1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 1995 Linus Torvalds
5 * This file contains the setup_arch() code, which handles the architecture-dependent
6 * parts of early kernel initialization.
8 #include <linux/acpi.h>
9 #include <linux/console.h>
10 #include <linux/crash_dump.h>
11 #include <linux/dma-map-ops.h>
12 #include <linux/dmi.h>
13 #include <linux/efi.h>
14 #include <linux/init_ohci1394_dma.h>
15 #include <linux/initrd.h>
16 #include <linux/iscsi_ibft.h>
17 #include <linux/memblock.h>
18 #include <linux/panic_notifier.h>
19 #include <linux/pci.h>
20 #include <linux/root_dev.h>
21 #include <linux/hugetlb.h>
22 #include <linux/tboot.h>
23 #include <linux/usb/xhci-dbgp.h>
24 #include <linux/static_call.h>
25 #include <linux/swiotlb.h>
27 #include <uapi/linux/mount.h>
33 #include <asm/bios_ebda.h>
38 #include <asm/hypervisor.h>
39 #include <asm/io_apic.h>
40 #include <asm/kasan.h>
41 #include <asm/kaslr.h>
44 #include <asm/realmode.h>
45 #include <asm/olpc_ofw.h>
46 #include <asm/pci-direct.h>
48 #include <asm/proto.h>
49 #include <asm/thermal.h>
50 #include <asm/unwind.h>
51 #include <asm/vsyscall.h>
52 #include <linux/vmalloc.h>
55 * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
56 * max_pfn_mapped: highest directly mapped pfn > 4 GB
58 * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
59 * represented by pfn_mapped[].
61 unsigned long max_low_pfn_mapped;
62 unsigned long max_pfn_mapped;
65 RESERVE_BRK(dmi_alloc, 65536);
70 * Range of the BSS area. The size of the BSS area is determined
71 * at link time, with RESERVE_BRK() facility reserving additional
74 unsigned long _brk_start = (unsigned long)__brk_base;
75 unsigned long _brk_end = (unsigned long)__brk_base;
77 struct boot_params boot_params;
80 * These are the four main kernel memory regions, we put them into
81 * the resource tree so that kdump tools and other debugging tools
85 static struct resource rodata_resource = {
86 .name = "Kernel rodata",
89 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
92 static struct resource data_resource = {
93 .name = "Kernel data",
96 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
99 static struct resource code_resource = {
100 .name = "Kernel code",
103 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
106 static struct resource bss_resource = {
107 .name = "Kernel bss",
110 .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
115 /* CPU data as detected by the assembly code in head_32.S */
116 struct cpuinfo_x86 new_cpu_data;
118 /* Common CPU data for all CPUs */
119 struct cpuinfo_x86 boot_cpu_data __read_mostly;
120 EXPORT_SYMBOL(boot_cpu_data);
122 unsigned int def_to_bigsmp;
124 struct apm_info apm_info;
125 EXPORT_SYMBOL(apm_info);
127 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
128 defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
129 struct ist_info ist_info;
130 EXPORT_SYMBOL(ist_info);
132 struct ist_info ist_info;
136 struct cpuinfo_x86 boot_cpu_data __read_mostly;
137 EXPORT_SYMBOL(boot_cpu_data);
141 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
142 __visible unsigned long mmu_cr4_features __ro_after_init;
144 __visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE;
147 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
148 int bootloader_type, bootloader_version;
153 struct screen_info screen_info;
154 EXPORT_SYMBOL(screen_info);
155 struct edid_info edid_info;
156 EXPORT_SYMBOL_GPL(edid_info);
158 extern int root_mountflags;
160 unsigned long saved_video_mode;
162 #define RAMDISK_IMAGE_START_MASK 0x07FF
163 #define RAMDISK_PROMPT_FLAG 0x8000
164 #define RAMDISK_LOAD_FLAG 0x4000
166 static char __initdata command_line[COMMAND_LINE_SIZE];
167 #ifdef CONFIG_CMDLINE_BOOL
168 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
171 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
173 #ifdef CONFIG_EDD_MODULE
177 * copy_edd() - Copy the BIOS EDD information
178 * from boot_params into a safe place.
181 static inline void __init copy_edd(void)
183 memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
184 sizeof(edd.mbr_signature));
185 memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
186 edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
187 edd.edd_info_nr = boot_params.eddbuf_entries;
190 static inline void __init copy_edd(void)
195 void * __init extend_brk(size_t size, size_t align)
197 size_t mask = align - 1;
200 BUG_ON(_brk_start == 0);
201 BUG_ON(align & mask);
203 _brk_end = (_brk_end + mask) & ~mask;
204 BUG_ON((char *)(_brk_end + size) > __brk_limit);
206 ret = (void *)_brk_end;
209 memset(ret, 0, size);
215 static void __init cleanup_highmap(void)
220 static void __init reserve_brk(void)
222 if (_brk_end > _brk_start)
223 memblock_reserve(__pa_symbol(_brk_start),
224 _brk_end - _brk_start);
226 /* Mark brk area as locked down and no longer taking any
231 u64 relocated_ramdisk;
233 #ifdef CONFIG_BLK_DEV_INITRD
235 static u64 __init get_ramdisk_image(void)
237 u64 ramdisk_image = boot_params.hdr.ramdisk_image;
239 ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
241 if (ramdisk_image == 0)
242 ramdisk_image = phys_initrd_start;
244 return ramdisk_image;
246 static u64 __init get_ramdisk_size(void)
248 u64 ramdisk_size = boot_params.hdr.ramdisk_size;
250 ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
252 if (ramdisk_size == 0)
253 ramdisk_size = phys_initrd_size;
258 static void __init relocate_initrd(void)
260 /* Assume only end is not page aligned */
261 u64 ramdisk_image = get_ramdisk_image();
262 u64 ramdisk_size = get_ramdisk_size();
263 u64 area_size = PAGE_ALIGN(ramdisk_size);
265 /* We need to move the initrd down into directly mapped mem */
266 relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
267 PFN_PHYS(max_pfn_mapped));
268 if (!relocated_ramdisk)
269 panic("Cannot find place for new RAMDISK of size %lld\n",
272 initrd_start = relocated_ramdisk + PAGE_OFFSET;
273 initrd_end = initrd_start + ramdisk_size;
274 printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
275 relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
277 copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
279 printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
280 " [mem %#010llx-%#010llx]\n",
281 ramdisk_image, ramdisk_image + ramdisk_size - 1,
282 relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
285 static void __init early_reserve_initrd(void)
287 /* Assume only end is not page aligned */
288 u64 ramdisk_image = get_ramdisk_image();
289 u64 ramdisk_size = get_ramdisk_size();
290 u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size);
292 if (!boot_params.hdr.type_of_loader ||
293 !ramdisk_image || !ramdisk_size)
294 return; /* No initrd provided by bootloader */
296 memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
299 static void __init reserve_initrd(void)
301 /* Assume only end is not page aligned */
302 u64 ramdisk_image = get_ramdisk_image();
303 u64 ramdisk_size = get_ramdisk_size();
304 u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size);
306 if (!boot_params.hdr.type_of_loader ||
307 !ramdisk_image || !ramdisk_size)
308 return; /* No initrd provided by bootloader */
312 printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
315 if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
316 PFN_DOWN(ramdisk_end))) {
317 /* All are mapped, easy case */
318 initrd_start = ramdisk_image + PAGE_OFFSET;
319 initrd_end = initrd_start + ramdisk_size;
325 memblock_free(ramdisk_image, ramdisk_end - ramdisk_image);
329 static void __init early_reserve_initrd(void)
332 static void __init reserve_initrd(void)
335 #endif /* CONFIG_BLK_DEV_INITRD */
337 static void __init parse_setup_data(void)
339 struct setup_data *data;
340 u64 pa_data, pa_next;
342 pa_data = boot_params.hdr.setup_data;
344 u32 data_len, data_type;
346 data = early_memremap(pa_data, sizeof(*data));
347 data_len = data->len + sizeof(struct setup_data);
348 data_type = data->type;
349 pa_next = data->next;
350 early_memunmap(data, sizeof(*data));
354 e820__memory_setup_extended(pa_data, data_len);
360 parse_efi_setup(pa_data, data_len);
369 static void __init memblock_x86_reserve_range_setup_data(void)
371 struct setup_data *data;
374 pa_data = boot_params.hdr.setup_data;
376 data = early_memremap(pa_data, sizeof(*data));
377 memblock_reserve(pa_data, sizeof(*data) + data->len);
379 if (data->type == SETUP_INDIRECT &&
380 ((struct setup_indirect *)data->data)->type != SETUP_INDIRECT)
381 memblock_reserve(((struct setup_indirect *)data->data)->addr,
382 ((struct setup_indirect *)data->data)->len);
384 pa_data = data->next;
385 early_memunmap(data, sizeof(*data));
390 * --------- Crashkernel reservation ------------------------------
393 #ifdef CONFIG_KEXEC_CORE
395 /* 16M alignment for crash kernel regions */
396 #define CRASH_ALIGN SZ_16M
399 * Keep the crash kernel below this limit.
401 * Earlier 32-bits kernels would limit the kernel to the low 512 MB range
402 * due to mapping restrictions.
404 * 64-bit kdump kernels need to be restricted to be under 64 TB, which is
405 * the upper limit of system RAM in 4-level paging mode. Since the kdump
406 * jump could be from 5-level paging to 4-level paging, the jump will fail if
407 * the kernel is put above 64 TB, and during the 1st kernel bootup there's
408 * no good way to detect the paging mode of the target kernel which will be
409 * loaded for dumping.
412 # define CRASH_ADDR_LOW_MAX SZ_512M
413 # define CRASH_ADDR_HIGH_MAX SZ_512M
415 # define CRASH_ADDR_LOW_MAX SZ_4G
416 # define CRASH_ADDR_HIGH_MAX SZ_64T
419 static int __init reserve_crashkernel_low(void)
422 unsigned long long base, low_base = 0, low_size = 0;
423 unsigned long low_mem_limit;
426 low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX);
428 /* crashkernel=Y,low */
429 ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base);
432 * two parts from kernel/dma/swiotlb.c:
433 * -swiotlb size: user-specified with swiotlb= or default.
435 * -swiotlb overflow buffer: now hardcoded to 32k. We round it
436 * to 8M for other buffers that may need to stay low too. Also
437 * make sure we allocate enough extra low memory so that we
438 * don't run out of DMA buffers for 32-bit devices.
440 low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20);
442 /* passed with crashkernel=0,low ? */
447 low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
449 pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
450 (unsigned long)(low_size >> 20));
454 pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n",
455 (unsigned long)(low_size >> 20),
456 (unsigned long)(low_base >> 20),
457 (unsigned long)(low_mem_limit >> 20));
459 crashk_low_res.start = low_base;
460 crashk_low_res.end = low_base + low_size - 1;
461 insert_resource(&iomem_resource, &crashk_low_res);
466 static void __init reserve_crashkernel(void)
468 unsigned long long crash_size, crash_base, total_mem;
472 total_mem = memblock_phys_mem_size();
475 ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base);
476 if (ret != 0 || crash_size <= 0) {
477 /* crashkernel=X,high */
478 ret = parse_crashkernel_high(boot_command_line, total_mem,
479 &crash_size, &crash_base);
480 if (ret != 0 || crash_size <= 0)
485 if (xen_pv_domain()) {
486 pr_info("Ignoring crashkernel for a Xen PV domain\n");
490 /* 0 means: find the address automatically */
493 * Set CRASH_ADDR_LOW_MAX upper bound for crash memory,
494 * crashkernel=x,high reserves memory over 4G, also allocates
495 * 256M extra low memory for DMA buffers and swiotlb.
496 * But the extra memory is not required for all machines.
497 * So try low memory first and fall back to high memory
498 * unless "crashkernel=size[KMG],high" is specified.
501 crash_base = memblock_phys_alloc_range(crash_size,
502 CRASH_ALIGN, CRASH_ALIGN,
505 crash_base = memblock_phys_alloc_range(crash_size,
506 CRASH_ALIGN, CRASH_ALIGN,
507 CRASH_ADDR_HIGH_MAX);
509 pr_info("crashkernel reservation failed - No suitable area found.\n");
513 unsigned long long start;
515 start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
516 crash_base + crash_size);
517 if (start != crash_base) {
518 pr_info("crashkernel reservation failed - memory is in use.\n");
523 if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) {
524 memblock_free(crash_base, crash_size);
528 pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
529 (unsigned long)(crash_size >> 20),
530 (unsigned long)(crash_base >> 20),
531 (unsigned long)(total_mem >> 20));
533 crashk_res.start = crash_base;
534 crashk_res.end = crash_base + crash_size - 1;
535 insert_resource(&iomem_resource, &crashk_res);
538 static void __init reserve_crashkernel(void)
543 static struct resource standard_io_resources[] = {
544 { .name = "dma1", .start = 0x00, .end = 0x1f,
545 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
546 { .name = "pic1", .start = 0x20, .end = 0x21,
547 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
548 { .name = "timer0", .start = 0x40, .end = 0x43,
549 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
550 { .name = "timer1", .start = 0x50, .end = 0x53,
551 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
552 { .name = "keyboard", .start = 0x60, .end = 0x60,
553 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
554 { .name = "keyboard", .start = 0x64, .end = 0x64,
555 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
556 { .name = "dma page reg", .start = 0x80, .end = 0x8f,
557 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
558 { .name = "pic2", .start = 0xa0, .end = 0xa1,
559 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
560 { .name = "dma2", .start = 0xc0, .end = 0xdf,
561 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
562 { .name = "fpu", .start = 0xf0, .end = 0xff,
563 .flags = IORESOURCE_BUSY | IORESOURCE_IO }
566 void __init reserve_standard_io_resources(void)
570 /* request I/O space for devices used on all i[345]86 PCs */
571 for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
572 request_resource(&ioport_resource, &standard_io_resources[i]);
576 static bool __init snb_gfx_workaround_needed(void)
581 static const __initconst u16 snb_ids[] = {
591 /* Assume no if something weird is going on with PCI */
592 if (!early_pci_allowed())
595 vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
596 if (vendor != 0x8086)
599 devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
600 for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
601 if (devid == snb_ids[i])
609 * Sandy Bridge graphics has trouble with certain ranges, exclude
610 * them from allocation.
612 static void __init trim_snb_memory(void)
614 static const __initconst unsigned long bad_pages[] = {
623 if (!snb_gfx_workaround_needed())
626 printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
629 * SandyBridge integrated graphics devices have a bug that prevents
630 * them from accessing certain memory ranges, namely anything below
631 * 1M and in the pages listed in bad_pages[] above.
633 * To avoid these pages being ever accessed by SNB gfx devices reserve
634 * bad_pages that have not already been reserved at boot time.
635 * All memory below the 1 MB mark is anyway reserved later during
636 * setup_arch(), so there is no need to reserve it here.
639 for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
640 if (memblock_reserve(bad_pages[i], PAGE_SIZE))
641 printk(KERN_WARNING "failed to reserve 0x%08lx\n",
646 static void __init trim_bios_range(void)
649 * A special case is the first 4Kb of memory;
650 * This is a BIOS owned area, not kernel ram, but generally
651 * not listed as such in the E820 table.
653 * This typically reserves additional memory (64KiB by default)
654 * since some BIOSes are known to corrupt low memory. See the
655 * Kconfig help text for X86_RESERVE_LOW.
657 e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
660 * special case: Some BIOSes report the PC BIOS
661 * area (640Kb -> 1Mb) as RAM even though it is not.
664 e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
666 e820__update_table(e820_table);
669 /* called before trim_bios_range() to spare extra sanitize */
670 static void __init e820_add_kernel_range(void)
672 u64 start = __pa_symbol(_text);
673 u64 size = __pa_symbol(_end) - start;
676 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
677 * attempt to fix it by adding the range. We may have a confused BIOS,
678 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
679 * exclude kernel range. If we really are running on top non-RAM,
680 * we will crash later anyways.
682 if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
685 pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
686 e820__range_remove(start, size, E820_TYPE_RAM, 0);
687 e820__range_add(start, size, E820_TYPE_RAM);
690 static void __init early_reserve_memory(void)
693 * Reserve the memory occupied by the kernel between _text and
694 * __end_of_kernel_reserve symbols. Any kernel sections after the
695 * __end_of_kernel_reserve symbol must be explicitly reserved with a
696 * separate memblock_reserve() or they will be discarded.
698 memblock_reserve(__pa_symbol(_text),
699 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
702 * The first 4Kb of memory is a BIOS owned area, but generally it is
703 * not listed as such in the E820 table.
705 * Reserve the first 64K of memory since some BIOSes are known to
706 * corrupt low memory. After the real mode trampoline is allocated the
707 * rest of the memory below 640k is reserved.
709 * In addition, make sure page 0 is always reserved because on
710 * systems with L1TF its contents can be leaked to user processes.
712 memblock_reserve(0, SZ_64K);
714 early_reserve_initrd();
716 if (efi_enabled(EFI_BOOT))
717 efi_memblock_x86_reserve_range();
719 memblock_x86_reserve_range_setup_data();
721 reserve_ibft_region();
722 reserve_bios_regions();
727 * Dump out kernel offset information on panic.
730 dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
732 if (kaslr_enabled()) {
733 pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
739 pr_emerg("Kernel Offset: disabled\n");
746 * Determine if we were loaded by an EFI loader. If so, then we have also been
747 * passed the efi memmap, systab, etc., so we should use these data structures
748 * for initialization. Note, the efi init code path is determined by the
749 * global efi_enabled. This allows the same kernel image to be used on existing
750 * systems (with a traditional BIOS) as well as on EFI systems.
753 * setup_arch - architecture-specific boot-time initializations
755 * Note: On x86_64, fixmaps are ready for use even before this is called.
758 void __init setup_arch(char **cmdline_p)
761 memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
764 * copy kernel address range established so far and switch
765 * to the proper swapper page table
767 clone_pgd_range(swapper_pg_dir + KERNEL_PGD_BOUNDARY,
768 initial_page_table + KERNEL_PGD_BOUNDARY,
771 load_cr3(swapper_pg_dir);
773 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
774 * a cr3 based tlb flush, so the following __flush_tlb_all()
775 * will not flush anything because the CPU quirk which clears
776 * X86_FEATURE_PGE has not been invoked yet. Though due to the
777 * load_cr3() above the TLB has been flushed already. The
778 * quirk is invoked before subsequent calls to __flush_tlb_all()
779 * so proper operation is guaranteed.
783 printk(KERN_INFO "Command line: %s\n", boot_command_line);
784 boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
788 * If we have OLPC OFW, we might end up relocating the fixmap due to
789 * reserve_top(), so do this before touching the ioremap area.
793 idt_setup_early_traps();
797 early_ioremap_init();
799 setup_olpc_ofw_pgd();
801 ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
802 screen_info = boot_params.screen_info;
803 edid_info = boot_params.edid_info;
805 apm_info.bios = boot_params.apm_bios_info;
806 ist_info = boot_params.ist_info;
808 saved_video_mode = boot_params.hdr.vid_mode;
809 bootloader_type = boot_params.hdr.type_of_loader;
810 if ((bootloader_type >> 4) == 0xe) {
811 bootloader_type &= 0xf;
812 bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
814 bootloader_version = bootloader_type & 0xf;
815 bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
817 #ifdef CONFIG_BLK_DEV_RAM
818 rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
821 if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
822 EFI32_LOADER_SIGNATURE, 4)) {
823 set_bit(EFI_BOOT, &efi.flags);
824 } else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
825 EFI64_LOADER_SIGNATURE, 4)) {
826 set_bit(EFI_BOOT, &efi.flags);
827 set_bit(EFI_64BIT, &efi.flags);
831 x86_init.oem.arch_setup();
833 iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
834 e820__memory_setup();
839 if (!boot_params.hdr.root_flags)
840 root_mountflags &= ~MS_RDONLY;
841 setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
843 code_resource.start = __pa_symbol(_text);
844 code_resource.end = __pa_symbol(_etext)-1;
845 rodata_resource.start = __pa_symbol(__start_rodata);
846 rodata_resource.end = __pa_symbol(__end_rodata)-1;
847 data_resource.start = __pa_symbol(_sdata);
848 data_resource.end = __pa_symbol(_edata)-1;
849 bss_resource.start = __pa_symbol(__bss_start);
850 bss_resource.end = __pa_symbol(__bss_stop)-1;
852 #ifdef CONFIG_CMDLINE_BOOL
853 #ifdef CONFIG_CMDLINE_OVERRIDE
854 strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
856 if (builtin_cmdline[0]) {
857 /* append boot loader cmdline to builtin */
858 strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
859 strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
860 strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
865 strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
866 *cmdline_p = command_line;
869 * x86_configure_nx() is called before parse_early_param() to detect
870 * whether hardware doesn't support NX (so that the early EHCI debug
871 * console setup can safely call set_fixmap()). It may then be called
872 * again from within noexec_setup() during parsing early parameters
873 * to honor the respective command line option.
880 * Do some memory reservations *before* memory is added to
881 * memblock, so memblock allocations won't overwrite it.
882 * Do it after early param, so we could get (unlikely) panic from
885 * After this point everything still needed from the boot loader or
886 * firmware or kernel text should be early reserved or marked not
887 * RAM in e820. All other memory is free game.
889 early_reserve_memory();
891 #ifdef CONFIG_MEMORY_HOTPLUG
893 * Memory used by the kernel cannot be hot-removed because Linux
894 * cannot migrate the kernel pages. When memory hotplug is
895 * enabled, we should prevent memblock from allocating memory
898 * ACPI SRAT records all hotpluggable memory ranges. But before
899 * SRAT is parsed, we don't know about it.
901 * The kernel image is loaded into memory at very early time. We
902 * cannot prevent this anyway. So on NUMA system, we set any
903 * node the kernel resides in as un-hotpluggable.
905 * Since on modern servers, one node could have double-digit
906 * gigabytes memory, we can assume the memory around the kernel
907 * image is also un-hotpluggable. So before SRAT is parsed, just
908 * allocate memory near the kernel image to try the best to keep
909 * the kernel away from hotpluggable memory.
911 if (movable_node_is_enabled())
912 memblock_set_bottom_up(true);
917 if (acpi_mps_check()) {
918 #ifdef CONFIG_X86_LOCAL_APIC
921 setup_clear_cpu_cap(X86_FEATURE_APIC);
924 e820__reserve_setup_data();
925 e820__finish_early_params();
927 if (efi_enabled(EFI_BOOT))
933 * VMware detection requires dmi to be available, so this
934 * needs to be done after dmi_setup(), for the boot CPU.
936 init_hypervisor_platform();
939 x86_init.resources.probe_roms();
941 /* after parse_early_param, so could debug it */
942 insert_resource(&iomem_resource, &code_resource);
943 insert_resource(&iomem_resource, &rodata_resource);
944 insert_resource(&iomem_resource, &data_resource);
945 insert_resource(&iomem_resource, &bss_resource);
947 e820_add_kernel_range();
950 if (ppro_with_ram_bug()) {
951 e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
953 e820__update_table(e820_table);
954 printk(KERN_INFO "fixed physical RAM map:\n");
955 e820__print_table("bad_ppro");
958 early_gart_iommu_check();
962 * partially used pages are not usable - thus
963 * we are rounding upwards:
965 max_pfn = e820__end_of_ram_pfn();
967 /* update e820 for memory not covered by WB MTRRs */
969 if (mtrr_trim_uncached_memory(max_pfn))
970 max_pfn = e820__end_of_ram_pfn();
972 max_possible_pfn = max_pfn;
975 * This call is required when the CPU does not support PAT. If
976 * mtrr_bp_init() invoked it already via pat_init() the call has no
982 * Define random base addresses for memory sections after max_pfn is
983 * defined and before each memory section base is used.
985 kernel_randomize_memory();
988 /* max_low_pfn get updated here */
989 find_low_pfn_range();
993 /* How many end-of-memory variables you have, grandma! */
994 /* need this before calling reserve_initrd */
995 if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
996 max_low_pfn = e820__end_of_low_ram_pfn();
998 max_low_pfn = max_pfn;
1000 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
1004 * Find and reserve possible boot-time SMP configuration:
1008 early_alloc_pgt_buf();
1011 * Need to conclude brk, before e820__memblock_setup()
1012 * it could use memblock_find_in_range, could overlap with
1019 memblock_set_current_limit(ISA_END_ADDRESS);
1020 e820__memblock_setup();
1023 * Needs to run after memblock setup because it needs the physical
1031 efi_mokvar_table_init();
1034 * The EFI specification says that boot service code won't be
1035 * called after ExitBootServices(). This is, in fact, a lie.
1037 efi_reserve_boot_services();
1039 /* preallocate 4k for mptable mpc */
1040 e820__memblock_alloc_reserved_mpc_new();
1042 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1043 setup_bios_corruption_check();
1046 #ifdef CONFIG_X86_32
1047 printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1048 (max_pfn_mapped<<PAGE_SHIFT) - 1);
1052 * Find free memory for the real mode trampoline and place it there. If
1053 * there is not enough free memory under 1M, on EFI-enabled systems
1054 * there will be additional attempt to reclaim the memory for the real
1055 * mode trampoline at efi_free_boot_services().
1057 * Unconditionally reserve the entire first 1M of RAM because BIOSes
1058 * are known to corrupt low memory and several hundred kilobytes are not
1059 * worth complex detection what memory gets clobbered. Windows does the
1060 * same thing for very similar reasons.
1062 * Moreover, on machines with SandyBridge graphics or in setups that use
1063 * crashkernel the entire 1M is reserved anyway.
1065 reserve_real_mode();
1069 idt_setup_early_pf();
1072 * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features)
1073 * with the current CR4 value. This may not be necessary, but
1074 * auditing all the early-boot CR4 manipulation would be needed to
1077 * Mask off features that don't work outside long mode (just
1080 mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE;
1082 memblock_set_current_limit(get_max_mapped());
1085 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1088 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1089 if (init_ohci1394_dma_early)
1090 init_ohci1394_dma_on_all_controllers();
1092 /* Allocate bigger log buffer */
1095 if (efi_enabled(EFI_BOOT)) {
1096 switch (boot_params.secure_boot) {
1097 case efi_secureboot_mode_disabled:
1098 pr_info("Secure boot disabled\n");
1100 case efi_secureboot_mode_enabled:
1101 pr_info("Secure boot enabled\n");
1104 pr_info("Secure boot could not be determined\n");
1111 acpi_table_upgrade();
1112 /* Look for ACPI tables and reserve memory occupied by them. */
1113 acpi_boot_table_init();
1119 early_platform_quirks();
1121 early_acpi_boot_init();
1124 dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1126 if (boot_cpu_has(X86_FEATURE_GBPAGES))
1127 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1130 * Reserve memory for crash kernel after SRAT is parsed so that it
1131 * won't consume hotpluggable memory.
1133 reserve_crashkernel();
1135 memblock_find_dma_reserve();
1137 if (!early_xdbc_setup_hardware())
1138 early_xdbc_register_console();
1140 x86_init.paging.pagetable_init();
1145 * Sync back kernel address range.
1147 * FIXME: Can the later sync in setup_cpu_entry_areas() replace
1150 sync_initial_page_table();
1156 generic_apic_probe();
1161 * Read APIC and some other early information from ACPI tables.
1167 * get boot-time SMP configuration:
1172 * Systems w/o ACPI and mptables might not have it mapped the local
1173 * APIC yet, but prefill_possible_map() might need to access it.
1175 init_apic_mappings();
1177 prefill_possible_map();
1182 io_apic_init_mappings();
1184 x86_init.hyper.guest_late_init();
1186 e820__reserve_resources();
1187 e820__register_nosave_regions(max_pfn);
1189 x86_init.resources.reserve_resources();
1191 e820__setup_pci_gap();
1194 #if defined(CONFIG_VGA_CONSOLE)
1195 if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1196 conswitchp = &vga_con;
1199 x86_init.oem.banner();
1201 x86_init.timers.wallclock_init();
1204 * This needs to run before setup_local_APIC() which soft-disables the
1205 * local APIC temporarily and that masks the thermal LVT interrupt,
1206 * leading to softlockups on machines which have configured SMI
1207 * interrupt delivery.
1213 register_refined_jiffies(CLOCK_TICK_RATE);
1216 if (efi_enabled(EFI_BOOT))
1217 efi_apply_memmap_quirks();
1223 #ifdef CONFIG_X86_32
1225 static struct resource video_ram_resource = {
1226 .name = "Video RAM area",
1229 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
1232 void __init i386_reserve_resources(void)
1234 request_resource(&iomem_resource, &video_ram_resource);
1235 reserve_standard_io_resources();
1238 #endif /* CONFIG_X86_32 */
1240 static struct notifier_block kernel_offset_notifier = {
1241 .notifier_call = dump_kernel_offset
1244 static int __init register_kernel_offset_dumper(void)
1246 atomic_notifier_chain_register(&panic_notifier_list,
1247 &kernel_offset_notifier);
1250 __initcall(register_kernel_offset_dumper);