory_init(void)
1140{
1141
1142 crash_notes = alloc_percpu(note_buf_t);
1143 if (!crash_notes) {
1144 printk("Kexec: Memory allocation for saving cpu register"
1145 " states failed\n");
1146 return -ENOMEM;
1147 }
1148 return 0;
1149}
1150module_init(crash_notes_memory_init)
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167static int __init parse_crashkernel_mem(char *cmdline,
1168 unsigned long long system_ram,
1169 unsigned long long *crash_size,
1170 unsigned long long *crash_base)
1171{
1172 char *cur = cmdline, *tmp;
1173
1174
1175 do {
1176 unsigned long long start, end = ULLONG_MAX, size;
1177
1178
1179 start = memparse(cur, &tmp);
1180 if (cur == tmp) {
1181 pr_warning("crashkernel: Memory value expected\n");
1182 return -EINVAL;
1183 }
1184 cur = tmp;
1185 if (*cur != '-') {
1186 pr_warning("crashkernel: '-' expected\n");
1187 return -EINVAL;
1188 }
1189 cur++;
1190
1191
1192 if (*cur != ':') {
1193 end = memparse(cur, &tmp);
1194 if (cur == tmp) {
1195 pr_warning("crashkernel: Memory "
1196 "value expected\n");
1197 return -EINVAL;
1198 }
1199 cur = tmp;
1200 if (end <= start) {
1201 pr_warning("crashkernel: end <= start\n");
1202 return -EINVAL;
1203 }
1204 }
1205
1206 if (*cur != ':') {
1207 pr_warning("crashkernel: ':' expected\n");
1208 return -EINVAL;
1209 }
1210 cur++;
1211
1212 size = memparse(cur, &tmp);
1213 if (cur == tmp) {
1214 pr_warning("Memory value expected\n");
1215 return -EINVAL;
1216 }
1217 cur = tmp;
1218 if (size >= system_ram) {
1219 pr_warning("crashkernel: invalid size\n");
1220 return -EINVAL;
1221 }
1222
1223
1224 if (system_ram >= start && system_ram < end) {
1225 *crash_size = size;
1226 break;
1227 }
1228 } while (*cur++ == ',');
1229
1230 if (*crash_size > 0) {
1231 while (*cur && *cur != ' ' && *cur != '@')
1232 cur++;
1233 if (*cur == '@') {
1234 cur++;
1235 *crash_base = memparse(cur, &tmp);
1236 if (cur == tmp) {
1237 pr_warning("Memory value expected "
1238 "after '@'\n");
1239 return -EINVAL;
1240 }
1241 }
1242 }
1243
1244 return 0;
1245}
1246
1247
1248
1249
1250
1251
1252
1253
1254static int __init parse_crashkernel_simple(char *cmdline,
1255 unsigned long long *crash_size,
1256 unsigned long long *crash_base)
1257{
1258 char *cur = cmdline;
1259
1260 *crash_size = memparse(cmdline, &cur);
1261 if (cmdline == cur) {
1262 pr_warning("crashkernel: memory value expected\n");
1263 return -EINVAL;
1264 }
1265
1266 if (*cur == '@')
1267 *crash_base = memparse(cur+1, &cur);
1268
1269 return 0;
1270}
1271
1272
1273
1274
1275
1276int __init parse_crashkernel(char *cmdline,
1277 unsigned long long system_ram,
1278 unsigned long long *crash_size,
1279 unsigned long long *crash_base)
1280{
1281 char *p = cmdline, *ck_cmdline = NULL;
1282 char *first_colon, *first_space;
1283
1284 BUG_ON(!crash_size || !crash_base);
1285 *crash_size = 0;
1286 *crash_base = 0;
1287
1288
1289 p = strstr(p, "crashkernel=");
1290 while (p) {
1291 ck_cmdline = p;
1292 p = strstr(p+1, "crashkernel=");
1293 }
1294
1295 if (!ck_cmdline)
1296 return -EINVAL;
1297
1298 ck_cmdline += 12;
1299
1300
1301
1302
1303
1304 first_colon = strchr(ck_cmdline, ':');
1305 first_space = strchr(ck_cmdline, ' ');
1306 if (first_colon && (!first_space || first_colon < first_space))
1307 return parse_crashkernel_mem(ck_cmdline, system_ram,
1308 crash_size, crash_base);
1309 else
1310 return parse_crashkernel_simple(ck_cmdline, crash_size,
1311 crash_base);
1312
1313 return 0;
1314}
1315
1316
1317
1318void crash_save_vmcoreinfo(void)
1319{
1320 u32 *buf;
1321
1322 if (!vmcoreinfo_size)
1323 return;
1324
1325 vmcoreinfo_append_str("CRASHTIME=%ld", get_seconds());
1326
1327 buf = (u32 *)vmcoreinfo_note;
1328
1329 buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
1330 vmcoreinfo_size);
1331
1332 final_note(buf);
1333}
1334
1335void vmcoreinfo_append_str(const char *fmt, ...)
1336{
1337 va_list args;
1338 char buf[0x50];
1339 int r;
1340
1341 va_start(args, fmt);
1342 r = vsnprintf(buf, sizeof(buf), fmt, args);
1343 va_end(args);
1344
1345 if (r + vmcoreinfo_size > vmcoreinfo_max_size)
1346 r = vmcoreinfo_max_size - vmcoreinfo_size;
1347
1348 memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
1349
1350 vmcoreinfo_size += r;
1351}
1352
1353
1354
1355
1356
1357void __attribute__ ((weak)) arch_crash_save_vmcoreinfo(void)
1358{}
1359
1360unsigned long __attribute__ ((weak)) paddr_vmcoreinfo_note(void)
1361{
1362 return __pa((unsigned long)(char *)&vmcoreinfo_note);
1363}
1364
1365static int __init crash_save_vmcoreinfo_init(void)
1366{
1367 VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
1368 VMCOREINFO_PAGESIZE(PAGE_SIZE);
1369
1370 VMCOREINFO_SYMBOL(init_uts_ns);
1371 VMCOREINFO_SYMBOL(node_online_map);
1372 VMCOREINFO_SYMBOL(swapper_pg_dir);
1373 VMCOREINFO_SYMBOL(_stext);
1374 VMCOREINFO_SYMBOL(vmlist);
1375
1376#ifndef CONFIG_NEED_MULTIPLE_NODES
1377 VMCOREINFO_SYMBOL(mem_map);
1378 VMCOREINFO_SYMBOL(contig_page_data);
1379#endif
1380#ifdef CONFIG_SPARSEMEM
1381 VMCOREINFO_SYMBOL(mem_section);
1382 VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
1383 VMCOREINFO_STRUCT_SIZE(mem_section);
1384 VMCOREINFO_OFFSET(mem_section, section_mem_map);
1385#endif
1386 VMCOREINFO_STRUCT_SIZE(page);
1387 VMCOREINFO_STRUCT_SIZE(pglist_data);
1388 VMCOREINFO_STRUCT_SIZE(zone);
1389 VMCOREINFO_STRUCT_SIZE(free_area);
1390 VMCOREINFO_STRUCT_SIZE(list_head);
1391 VMCOREINFO_SIZE(nodemask_t);
1392 VMCOREINFO_OFFSET(page, flags);
1393 VMCOREINFO_OFFSET(page, _count);
1394 VMCOREINFO_OFFSET(page, mapping);
1395 VMCOREINFO_OFFSET(page, lru);
1396 VMCOREINFO_OFFSET(pglist_data, node_zones);
1397 VMCOREINFO_OFFSET(pglist_data, nr_zones);
1398#ifdef CONFIG_FLAT_NODE_MEM_MAP
1399 VMCOREINFO_OFFSET(pglist_data, node_mem_map);
1400#endif
1401 VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
1402 VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
1403 VMCOREINFO_OFFSET(pglist_data, node_id);
1404 VMCOREINFO_OFFSET(zone, free_area);
1405 VMCOREINFO_OFFSET(zone, vm_stat);
1406 VMCOREINFO_OFFSET(zone, spanned_pages);
1407 VMCOREINFO_OFFSET(free_area, free_list);
1408 VMCOREINFO_OFFSET(list_head, next);
1409 VMCOREINFO_OFFSET(list_head, prev);
1410 VMCOREINFO_OFFSET(vm_struct, addr);
1411 VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);
1412 log_buf_kexec_setup();
1413 VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
1414 VMCOREINFO_NUMBER(NR_FREE_PAGES);
1415 VMCOREINFO_NUMBER(PG_lru);
1416 VMCOREINFO_NUMBER(PG_private);
1417 VMCOREINFO_NUMBER(PG_swapcache);
1418
1419 arch_crash_save_vmcoreinfo();
1420
1421 return 0;
1422}
1423
1424module_init(crash_save_vmcoreinfo_init)
1425
1426
1427
1428
1429
1430int kernel_kexec(void)
1431{
1432 int error = 0;
1433
1434 if (!mutex_trylock(&kexec_mutex))
1435 return -EBUSY;
1436 if (!kexec_image) {
1437 error = -EINVAL;
1438 goto Unlock;
1439 }
1440
1441#ifdef CONFIG_KEXEC_JUMP
1442 if (kexec_image->preserve_context) {
1443 mutex_lock(&pm_mutex);
1444 pm_prepare_console();
1445 error = freeze_processes();
1446 if (error) {
1447 error = -EBUSY;
1448 goto Restore_console;
1449 }
1450 suspend_console();
1451 error = dpm_suspend_start(PMSG_FREEZE);
1452 if (error)
1453 goto Resume_console;
1454
1455
1456
1457
1458
1459
1460
1461 error = dpm_suspend_noirq(PMSG_FREEZE);
1462 if (error)
1463 goto Resume_devices;
1464 error = disable_nonboot_cpus();
1465 if (error)
1466 goto Enable_cpus;
1467 local_irq_disable();
1468
1469 error = sysdev_suspend(PMSG_FREEZE);
1470 if (error)
1471 goto Enable_irqs;
1472 } else
1473#endif
1474 {
1475 kernel_restart_prepare(NULL);
1476 printk(KERN_EMERG "Starting new kernel\n");
1477 machine_shutdown();
1478 }
1479
1480 machine_kexec(kexec_image);
1481
1482#ifdef CONFIG_KEXEC_JUMP
1483 if (kexec_image->preserve_context) {
1484 sysdev_resume();
1485 Enable_irqs:
1486 local_irq_enable();
1487 Enable_cpus:
1488 enable_nonboot_cpus();
1489 dpm_resume_noirq(PMSG_RESTORE);
1490 Resume_devices:
1491 dpm_resume_end(PMSG_RESTORE);
1492 Resume_console:
1493 resume_console();
1494 thaw_processes();
1495 Restore_console:
1496 pm_restore_console();
1497 mutex_unlock(&pm_mutex);
1498 }
1499#endif
1500
1501 Unlock:
1502 mutex_unlock(&kexec_mutex);
1503 return error;
1504}
1505