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31
32#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
33
34#include <linux/kernel.h>
35#include <linux/init.h>
36#include <linux/efi.h>
37#include <linux/efi-bgrt.h>
38#include <linux/export.h>
39#include <linux/memblock.h>
40#include <linux/slab.h>
41#include <linux/spinlock.h>
42#include <linux/uaccess.h>
43#include <linux/time.h>
44#include <linux/io.h>
45#include <linux/reboot.h>
46#include <linux/bcd.h>
47
48#include <asm/setup.h>
49#include <asm/efi.h>
50#include <asm/e820/api.h>
51#include <asm/time.h>
52#include <asm/tlbflush.h>
53#include <asm/x86_init.h>
54#include <asm/uv/uv.h>
55
56static unsigned long efi_systab_phys __initdata;
57static unsigned long prop_phys = EFI_INVALID_TABLE_ADDR;
58static unsigned long uga_phys = EFI_INVALID_TABLE_ADDR;
59static unsigned long efi_runtime, efi_nr_tables;
60
61unsigned long efi_fw_vendor, efi_config_table;
62
63static const efi_config_table_type_t arch_tables[] __initconst = {
64 {EFI_PROPERTIES_TABLE_GUID, &prop_phys, "PROP" },
65 {UGA_IO_PROTOCOL_GUID, &uga_phys, "UGA" },
66#ifdef CONFIG_X86_UV
67 {UV_SYSTEM_TABLE_GUID, &uv_systab_phys, "UVsystab" },
68#endif
69 {},
70};
71
72static const unsigned long * const efi_tables[] = {
73 &efi.acpi,
74 &efi.acpi20,
75 &efi.smbios,
76 &efi.smbios3,
77 &uga_phys,
78#ifdef CONFIG_X86_UV
79 &uv_systab_phys,
80#endif
81 &efi_fw_vendor,
82 &efi_runtime,
83 &efi_config_table,
84 &efi.esrt,
85 &prop_phys,
86 &efi_mem_attr_table,
87#ifdef CONFIG_EFI_RCI2_TABLE
88 &rci2_table_phys,
89#endif
90 &efi.tpm_log,
91 &efi.tpm_final_log,
92 &efi_rng_seed,
93#ifdef CONFIG_LOAD_UEFI_KEYS
94 &efi.mokvar_table,
95#endif
96};
97
98u64 efi_setup;
99
100static int add_efi_memmap __initdata;
101static int __init setup_add_efi_memmap(char *arg)
102{
103 add_efi_memmap = 1;
104 return 0;
105}
106early_param("add_efi_memmap", setup_add_efi_memmap);
107
108void __init efi_find_mirror(void)
109{
110 efi_memory_desc_t *md;
111 u64 mirror_size = 0, total_size = 0;
112
113 if (!efi_enabled(EFI_MEMMAP))
114 return;
115
116 for_each_efi_memory_desc(md) {
117 unsigned long long start = md->phys_addr;
118 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
119
120 total_size += size;
121 if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
122 memblock_mark_mirror(start, size);
123 mirror_size += size;
124 }
125 }
126 if (mirror_size)
127 pr_info("Memory: %lldM/%lldM mirrored memory\n",
128 mirror_size>>20, total_size>>20);
129}
130
131
132
133
134
135
136
137
138static void __init do_add_efi_memmap(void)
139{
140 efi_memory_desc_t *md;
141
142 if (!efi_enabled(EFI_MEMMAP))
143 return;
144
145 for_each_efi_memory_desc(md) {
146 unsigned long long start = md->phys_addr;
147 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
148 int e820_type;
149
150 switch (md->type) {
151 case EFI_LOADER_CODE:
152 case EFI_LOADER_DATA:
153 case EFI_BOOT_SERVICES_CODE:
154 case EFI_BOOT_SERVICES_DATA:
155 case EFI_CONVENTIONAL_MEMORY:
156 if (efi_soft_reserve_enabled()
157 && (md->attribute & EFI_MEMORY_SP))
158 e820_type = E820_TYPE_SOFT_RESERVED;
159 else if (md->attribute & EFI_MEMORY_WB)
160 e820_type = E820_TYPE_RAM;
161 else
162 e820_type = E820_TYPE_RESERVED;
163 break;
164 case EFI_ACPI_RECLAIM_MEMORY:
165 e820_type = E820_TYPE_ACPI;
166 break;
167 case EFI_ACPI_MEMORY_NVS:
168 e820_type = E820_TYPE_NVS;
169 break;
170 case EFI_UNUSABLE_MEMORY:
171 e820_type = E820_TYPE_UNUSABLE;
172 break;
173 case EFI_PERSISTENT_MEMORY:
174 e820_type = E820_TYPE_PMEM;
175 break;
176 default:
177
178
179
180
181
182 e820_type = E820_TYPE_RESERVED;
183 break;
184 }
185
186 e820__range_add(start, size, e820_type);
187 }
188 e820__update_table(e820_table);
189}
190
191
192
193
194
195
196
197
198static bool do_efi_soft_reserve(void)
199{
200 efi_memory_desc_t *md;
201
202 if (!efi_enabled(EFI_MEMMAP))
203 return false;
204
205 if (!efi_soft_reserve_enabled())
206 return false;
207
208 for_each_efi_memory_desc(md)
209 if (md->type == EFI_CONVENTIONAL_MEMORY &&
210 (md->attribute & EFI_MEMORY_SP))
211 return true;
212 return false;
213}
214
215int __init efi_memblock_x86_reserve_range(void)
216{
217 struct efi_info *e = &boot_params.efi_info;
218 struct efi_memory_map_data data;
219 phys_addr_t pmap;
220 int rv;
221
222 if (efi_enabled(EFI_PARAVIRT))
223 return 0;
224
225
226 if (IS_ENABLED(CONFIG_X86_32) && e->efi_memmap_hi > 0) {
227 pr_err("Memory map is above 4GB, disabling EFI.\n");
228 return -EINVAL;
229 }
230 pmap = (phys_addr_t)(e->efi_memmap | ((u64)e->efi_memmap_hi << 32));
231
232 data.phys_map = pmap;
233 data.size = e->efi_memmap_size;
234 data.desc_size = e->efi_memdesc_size;
235 data.desc_version = e->efi_memdesc_version;
236
237 rv = efi_memmap_init_early(&data);
238 if (rv)
239 return rv;
240
241 if (add_efi_memmap || do_efi_soft_reserve())
242 do_add_efi_memmap();
243
244 efi_fake_memmap_early();
245
246 WARN(efi.memmap.desc_version != 1,
247 "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
248 efi.memmap.desc_version);
249
250 memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
251 set_bit(EFI_PRESERVE_BS_REGIONS, &efi.flags);
252
253 return 0;
254}
255
256#define OVERFLOW_ADDR_SHIFT (64 - EFI_PAGE_SHIFT)
257#define OVERFLOW_ADDR_MASK (U64_MAX << OVERFLOW_ADDR_SHIFT)
258#define U64_HIGH_BIT (~(U64_MAX >> 1))
259
260static bool __init efi_memmap_entry_valid(const efi_memory_desc_t *md, int i)
261{
262 u64 end = (md->num_pages << EFI_PAGE_SHIFT) + md->phys_addr - 1;
263 u64 end_hi = 0;
264 char buf[64];
265
266 if (md->num_pages == 0) {
267 end = 0;
268 } else if (md->num_pages > EFI_PAGES_MAX ||
269 EFI_PAGES_MAX - md->num_pages <
270 (md->phys_addr >> EFI_PAGE_SHIFT)) {
271 end_hi = (md->num_pages & OVERFLOW_ADDR_MASK)
272 >> OVERFLOW_ADDR_SHIFT;
273
274 if ((md->phys_addr & U64_HIGH_BIT) && !(end & U64_HIGH_BIT))
275 end_hi += 1;
276 } else {
277 return true;
278 }
279
280 pr_warn_once(FW_BUG "Invalid EFI memory map entries:\n");
281
282 if (end_hi) {
283 pr_warn("mem%02u: %s range=[0x%016llx-0x%llx%016llx] (invalid)\n",
284 i, efi_md_typeattr_format(buf, sizeof(buf), md),
285 md->phys_addr, end_hi, end);
286 } else {
287 pr_warn("mem%02u: %s range=[0x%016llx-0x%016llx] (invalid)\n",
288 i, efi_md_typeattr_format(buf, sizeof(buf), md),
289 md->phys_addr, end);
290 }
291 return false;
292}
293
294static void __init efi_clean_memmap(void)
295{
296 efi_memory_desc_t *out = efi.memmap.map;
297 const efi_memory_desc_t *in = out;
298 const efi_memory_desc_t *end = efi.memmap.map_end;
299 int i, n_removal;
300
301 for (i = n_removal = 0; in < end; i++) {
302 if (efi_memmap_entry_valid(in, i)) {
303 if (out != in)
304 memcpy(out, in, efi.memmap.desc_size);
305 out = (void *)out + efi.memmap.desc_size;
306 } else {
307 n_removal++;
308 }
309 in = (void *)in + efi.memmap.desc_size;
310 }
311
312 if (n_removal > 0) {
313 struct efi_memory_map_data data = {
314 .phys_map = efi.memmap.phys_map,
315 .desc_version = efi.memmap.desc_version,
316 .desc_size = efi.memmap.desc_size,
317 .size = efi.memmap.desc_size * (efi.memmap.nr_map - n_removal),
318 .flags = 0,
319 };
320
321 pr_warn("Removing %d invalid memory map entries.\n", n_removal);
322 efi_memmap_install(&data);
323 }
324}
325
326void __init efi_print_memmap(void)
327{
328 efi_memory_desc_t *md;
329 int i = 0;
330
331 for_each_efi_memory_desc(md) {
332 char buf[64];
333
334 pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
335 i++, efi_md_typeattr_format(buf, sizeof(buf), md),
336 md->phys_addr,
337 md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1,
338 (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
339 }
340}
341
342static int __init efi_systab_init(unsigned long phys)
343{
344 int size = efi_enabled(EFI_64BIT) ? sizeof(efi_system_table_64_t)
345 : sizeof(efi_system_table_32_t);
346 const efi_table_hdr_t *hdr;
347 bool over4g = false;
348 void *p;
349 int ret;
350
351 hdr = p = early_memremap_ro(phys, size);
352 if (p == NULL) {
353 pr_err("Couldn't map the system table!\n");
354 return -ENOMEM;
355 }
356
357 ret = efi_systab_check_header(hdr, 1);
358 if (ret) {
359 early_memunmap(p, size);
360 return ret;
361 }
362
363 if (efi_enabled(EFI_64BIT)) {
364 const efi_system_table_64_t *systab64 = p;
365
366 efi_runtime = systab64->runtime;
367 over4g = systab64->runtime > U32_MAX;
368
369 if (efi_setup) {
370 struct efi_setup_data *data;
371
372 data = early_memremap_ro(efi_setup, sizeof(*data));
373 if (!data) {
374 early_memunmap(p, size);
375 return -ENOMEM;
376 }
377
378 efi_fw_vendor = (unsigned long)data->fw_vendor;
379 efi_config_table = (unsigned long)data->tables;
380
381 over4g |= data->fw_vendor > U32_MAX ||
382 data->tables > U32_MAX;
383
384 early_memunmap(data, sizeof(*data));
385 } else {
386 efi_fw_vendor = systab64->fw_vendor;
387 efi_config_table = systab64->tables;
388
389 over4g |= systab64->fw_vendor > U32_MAX ||
390 systab64->tables > U32_MAX;
391 }
392 efi_nr_tables = systab64->nr_tables;
393 } else {
394 const efi_system_table_32_t *systab32 = p;
395
396 efi_fw_vendor = systab32->fw_vendor;
397 efi_runtime = systab32->runtime;
398 efi_config_table = systab32->tables;
399 efi_nr_tables = systab32->nr_tables;
400 }
401
402 efi.runtime_version = hdr->revision;
403
404 efi_systab_report_header(hdr, efi_fw_vendor);
405 early_memunmap(p, size);
406
407 if (IS_ENABLED(CONFIG_X86_32) && over4g) {
408 pr_err("EFI data located above 4GB, disabling EFI.\n");
409 return -EINVAL;
410 }
411
412 return 0;
413}
414
415static int __init efi_config_init(const efi_config_table_type_t *arch_tables)
416{
417 void *config_tables;
418 int sz, ret;
419
420 if (efi_nr_tables == 0)
421 return 0;
422
423 if (efi_enabled(EFI_64BIT))
424 sz = sizeof(efi_config_table_64_t);
425 else
426 sz = sizeof(efi_config_table_32_t);
427
428
429
430
431 config_tables = early_memremap(efi_config_table, efi_nr_tables * sz);
432 if (config_tables == NULL) {
433 pr_err("Could not map Configuration table!\n");
434 return -ENOMEM;
435 }
436
437 ret = efi_config_parse_tables(config_tables, efi_nr_tables,
438 arch_tables);
439
440 early_memunmap(config_tables, efi_nr_tables * sz);
441 return ret;
442}
443
444void __init efi_init(void)
445{
446 if (IS_ENABLED(CONFIG_X86_32) &&
447 (boot_params.efi_info.efi_systab_hi ||
448 boot_params.efi_info.efi_memmap_hi)) {
449 pr_info("Table located above 4GB, disabling EFI.\n");
450 return;
451 }
452
453 efi_systab_phys = boot_params.efi_info.efi_systab |
454 ((__u64)boot_params.efi_info.efi_systab_hi << 32);
455
456 if (efi_systab_init(efi_systab_phys))
457 return;
458
459 if (efi_reuse_config(efi_config_table, efi_nr_tables))
460 return;
461
462 if (efi_config_init(arch_tables))
463 return;
464
465
466
467
468
469
470 if (!efi_runtime_supported())
471 pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
472
473 if (!efi_runtime_supported() || efi_runtime_disabled()) {
474 efi_memmap_unmap();
475 return;
476 }
477
478
479 if (prop_phys != EFI_INVALID_TABLE_ADDR) {
480 efi_properties_table_t *tbl;
481
482 tbl = early_memremap_ro(prop_phys, sizeof(*tbl));
483 if (tbl == NULL) {
484 pr_err("Could not map Properties table!\n");
485 } else {
486 if (tbl->memory_protection_attribute &
487 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
488 set_bit(EFI_NX_PE_DATA, &efi.flags);
489
490 early_memunmap(tbl, sizeof(*tbl));
491 }
492 }
493
494 set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
495 efi_clean_memmap();
496
497 if (efi_enabled(EFI_DBG))
498 efi_print_memmap();
499}
500
501
502static void __init efi_merge_regions(void)
503{
504 efi_memory_desc_t *md, *prev_md = NULL;
505
506 for_each_efi_memory_desc(md) {
507 u64 prev_size;
508
509 if (!prev_md) {
510 prev_md = md;
511 continue;
512 }
513
514 if (prev_md->type != md->type ||
515 prev_md->attribute != md->attribute) {
516 prev_md = md;
517 continue;
518 }
519
520 prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
521
522 if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
523 prev_md->num_pages += md->num_pages;
524 md->type = EFI_RESERVED_TYPE;
525 md->attribute = 0;
526 continue;
527 }
528 prev_md = md;
529 }
530}
531
532static void *realloc_pages(void *old_memmap, int old_shift)
533{
534 void *ret;
535
536 ret = (void *)__get_free_pages(GFP_KERNEL, old_shift + 1);
537 if (!ret)
538 goto out;
539
540
541
542
543 if (!old_memmap)
544 return ret;
545
546 memcpy(ret, old_memmap, PAGE_SIZE << old_shift);
547
548out:
549 free_pages((unsigned long)old_memmap, old_shift);
550 return ret;
551}
552
553
554
555
556
557
558
559static inline void *efi_map_next_entry_reverse(void *entry)
560{
561
562 if (!entry)
563 return efi.memmap.map_end - efi.memmap.desc_size;
564
565 entry -= efi.memmap.desc_size;
566 if (entry < efi.memmap.map)
567 return NULL;
568
569 return entry;
570}
571
572
573
574
575
576
577
578
579
580
581
582
583static void *efi_map_next_entry(void *entry)
584{
585 if (efi_enabled(EFI_64BIT)) {
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603 return efi_map_next_entry_reverse(entry);
604 }
605
606
607 if (!entry)
608 return efi.memmap.map;
609
610 entry += efi.memmap.desc_size;
611 if (entry >= efi.memmap.map_end)
612 return NULL;
613
614 return entry;
615}
616
617static bool should_map_region(efi_memory_desc_t *md)
618{
619
620
621
622 if (md->attribute & EFI_MEMORY_RUNTIME)
623 return true;
624
625
626
627
628
629
630 if (IS_ENABLED(CONFIG_X86_32))
631 return false;
632
633
634
635
636
637 if (md->type == EFI_CONVENTIONAL_MEMORY &&
638 efi_soft_reserve_enabled() &&
639 (md->attribute & EFI_MEMORY_SP))
640 return false;
641
642
643
644
645
646 if (efi_is_mixed()) {
647 if (md->type == EFI_CONVENTIONAL_MEMORY ||
648 md->type == EFI_LOADER_DATA ||
649 md->type == EFI_LOADER_CODE)
650 return true;
651 }
652
653
654
655
656
657
658
659 if (md->type == EFI_BOOT_SERVICES_CODE ||
660 md->type == EFI_BOOT_SERVICES_DATA)
661 return true;
662
663 return false;
664}
665
666
667
668
669
670static void * __init efi_map_regions(int *count, int *pg_shift)
671{
672 void *p, *new_memmap = NULL;
673 unsigned long left = 0;
674 unsigned long desc_size;
675 efi_memory_desc_t *md;
676
677 desc_size = efi.memmap.desc_size;
678
679 p = NULL;
680 while ((p = efi_map_next_entry(p))) {
681 md = p;
682
683 if (!should_map_region(md))
684 continue;
685
686 efi_map_region(md);
687
688 if (left < desc_size) {
689 new_memmap = realloc_pages(new_memmap, *pg_shift);
690 if (!new_memmap)
691 return NULL;
692
693 left += PAGE_SIZE << *pg_shift;
694 (*pg_shift)++;
695 }
696
697 memcpy(new_memmap + (*count * desc_size), md, desc_size);
698
699 left -= desc_size;
700 (*count)++;
701 }
702
703 return new_memmap;
704}
705
706static void __init kexec_enter_virtual_mode(void)
707{
708#ifdef CONFIG_KEXEC_CORE
709 efi_memory_desc_t *md;
710 unsigned int num_pages;
711
712
713
714
715
716 if (efi_is_mixed()) {
717 efi_memmap_unmap();
718 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
719 return;
720 }
721
722 if (efi_alloc_page_tables()) {
723 pr_err("Failed to allocate EFI page tables\n");
724 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
725 return;
726 }
727
728
729
730
731
732 for_each_efi_memory_desc(md)
733 efi_map_region_fixed(md);
734
735
736
737
738
739 efi_memmap_unmap();
740
741 if (efi_memmap_init_late(efi.memmap.phys_map,
742 efi.memmap.desc_size * efi.memmap.nr_map)) {
743 pr_err("Failed to remap late EFI memory map\n");
744 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
745 return;
746 }
747
748 num_pages = ALIGN(efi.memmap.nr_map * efi.memmap.desc_size, PAGE_SIZE);
749 num_pages >>= PAGE_SHIFT;
750
751 if (efi_setup_page_tables(efi.memmap.phys_map, num_pages)) {
752 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
753 return;
754 }
755
756 efi_sync_low_kernel_mappings();
757 efi_native_runtime_setup();
758#endif
759}
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777static void __init __efi_enter_virtual_mode(void)
778{
779 int count = 0, pg_shift = 0;
780 void *new_memmap = NULL;
781 efi_status_t status;
782 unsigned long pa;
783
784 if (efi_alloc_page_tables()) {
785 pr_err("Failed to allocate EFI page tables\n");
786 goto err;
787 }
788
789 efi_merge_regions();
790 new_memmap = efi_map_regions(&count, &pg_shift);
791 if (!new_memmap) {
792 pr_err("Error reallocating memory, EFI runtime non-functional!\n");
793 goto err;
794 }
795
796 pa = __pa(new_memmap);
797
798
799
800
801
802
803 efi_memmap_unmap();
804
805 if (efi_memmap_init_late(pa, efi.memmap.desc_size * count)) {
806 pr_err("Failed to remap late EFI memory map\n");
807 goto err;
808 }
809
810 if (efi_enabled(EFI_DBG)) {
811 pr_info("EFI runtime memory map:\n");
812 efi_print_memmap();
813 }
814
815 if (efi_setup_page_tables(pa, 1 << pg_shift))
816 goto err;
817
818 efi_sync_low_kernel_mappings();
819
820 status = efi_set_virtual_address_map(efi.memmap.desc_size * count,
821 efi.memmap.desc_size,
822 efi.memmap.desc_version,
823 (efi_memory_desc_t *)pa,
824 efi_systab_phys);
825 if (status != EFI_SUCCESS) {
826 pr_err("Unable to switch EFI into virtual mode (status=%lx)!\n",
827 status);
828 goto err;
829 }
830
831 efi_check_for_embedded_firmwares();
832 efi_free_boot_services();
833
834 if (!efi_is_mixed())
835 efi_native_runtime_setup();
836 else
837 efi_thunk_runtime_setup();
838
839
840
841
842
843
844 efi_runtime_update_mappings();
845
846
847 efi_delete_dummy_variable();
848 return;
849
850err:
851 clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
852}
853
854void __init efi_enter_virtual_mode(void)
855{
856 if (efi_enabled(EFI_PARAVIRT))
857 return;
858
859 efi.runtime = (efi_runtime_services_t *)efi_runtime;
860
861 if (efi_setup)
862 kexec_enter_virtual_mode();
863 else
864 __efi_enter_virtual_mode();
865
866 efi_dump_pagetable();
867}
868
869bool efi_is_table_address(unsigned long phys_addr)
870{
871 unsigned int i;
872
873 if (phys_addr == EFI_INVALID_TABLE_ADDR)
874 return false;
875
876 for (i = 0; i < ARRAY_SIZE(efi_tables); i++)
877 if (*(efi_tables[i]) == phys_addr)
878 return true;
879
880 return false;
881}
882
883char *efi_systab_show_arch(char *str)
884{
885 if (uga_phys != EFI_INVALID_TABLE_ADDR)
886 str += sprintf(str, "UGA=0x%lx\n", uga_phys);
887 return str;
888}
889
890#define EFI_FIELD(var) efi_ ## var
891
892#define EFI_ATTR_SHOW(name) \
893static ssize_t name##_show(struct kobject *kobj, \
894 struct kobj_attribute *attr, char *buf) \
895{ \
896 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
897}
898
899EFI_ATTR_SHOW(fw_vendor);
900EFI_ATTR_SHOW(runtime);
901EFI_ATTR_SHOW(config_table);
902
903struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
904struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
905struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
906
907umode_t efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n)
908{
909 if (attr == &efi_attr_fw_vendor.attr) {
910 if (efi_enabled(EFI_PARAVIRT) ||
911 efi_fw_vendor == EFI_INVALID_TABLE_ADDR)
912 return 0;
913 } else if (attr == &efi_attr_runtime.attr) {
914 if (efi_runtime == EFI_INVALID_TABLE_ADDR)
915 return 0;
916 } else if (attr == &efi_attr_config_table.attr) {
917 if (efi_config_table == EFI_INVALID_TABLE_ADDR)
918 return 0;
919 }
920 return attr->mode;
921}
922