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/ima.h>
15 #include <linux/init_ohci1394_dma.h>
16 #include <linux/initrd.h>
17 #include <linux/iscsi_ibft.h>
18 #include <linux/memblock.h>
19 #include <linux/panic_notifier.h>
20 #include <linux/pci.h>
21 #include <linux/root_dev.h>
22 #include <linux/hugetlb.h>
23 #include <linux/tboot.h>
24 #include <linux/usb/xhci-dbgp.h>
25 #include <linux/static_call.h>
26 #include <linux/swiotlb.h>
27 #include <linux/random.h>
29 #include <uapi/linux/mount.h>
36 #include <asm/bios_ebda.h>
38 #include <asm/cacheinfo.h>
42 #include <asm/hypervisor.h>
43 #include <asm/io_apic.h>
44 #include <asm/kasan.h>
45 #include <asm/kaslr.h>
47 #include <asm/memtype.h>
49 #include <asm/realmode.h>
50 #include <asm/olpc_ofw.h>
51 #include <asm/pci-direct.h>
53 #include <asm/proto.h>
54 #include <asm/thermal.h>
55 #include <asm/unwind.h>
56 #include <asm/vsyscall.h>
57 #include <linux/vmalloc.h>
60 * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
61 * max_pfn_mapped: highest directly mapped pfn > 4 GB
63 * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
64 * represented by pfn_mapped[].
66 unsigned long max_low_pfn_mapped;
67 unsigned long max_pfn_mapped;
70 RESERVE_BRK(dmi_alloc, 65536);
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;
148 static phys_addr_t ima_kexec_buffer_phys;
149 static size_t ima_kexec_buffer_size;
152 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
153 int bootloader_type, bootloader_version;
158 struct screen_info screen_info;
159 EXPORT_SYMBOL(screen_info);
160 struct edid_info edid_info;
161 EXPORT_SYMBOL_GPL(edid_info);
163 extern int root_mountflags;
165 unsigned long saved_video_mode;
167 #define RAMDISK_IMAGE_START_MASK 0x07FF
168 #define RAMDISK_PROMPT_FLAG 0x8000
169 #define RAMDISK_LOAD_FLAG 0x4000
171 static char __initdata command_line[COMMAND_LINE_SIZE];
172 #ifdef CONFIG_CMDLINE_BOOL
173 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
176 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
178 #ifdef CONFIG_EDD_MODULE
182 * copy_edd() - Copy the BIOS EDD information
183 * from boot_params into a safe place.
186 static inline void __init copy_edd(void)
188 memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
189 sizeof(edd.mbr_signature));
190 memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
191 edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
192 edd.edd_info_nr = boot_params.eddbuf_entries;
195 static inline void __init copy_edd(void)
200 void * __init extend_brk(size_t size, size_t align)
202 size_t mask = align - 1;
205 BUG_ON(_brk_start == 0);
206 BUG_ON(align & mask);
208 _brk_end = (_brk_end + mask) & ~mask;
209 BUG_ON((char *)(_brk_end + size) > __brk_limit);
211 ret = (void *)_brk_end;
214 memset(ret, 0, size);
220 static void __init cleanup_highmap(void)
225 static void __init reserve_brk(void)
227 if (_brk_end > _brk_start)
228 memblock_reserve(__pa_symbol(_brk_start),
229 _brk_end - _brk_start);
231 /* Mark brk area as locked down and no longer taking any
236 u64 relocated_ramdisk;
238 #ifdef CONFIG_BLK_DEV_INITRD
240 static u64 __init get_ramdisk_image(void)
242 u64 ramdisk_image = boot_params.hdr.ramdisk_image;
244 ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
246 if (ramdisk_image == 0)
247 ramdisk_image = phys_initrd_start;
249 return ramdisk_image;
251 static u64 __init get_ramdisk_size(void)
253 u64 ramdisk_size = boot_params.hdr.ramdisk_size;
255 ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
257 if (ramdisk_size == 0)
258 ramdisk_size = phys_initrd_size;
263 static void __init relocate_initrd(void)
265 /* Assume only end is not page aligned */
266 u64 ramdisk_image = get_ramdisk_image();
267 u64 ramdisk_size = get_ramdisk_size();
268 u64 area_size = PAGE_ALIGN(ramdisk_size);
270 /* We need to move the initrd down into directly mapped mem */
271 relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
272 PFN_PHYS(max_pfn_mapped));
273 if (!relocated_ramdisk)
274 panic("Cannot find place for new RAMDISK of size %lld\n",
277 initrd_start = relocated_ramdisk + PAGE_OFFSET;
278 initrd_end = initrd_start + ramdisk_size;
279 printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
280 relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
282 copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
284 printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
285 " [mem %#010llx-%#010llx]\n",
286 ramdisk_image, ramdisk_image + ramdisk_size - 1,
287 relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
290 static void __init early_reserve_initrd(void)
292 /* Assume only end is not page aligned */
293 u64 ramdisk_image = get_ramdisk_image();
294 u64 ramdisk_size = get_ramdisk_size();
295 u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size);
297 if (!boot_params.hdr.type_of_loader ||
298 !ramdisk_image || !ramdisk_size)
299 return; /* No initrd provided by bootloader */
301 memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
304 static void __init reserve_initrd(void)
306 /* Assume only end is not page aligned */
307 u64 ramdisk_image = get_ramdisk_image();
308 u64 ramdisk_size = get_ramdisk_size();
309 u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size);
311 if (!boot_params.hdr.type_of_loader ||
312 !ramdisk_image || !ramdisk_size)
313 return; /* No initrd provided by bootloader */
317 printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
320 if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
321 PFN_DOWN(ramdisk_end))) {
322 /* All are mapped, easy case */
323 initrd_start = ramdisk_image + PAGE_OFFSET;
324 initrd_end = initrd_start + ramdisk_size;
330 memblock_phys_free(ramdisk_image, ramdisk_end - ramdisk_image);
334 static void __init early_reserve_initrd(void)
337 static void __init reserve_initrd(void)
340 #endif /* CONFIG_BLK_DEV_INITRD */
342 static void __init add_early_ima_buffer(u64 phys_addr)
345 struct ima_setup_data *data;
347 data = early_memremap(phys_addr + sizeof(struct setup_data), sizeof(*data));
349 pr_warn("setup: failed to memremap ima_setup_data entry\n");
354 memblock_reserve(data->addr, data->size);
355 ima_kexec_buffer_phys = data->addr;
356 ima_kexec_buffer_size = data->size;
359 early_memunmap(data, sizeof(*data));
361 pr_warn("Passed IMA kexec data, but CONFIG_IMA not set. Ignoring.\n");
365 #if defined(CONFIG_HAVE_IMA_KEXEC) && !defined(CONFIG_OF_FLATTREE)
366 int __init ima_free_kexec_buffer(void)
370 if (!ima_kexec_buffer_size)
373 rc = memblock_phys_free(ima_kexec_buffer_phys,
374 ima_kexec_buffer_size);
378 ima_kexec_buffer_phys = 0;
379 ima_kexec_buffer_size = 0;
384 int __init ima_get_kexec_buffer(void **addr, size_t *size)
386 if (!ima_kexec_buffer_size)
389 *addr = __va(ima_kexec_buffer_phys);
390 *size = ima_kexec_buffer_size;
396 static void __init parse_setup_data(void)
398 struct setup_data *data;
399 u64 pa_data, pa_next;
401 pa_data = boot_params.hdr.setup_data;
403 u32 data_len, data_type;
405 data = early_memremap(pa_data, sizeof(*data));
406 data_len = data->len + sizeof(struct setup_data);
407 data_type = data->type;
408 pa_next = data->next;
409 early_memunmap(data, sizeof(*data));
413 e820__memory_setup_extended(pa_data, data_len);
419 parse_efi_setup(pa_data, data_len);
422 add_early_ima_buffer(pa_data);
425 data = early_memremap(pa_data, data_len);
426 add_bootloader_randomness(data->data, data->len);
427 /* Zero seed for forward secrecy. */
428 memzero_explicit(data->data, data->len);
429 /* Zero length in case we find ourselves back here by accident. */
430 memzero_explicit(&data->len, sizeof(data->len));
431 early_memunmap(data, data_len);
440 static void __init memblock_x86_reserve_range_setup_data(void)
442 struct setup_indirect *indirect;
443 struct setup_data *data;
444 u64 pa_data, pa_next;
447 pa_data = boot_params.hdr.setup_data;
449 data = early_memremap(pa_data, sizeof(*data));
451 pr_warn("setup: failed to memremap setup_data entry\n");
456 pa_next = data->next;
458 memblock_reserve(pa_data, sizeof(*data) + data->len);
460 if (data->type == SETUP_INDIRECT) {
462 early_memunmap(data, sizeof(*data));
463 data = early_memremap(pa_data, len);
465 pr_warn("setup: failed to memremap indirect setup_data\n");
469 indirect = (struct setup_indirect *)data->data;
471 if (indirect->type != SETUP_INDIRECT)
472 memblock_reserve(indirect->addr, indirect->len);
476 early_memunmap(data, len);
481 * --------- Crashkernel reservation ------------------------------
484 /* 16M alignment for crash kernel regions */
485 #define CRASH_ALIGN SZ_16M
488 * Keep the crash kernel below this limit.
490 * Earlier 32-bits kernels would limit the kernel to the low 512 MB range
491 * due to mapping restrictions.
493 * 64-bit kdump kernels need to be restricted to be under 64 TB, which is
494 * the upper limit of system RAM in 4-level paging mode. Since the kdump
495 * jump could be from 5-level paging to 4-level paging, the jump will fail if
496 * the kernel is put above 64 TB, and during the 1st kernel bootup there's
497 * no good way to detect the paging mode of the target kernel which will be
498 * loaded for dumping.
501 # define CRASH_ADDR_LOW_MAX SZ_512M
502 # define CRASH_ADDR_HIGH_MAX SZ_512M
504 # define CRASH_ADDR_LOW_MAX SZ_4G
505 # define CRASH_ADDR_HIGH_MAX SZ_64T
508 static int __init reserve_crashkernel_low(void)
511 unsigned long long base, low_base = 0, low_size = 0;
512 unsigned long low_mem_limit;
515 low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX);
517 /* crashkernel=Y,low */
518 ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base);
521 * two parts from kernel/dma/swiotlb.c:
522 * -swiotlb size: user-specified with swiotlb= or default.
524 * -swiotlb overflow buffer: now hardcoded to 32k. We round it
525 * to 8M for other buffers that may need to stay low too. Also
526 * make sure we allocate enough extra low memory so that we
527 * don't run out of DMA buffers for 32-bit devices.
529 low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20);
531 /* passed with crashkernel=0,low ? */
536 low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
538 pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
539 (unsigned long)(low_size >> 20));
543 pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n",
544 (unsigned long)(low_size >> 20),
545 (unsigned long)(low_base >> 20),
546 (unsigned long)(low_mem_limit >> 20));
548 crashk_low_res.start = low_base;
549 crashk_low_res.end = low_base + low_size - 1;
550 insert_resource(&iomem_resource, &crashk_low_res);
555 static void __init reserve_crashkernel(void)
557 unsigned long long crash_size, crash_base, total_mem;
561 if (!IS_ENABLED(CONFIG_KEXEC_CORE))
564 total_mem = memblock_phys_mem_size();
567 ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base);
568 if (ret != 0 || crash_size <= 0) {
569 /* crashkernel=X,high */
570 ret = parse_crashkernel_high(boot_command_line, total_mem,
571 &crash_size, &crash_base);
572 if (ret != 0 || crash_size <= 0)
577 if (xen_pv_domain()) {
578 pr_info("Ignoring crashkernel for a Xen PV domain\n");
582 /* 0 means: find the address automatically */
585 * Set CRASH_ADDR_LOW_MAX upper bound for crash memory,
586 * crashkernel=x,high reserves memory over 4G, also allocates
587 * 256M extra low memory for DMA buffers and swiotlb.
588 * But the extra memory is not required for all machines.
589 * So try low memory first and fall back to high memory
590 * unless "crashkernel=size[KMG],high" is specified.
593 crash_base = memblock_phys_alloc_range(crash_size,
594 CRASH_ALIGN, CRASH_ALIGN,
597 crash_base = memblock_phys_alloc_range(crash_size,
598 CRASH_ALIGN, CRASH_ALIGN,
599 CRASH_ADDR_HIGH_MAX);
601 pr_info("crashkernel reservation failed - No suitable area found.\n");
605 unsigned long long start;
607 start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
608 crash_base + crash_size);
609 if (start != crash_base) {
610 pr_info("crashkernel reservation failed - memory is in use.\n");
615 if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) {
616 memblock_phys_free(crash_base, crash_size);
620 pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
621 (unsigned long)(crash_size >> 20),
622 (unsigned long)(crash_base >> 20),
623 (unsigned long)(total_mem >> 20));
625 crashk_res.start = crash_base;
626 crashk_res.end = crash_base + crash_size - 1;
627 insert_resource(&iomem_resource, &crashk_res);
630 static struct resource standard_io_resources[] = {
631 { .name = "dma1", .start = 0x00, .end = 0x1f,
632 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
633 { .name = "pic1", .start = 0x20, .end = 0x21,
634 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
635 { .name = "timer0", .start = 0x40, .end = 0x43,
636 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
637 { .name = "timer1", .start = 0x50, .end = 0x53,
638 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
639 { .name = "keyboard", .start = 0x60, .end = 0x60,
640 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
641 { .name = "keyboard", .start = 0x64, .end = 0x64,
642 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
643 { .name = "dma page reg", .start = 0x80, .end = 0x8f,
644 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
645 { .name = "pic2", .start = 0xa0, .end = 0xa1,
646 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
647 { .name = "dma2", .start = 0xc0, .end = 0xdf,
648 .flags = IORESOURCE_BUSY | IORESOURCE_IO },
649 { .name = "fpu", .start = 0xf0, .end = 0xff,
650 .flags = IORESOURCE_BUSY | IORESOURCE_IO }
653 void __init reserve_standard_io_resources(void)
657 /* request I/O space for devices used on all i[345]86 PCs */
658 for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
659 request_resource(&ioport_resource, &standard_io_resources[i]);
663 static bool __init snb_gfx_workaround_needed(void)
668 static const __initconst u16 snb_ids[] = {
678 /* Assume no if something weird is going on with PCI */
679 if (!early_pci_allowed())
682 vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
683 if (vendor != 0x8086)
686 devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
687 for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
688 if (devid == snb_ids[i])
696 * Sandy Bridge graphics has trouble with certain ranges, exclude
697 * them from allocation.
699 static void __init trim_snb_memory(void)
701 static const __initconst unsigned long bad_pages[] = {
710 if (!snb_gfx_workaround_needed())
713 printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
716 * SandyBridge integrated graphics devices have a bug that prevents
717 * them from accessing certain memory ranges, namely anything below
718 * 1M and in the pages listed in bad_pages[] above.
720 * To avoid these pages being ever accessed by SNB gfx devices reserve
721 * bad_pages that have not already been reserved at boot time.
722 * All memory below the 1 MB mark is anyway reserved later during
723 * setup_arch(), so there is no need to reserve it here.
726 for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
727 if (memblock_reserve(bad_pages[i], PAGE_SIZE))
728 printk(KERN_WARNING "failed to reserve 0x%08lx\n",
733 static void __init trim_bios_range(void)
736 * A special case is the first 4Kb of memory;
737 * This is a BIOS owned area, not kernel ram, but generally
738 * not listed as such in the E820 table.
740 * This typically reserves additional memory (64KiB by default)
741 * since some BIOSes are known to corrupt low memory. See the
742 * Kconfig help text for X86_RESERVE_LOW.
744 e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
747 * special case: Some BIOSes report the PC BIOS
748 * area (640Kb -> 1Mb) as RAM even though it is not.
751 e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
753 e820__update_table(e820_table);
756 /* called before trim_bios_range() to spare extra sanitize */
757 static void __init e820_add_kernel_range(void)
759 u64 start = __pa_symbol(_text);
760 u64 size = __pa_symbol(_end) - start;
763 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
764 * attempt to fix it by adding the range. We may have a confused BIOS,
765 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
766 * exclude kernel range. If we really are running on top non-RAM,
767 * we will crash later anyways.
769 if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
772 pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
773 e820__range_remove(start, size, E820_TYPE_RAM, 0);
774 e820__range_add(start, size, E820_TYPE_RAM);
777 static void __init early_reserve_memory(void)
780 * Reserve the memory occupied by the kernel between _text and
781 * __end_of_kernel_reserve symbols. Any kernel sections after the
782 * __end_of_kernel_reserve symbol must be explicitly reserved with a
783 * separate memblock_reserve() or they will be discarded.
785 memblock_reserve(__pa_symbol(_text),
786 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
789 * The first 4Kb of memory is a BIOS owned area, but generally it is
790 * not listed as such in the E820 table.
792 * Reserve the first 64K of memory since some BIOSes are known to
793 * corrupt low memory. After the real mode trampoline is allocated the
794 * rest of the memory below 640k is reserved.
796 * In addition, make sure page 0 is always reserved because on
797 * systems with L1TF its contents can be leaked to user processes.
799 memblock_reserve(0, SZ_64K);
801 early_reserve_initrd();
803 memblock_x86_reserve_range_setup_data();
805 reserve_ibft_region();
806 reserve_bios_regions();
811 * Dump out kernel offset information on panic.
814 dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
816 if (kaslr_enabled()) {
817 pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
823 pr_emerg("Kernel Offset: disabled\n");
829 void x86_configure_nx(void)
831 if (boot_cpu_has(X86_FEATURE_NX))
832 __supported_pte_mask |= _PAGE_NX;
834 __supported_pte_mask &= ~_PAGE_NX;
837 static void __init x86_report_nx(void)
839 if (!boot_cpu_has(X86_FEATURE_NX)) {
840 printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
841 "missing in CPU!\n");
843 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
844 printk(KERN_INFO "NX (Execute Disable) protection: active\n");
846 /* 32bit non-PAE kernel, NX cannot be used */
847 printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
848 "cannot be enabled: non-PAE kernel!\n");
854 * Determine if we were loaded by an EFI loader. If so, then we have also been
855 * passed the efi memmap, systab, etc., so we should use these data structures
856 * for initialization. Note, the efi init code path is determined by the
857 * global efi_enabled. This allows the same kernel image to be used on existing
858 * systems (with a traditional BIOS) as well as on EFI systems.
861 * setup_arch - architecture-specific boot-time initializations
863 * Note: On x86_64, fixmaps are ready for use even before this is called.
866 void __init setup_arch(char **cmdline_p)
869 memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
872 * copy kernel address range established so far and switch
873 * to the proper swapper page table
875 clone_pgd_range(swapper_pg_dir + KERNEL_PGD_BOUNDARY,
876 initial_page_table + KERNEL_PGD_BOUNDARY,
879 load_cr3(swapper_pg_dir);
881 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
882 * a cr3 based tlb flush, so the following __flush_tlb_all()
883 * will not flush anything because the CPU quirk which clears
884 * X86_FEATURE_PGE has not been invoked yet. Though due to the
885 * load_cr3() above the TLB has been flushed already. The
886 * quirk is invoked before subsequent calls to __flush_tlb_all()
887 * so proper operation is guaranteed.
891 printk(KERN_INFO "Command line: %s\n", boot_command_line);
892 boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
896 * If we have OLPC OFW, we might end up relocating the fixmap due to
897 * reserve_top(), so do this before touching the ioremap area.
901 idt_setup_early_traps();
905 early_ioremap_init();
907 setup_olpc_ofw_pgd();
909 ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
910 screen_info = boot_params.screen_info;
911 edid_info = boot_params.edid_info;
913 apm_info.bios = boot_params.apm_bios_info;
914 ist_info = boot_params.ist_info;
916 saved_video_mode = boot_params.hdr.vid_mode;
917 bootloader_type = boot_params.hdr.type_of_loader;
918 if ((bootloader_type >> 4) == 0xe) {
919 bootloader_type &= 0xf;
920 bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
922 bootloader_version = bootloader_type & 0xf;
923 bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
925 #ifdef CONFIG_BLK_DEV_RAM
926 rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
929 if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
930 EFI32_LOADER_SIGNATURE, 4)) {
931 set_bit(EFI_BOOT, &efi.flags);
932 } else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
933 EFI64_LOADER_SIGNATURE, 4)) {
934 set_bit(EFI_BOOT, &efi.flags);
935 set_bit(EFI_64BIT, &efi.flags);
939 x86_init.oem.arch_setup();
942 * Do some memory reservations *before* memory is added to memblock, so
943 * memblock allocations won't overwrite it.
945 * After this point, everything still needed from the boot loader or
946 * firmware or kernel text should be early reserved or marked not RAM in
947 * e820. All other memory is free game.
949 * This call needs to happen before e820__memory_setup() which calls the
950 * xen_memory_setup() on Xen dom0 which relies on the fact that those
951 * early reservations have happened already.
953 early_reserve_memory();
955 iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
956 e820__memory_setup();
961 if (!boot_params.hdr.root_flags)
962 root_mountflags &= ~MS_RDONLY;
963 setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
965 code_resource.start = __pa_symbol(_text);
966 code_resource.end = __pa_symbol(_etext)-1;
967 rodata_resource.start = __pa_symbol(__start_rodata);
968 rodata_resource.end = __pa_symbol(__end_rodata)-1;
969 data_resource.start = __pa_symbol(_sdata);
970 data_resource.end = __pa_symbol(_edata)-1;
971 bss_resource.start = __pa_symbol(__bss_start);
972 bss_resource.end = __pa_symbol(__bss_stop)-1;
974 #ifdef CONFIG_CMDLINE_BOOL
975 #ifdef CONFIG_CMDLINE_OVERRIDE
976 strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
978 if (builtin_cmdline[0]) {
979 /* append boot loader cmdline to builtin */
980 strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
981 strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
982 strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
987 strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
988 *cmdline_p = command_line;
991 * x86_configure_nx() is called before parse_early_param() to detect
992 * whether hardware doesn't support NX (so that the early EHCI debug
993 * console setup can safely call set_fixmap()).
999 if (efi_enabled(EFI_BOOT))
1000 efi_memblock_x86_reserve_range();
1002 #ifdef CONFIG_MEMORY_HOTPLUG
1004 * Memory used by the kernel cannot be hot-removed because Linux
1005 * cannot migrate the kernel pages. When memory hotplug is
1006 * enabled, we should prevent memblock from allocating memory
1009 * ACPI SRAT records all hotpluggable memory ranges. But before
1010 * SRAT is parsed, we don't know about it.
1012 * The kernel image is loaded into memory at very early time. We
1013 * cannot prevent this anyway. So on NUMA system, we set any
1014 * node the kernel resides in as un-hotpluggable.
1016 * Since on modern servers, one node could have double-digit
1017 * gigabytes memory, we can assume the memory around the kernel
1018 * image is also un-hotpluggable. So before SRAT is parsed, just
1019 * allocate memory near the kernel image to try the best to keep
1020 * the kernel away from hotpluggable memory.
1022 if (movable_node_is_enabled())
1023 memblock_set_bottom_up(true);
1028 if (acpi_mps_check()) {
1029 #ifdef CONFIG_X86_LOCAL_APIC
1032 setup_clear_cpu_cap(X86_FEATURE_APIC);
1035 e820__reserve_setup_data();
1036 e820__finish_early_params();
1038 if (efi_enabled(EFI_BOOT))
1044 * VMware detection requires dmi to be available, so this
1045 * needs to be done after dmi_setup(), for the boot CPU.
1047 init_hypervisor_platform();
1050 x86_init.resources.probe_roms();
1052 /* after parse_early_param, so could debug it */
1053 insert_resource(&iomem_resource, &code_resource);
1054 insert_resource(&iomem_resource, &rodata_resource);
1055 insert_resource(&iomem_resource, &data_resource);
1056 insert_resource(&iomem_resource, &bss_resource);
1058 e820_add_kernel_range();
1060 #ifdef CONFIG_X86_32
1061 if (ppro_with_ram_bug()) {
1062 e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
1063 E820_TYPE_RESERVED);
1064 e820__update_table(e820_table);
1065 printk(KERN_INFO "fixed physical RAM map:\n");
1066 e820__print_table("bad_ppro");
1069 early_gart_iommu_check();
1073 * partially used pages are not usable - thus
1074 * we are rounding upwards:
1076 max_pfn = e820__end_of_ram_pfn();
1078 /* update e820 for memory not covered by WB MTRRs */
1080 if (mtrr_trim_uncached_memory(max_pfn))
1081 max_pfn = e820__end_of_ram_pfn();
1083 max_possible_pfn = max_pfn;
1086 * Define random base addresses for memory sections after max_pfn is
1087 * defined and before each memory section base is used.
1089 kernel_randomize_memory();
1091 #ifdef CONFIG_X86_32
1092 /* max_low_pfn get updated here */
1093 find_low_pfn_range();
1097 /* How many end-of-memory variables you have, grandma! */
1098 /* need this before calling reserve_initrd */
1099 if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
1100 max_low_pfn = e820__end_of_low_ram_pfn();
1102 max_low_pfn = max_pfn;
1104 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
1108 * Find and reserve possible boot-time SMP configuration:
1112 early_alloc_pgt_buf();
1115 * Need to conclude brk, before e820__memblock_setup()
1116 * it could use memblock_find_in_range, could overlap with
1123 memblock_set_current_limit(ISA_END_ADDRESS);
1124 e820__memblock_setup();
1127 * Needs to run after memblock setup because it needs the physical
1135 efi_mokvar_table_init();
1138 * The EFI specification says that boot service code won't be
1139 * called after ExitBootServices(). This is, in fact, a lie.
1141 efi_reserve_boot_services();
1143 /* preallocate 4k for mptable mpc */
1144 e820__memblock_alloc_reserved_mpc_new();
1146 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1147 setup_bios_corruption_check();
1150 #ifdef CONFIG_X86_32
1151 printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1152 (max_pfn_mapped<<PAGE_SHIFT) - 1);
1156 * Find free memory for the real mode trampoline and place it there. If
1157 * there is not enough free memory under 1M, on EFI-enabled systems
1158 * there will be additional attempt to reclaim the memory for the real
1159 * mode trampoline at efi_free_boot_services().
1161 * Unconditionally reserve the entire first 1M of RAM because BIOSes
1162 * are known to corrupt low memory and several hundred kilobytes are not
1163 * worth complex detection what memory gets clobbered. Windows does the
1164 * same thing for very similar reasons.
1166 * Moreover, on machines with SandyBridge graphics or in setups that use
1167 * crashkernel the entire 1M is reserved anyway.
1169 x86_platform.realmode_reserve();
1173 idt_setup_early_pf();
1176 * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features)
1177 * with the current CR4 value. This may not be necessary, but
1178 * auditing all the early-boot CR4 manipulation would be needed to
1181 * Mask off features that don't work outside long mode (just
1184 mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE;
1186 memblock_set_current_limit(get_max_mapped());
1189 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1192 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1193 if (init_ohci1394_dma_early)
1194 init_ohci1394_dma_on_all_controllers();
1196 /* Allocate bigger log buffer */
1199 if (efi_enabled(EFI_BOOT)) {
1200 switch (boot_params.secure_boot) {
1201 case efi_secureboot_mode_disabled:
1202 pr_info("Secure boot disabled\n");
1204 case efi_secureboot_mode_enabled:
1205 pr_info("Secure boot enabled\n");
1208 pr_info("Secure boot could not be determined\n");
1215 acpi_table_upgrade();
1216 /* Look for ACPI tables and reserve memory occupied by them. */
1217 acpi_boot_table_init();
1223 early_platform_quirks();
1225 early_acpi_boot_init();
1228 dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1230 if (boot_cpu_has(X86_FEATURE_GBPAGES))
1231 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1234 * Reserve memory for crash kernel after SRAT is parsed so that it
1235 * won't consume hotpluggable memory.
1237 reserve_crashkernel();
1239 memblock_find_dma_reserve();
1241 if (!early_xdbc_setup_hardware())
1242 early_xdbc_register_console();
1244 x86_init.paging.pagetable_init();
1249 * Sync back kernel address range.
1251 * FIXME: Can the later sync in setup_cpu_entry_areas() replace
1254 sync_initial_page_table();
1260 generic_apic_probe();
1265 * Read APIC and some other early information from ACPI tables.
1271 * get boot-time SMP configuration:
1276 * Systems w/o ACPI and mptables might not have it mapped the local
1277 * APIC yet, but prefill_possible_map() might need to access it.
1279 init_apic_mappings();
1281 prefill_possible_map();
1286 io_apic_init_mappings();
1288 x86_init.hyper.guest_late_init();
1290 e820__reserve_resources();
1291 e820__register_nosave_regions(max_pfn);
1293 x86_init.resources.reserve_resources();
1295 e820__setup_pci_gap();
1298 #if defined(CONFIG_VGA_CONSOLE)
1299 if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1300 conswitchp = &vga_con;
1303 x86_init.oem.banner();
1305 x86_init.timers.wallclock_init();
1308 * This needs to run before setup_local_APIC() which soft-disables the
1309 * local APIC temporarily and that masks the thermal LVT interrupt,
1310 * leading to softlockups on machines which have configured SMI
1311 * interrupt delivery.
1317 register_refined_jiffies(CLOCK_TICK_RATE);
1320 if (efi_enabled(EFI_BOOT))
1321 efi_apply_memmap_quirks();
1327 #ifdef CONFIG_X86_32
1329 static struct resource video_ram_resource = {
1330 .name = "Video RAM area",
1333 .flags = IORESOURCE_BUSY | IORESOURCE_MEM
1336 void __init i386_reserve_resources(void)
1338 request_resource(&iomem_resource, &video_ram_resource);
1339 reserve_standard_io_resources();
1342 #endif /* CONFIG_X86_32 */
1344 static struct notifier_block kernel_offset_notifier = {
1345 .notifier_call = dump_kernel_offset
1348 static int __init register_kernel_offset_dumper(void)
1350 atomic_notifier_chain_register(&panic_notifier_list,
1351 &kernel_offset_notifier);
1354 __initcall(register_kernel_offset_dumper);