diff options
Diffstat (limited to 'arch/x86/kernel/setup.c')
| -rw-r--r-- | arch/x86/kernel/setup.c | 1347 |
1 files changed, 1347 insertions, 0 deletions
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c new file mode 100644 index 0000000000..b098b1fa24 --- /dev/null +++ b/arch/x86/kernel/setup.c @@ -0,0 +1,1347 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 1995 Linus Torvalds + * + * This file contains the setup_arch() code, which handles the architecture-dependent + * parts of early kernel initialization. + */ +#include <linux/acpi.h> +#include <linux/console.h> +#include <linux/crash_dump.h> +#include <linux/dma-map-ops.h> +#include <linux/dmi.h> +#include <linux/efi.h> +#include <linux/ima.h> +#include <linux/init_ohci1394_dma.h> +#include <linux/initrd.h> +#include <linux/iscsi_ibft.h> +#include <linux/memblock.h> +#include <linux/panic_notifier.h> +#include <linux/pci.h> +#include <linux/root_dev.h> +#include <linux/hugetlb.h> +#include <linux/tboot.h> +#include <linux/usb/xhci-dbgp.h> +#include <linux/static_call.h> +#include <linux/swiotlb.h> +#include <linux/random.h> + +#include <uapi/linux/mount.h> + +#include <xen/xen.h> + +#include <asm/apic.h> +#include <asm/efi.h> +#include <asm/numa.h> +#include <asm/bios_ebda.h> +#include <asm/bugs.h> +#include <asm/cacheinfo.h> +#include <asm/cpu.h> +#include <asm/efi.h> +#include <asm/gart.h> +#include <asm/hypervisor.h> +#include <asm/io_apic.h> +#include <asm/kasan.h> +#include <asm/kaslr.h> +#include <asm/mce.h> +#include <asm/memtype.h> +#include <asm/mtrr.h> +#include <asm/realmode.h> +#include <asm/olpc_ofw.h> +#include <asm/pci-direct.h> +#include <asm/prom.h> +#include <asm/proto.h> +#include <asm/thermal.h> +#include <asm/unwind.h> +#include <asm/vsyscall.h> +#include <linux/vmalloc.h> + +/* + * max_low_pfn_mapped: highest directly mapped pfn < 4 GB + * max_pfn_mapped: highest directly mapped pfn > 4 GB + * + * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are + * represented by pfn_mapped[]. + */ +unsigned long max_low_pfn_mapped; +unsigned long max_pfn_mapped; + +#ifdef CONFIG_DMI +RESERVE_BRK(dmi_alloc, 65536); +#endif + + +unsigned long _brk_start = (unsigned long)__brk_base; +unsigned long _brk_end = (unsigned long)__brk_base; + +struct boot_params boot_params; + +/* + * These are the four main kernel memory regions, we put them into + * the resource tree so that kdump tools and other debugging tools + * recover it: + */ + +static struct resource rodata_resource = { + .name = "Kernel rodata", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM +}; + +static struct resource data_resource = { + .name = "Kernel data", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM +}; + +static struct resource code_resource = { + .name = "Kernel code", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM +}; + +static struct resource bss_resource = { + .name = "Kernel bss", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM +}; + + +#ifdef CONFIG_X86_32 +/* CPU data as detected by the assembly code in head_32.S */ +struct cpuinfo_x86 new_cpu_data; + +struct apm_info apm_info; +EXPORT_SYMBOL(apm_info); + +#if defined(CONFIG_X86_SPEEDSTEP_SMI) || \ + defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE) +struct ist_info ist_info; +EXPORT_SYMBOL(ist_info); +#else +struct ist_info ist_info; +#endif + +#endif + +struct cpuinfo_x86 boot_cpu_data __read_mostly; +EXPORT_SYMBOL(boot_cpu_data); + +#if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64) +__visible unsigned long mmu_cr4_features __ro_after_init; +#else +__visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE; +#endif + +#ifdef CONFIG_IMA +static phys_addr_t ima_kexec_buffer_phys; +static size_t ima_kexec_buffer_size; +#endif + +/* Boot loader ID and version as integers, for the benefit of proc_dointvec */ +int bootloader_type, bootloader_version; + +/* + * Setup options + */ +struct screen_info screen_info; +EXPORT_SYMBOL(screen_info); +struct edid_info edid_info; +EXPORT_SYMBOL_GPL(edid_info); + +extern int root_mountflags; + +unsigned long saved_video_mode; + +#define RAMDISK_IMAGE_START_MASK 0x07FF +#define RAMDISK_PROMPT_FLAG 0x8000 +#define RAMDISK_LOAD_FLAG 0x4000 + +static char __initdata command_line[COMMAND_LINE_SIZE]; +#ifdef CONFIG_CMDLINE_BOOL +static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE; +#endif + +#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE) +struct edd edd; +#ifdef CONFIG_EDD_MODULE +EXPORT_SYMBOL(edd); +#endif +/** + * copy_edd() - Copy the BIOS EDD information + * from boot_params into a safe place. + * + */ +static inline void __init copy_edd(void) +{ + memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer, + sizeof(edd.mbr_signature)); + memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info)); + edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries; + edd.edd_info_nr = boot_params.eddbuf_entries; +} +#else +static inline void __init copy_edd(void) +{ +} +#endif + +void * __init extend_brk(size_t size, size_t align) +{ + size_t mask = align - 1; + void *ret; + + BUG_ON(_brk_start == 0); + BUG_ON(align & mask); + + _brk_end = (_brk_end + mask) & ~mask; + BUG_ON((char *)(_brk_end + size) > __brk_limit); + + ret = (void *)_brk_end; + _brk_end += size; + + memset(ret, 0, size); + + return ret; +} + +#ifdef CONFIG_X86_32 +static void __init cleanup_highmap(void) +{ +} +#endif + +static void __init reserve_brk(void) +{ + if (_brk_end > _brk_start) + memblock_reserve(__pa_symbol(_brk_start), + _brk_end - _brk_start); + + /* Mark brk area as locked down and no longer taking any + new allocations */ + _brk_start = 0; +} + +u64 relocated_ramdisk; + +#ifdef CONFIG_BLK_DEV_INITRD + +static u64 __init get_ramdisk_image(void) +{ + u64 ramdisk_image = boot_params.hdr.ramdisk_image; + + ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32; + + if (ramdisk_image == 0) + ramdisk_image = phys_initrd_start; + + return ramdisk_image; +} +static u64 __init get_ramdisk_size(void) +{ + u64 ramdisk_size = boot_params.hdr.ramdisk_size; + + ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32; + + if (ramdisk_size == 0) + ramdisk_size = phys_initrd_size; + + return ramdisk_size; +} + +static void __init relocate_initrd(void) +{ + /* Assume only end is not page aligned */ + u64 ramdisk_image = get_ramdisk_image(); + u64 ramdisk_size = get_ramdisk_size(); + u64 area_size = PAGE_ALIGN(ramdisk_size); + + /* We need to move the initrd down into directly mapped mem */ + relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0, + PFN_PHYS(max_pfn_mapped)); + if (!relocated_ramdisk) + panic("Cannot find place for new RAMDISK of size %lld\n", + ramdisk_size); + + initrd_start = relocated_ramdisk + PAGE_OFFSET; + initrd_end = initrd_start + ramdisk_size; + printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n", + relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1); + + copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size); + + printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to" + " [mem %#010llx-%#010llx]\n", + ramdisk_image, ramdisk_image + ramdisk_size - 1, + relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1); +} + +static void __init early_reserve_initrd(void) +{ + /* Assume only end is not page aligned */ + u64 ramdisk_image = get_ramdisk_image(); + u64 ramdisk_size = get_ramdisk_size(); + u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size); + + if (!boot_params.hdr.type_of_loader || + !ramdisk_image || !ramdisk_size) + return; /* No initrd provided by bootloader */ + + memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image); +} + +static void __init reserve_initrd(void) +{ + /* Assume only end is not page aligned */ + u64 ramdisk_image = get_ramdisk_image(); + u64 ramdisk_size = get_ramdisk_size(); + u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size); + + if (!boot_params.hdr.type_of_loader || + !ramdisk_image || !ramdisk_size) + return; /* No initrd provided by bootloader */ + + initrd_start = 0; + + printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image, + ramdisk_end - 1); + + if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image), + PFN_DOWN(ramdisk_end))) { + /* All are mapped, easy case */ + initrd_start = ramdisk_image + PAGE_OFFSET; + initrd_end = initrd_start + ramdisk_size; + return; + } + + relocate_initrd(); + + memblock_phys_free(ramdisk_image, ramdisk_end - ramdisk_image); +} + +#else +static void __init early_reserve_initrd(void) +{ +} +static void __init reserve_initrd(void) +{ +} +#endif /* CONFIG_BLK_DEV_INITRD */ + +static void __init add_early_ima_buffer(u64 phys_addr) +{ +#ifdef CONFIG_IMA + struct ima_setup_data *data; + + data = early_memremap(phys_addr + sizeof(struct setup_data), sizeof(*data)); + if (!data) { + pr_warn("setup: failed to memremap ima_setup_data entry\n"); + return; + } + + if (data->size) { + memblock_reserve(data->addr, data->size); + ima_kexec_buffer_phys = data->addr; + ima_kexec_buffer_size = data->size; + } + + early_memunmap(data, sizeof(*data)); +#else + pr_warn("Passed IMA kexec data, but CONFIG_IMA not set. Ignoring.\n"); +#endif +} + +#if defined(CONFIG_HAVE_IMA_KEXEC) && !defined(CONFIG_OF_FLATTREE) +int __init ima_free_kexec_buffer(void) +{ + if (!ima_kexec_buffer_size) + return -ENOENT; + + memblock_free_late(ima_kexec_buffer_phys, + ima_kexec_buffer_size); + + ima_kexec_buffer_phys = 0; + ima_kexec_buffer_size = 0; + + return 0; +} + +int __init ima_get_kexec_buffer(void **addr, size_t *size) +{ + if (!ima_kexec_buffer_size) + return -ENOENT; + + *addr = __va(ima_kexec_buffer_phys); + *size = ima_kexec_buffer_size; + + return 0; +} +#endif + +static void __init parse_setup_data(void) +{ + struct setup_data *data; + u64 pa_data, pa_next; + + pa_data = boot_params.hdr.setup_data; + while (pa_data) { + u32 data_len, data_type; + + data = early_memremap(pa_data, sizeof(*data)); + data_len = data->len + sizeof(struct setup_data); + data_type = data->type; + pa_next = data->next; + early_memunmap(data, sizeof(*data)); + + switch (data_type) { + case SETUP_E820_EXT: + e820__memory_setup_extended(pa_data, data_len); + break; + case SETUP_DTB: + add_dtb(pa_data); + break; + case SETUP_EFI: + parse_efi_setup(pa_data, data_len); + break; + case SETUP_IMA: + add_early_ima_buffer(pa_data); + break; + case SETUP_RNG_SEED: + data = early_memremap(pa_data, data_len); + add_bootloader_randomness(data->data, data->len); + /* Zero seed for forward secrecy. */ + memzero_explicit(data->data, data->len); + /* Zero length in case we find ourselves back here by accident. */ + memzero_explicit(&data->len, sizeof(data->len)); + early_memunmap(data, data_len); + break; + default: + break; + } + pa_data = pa_next; + } +} + +static void __init memblock_x86_reserve_range_setup_data(void) +{ + struct setup_indirect *indirect; + struct setup_data *data; + u64 pa_data, pa_next; + u32 len; + + pa_data = boot_params.hdr.setup_data; + while (pa_data) { + data = early_memremap(pa_data, sizeof(*data)); + if (!data) { + pr_warn("setup: failed to memremap setup_data entry\n"); + return; + } + + len = sizeof(*data); + pa_next = data->next; + + memblock_reserve(pa_data, sizeof(*data) + data->len); + + if (data->type == SETUP_INDIRECT) { + len += data->len; + early_memunmap(data, sizeof(*data)); + data = early_memremap(pa_data, len); + if (!data) { + pr_warn("setup: failed to memremap indirect setup_data\n"); + return; + } + + indirect = (struct setup_indirect *)data->data; + + if (indirect->type != SETUP_INDIRECT) + memblock_reserve(indirect->addr, indirect->len); + } + + pa_data = pa_next; + early_memunmap(data, len); + } +} + +/* + * --------- Crashkernel reservation ------------------------------ + */ + +/* 16M alignment for crash kernel regions */ +#define CRASH_ALIGN SZ_16M + +/* + * Keep the crash kernel below this limit. + * + * Earlier 32-bits kernels would limit the kernel to the low 512 MB range + * due to mapping restrictions. + * + * 64-bit kdump kernels need to be restricted to be under 64 TB, which is + * the upper limit of system RAM in 4-level paging mode. Since the kdump + * jump could be from 5-level paging to 4-level paging, the jump will fail if + * the kernel is put above 64 TB, and during the 1st kernel bootup there's + * no good way to detect the paging mode of the target kernel which will be + * loaded for dumping. + */ +#ifdef CONFIG_X86_32 +# define CRASH_ADDR_LOW_MAX SZ_512M +# define CRASH_ADDR_HIGH_MAX SZ_512M +#else +# define CRASH_ADDR_LOW_MAX SZ_4G +# define CRASH_ADDR_HIGH_MAX SZ_64T +#endif + +static int __init reserve_crashkernel_low(void) +{ +#ifdef CONFIG_X86_64 + unsigned long long base, low_base = 0, low_size = 0; + unsigned long low_mem_limit; + int ret; + + low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX); + + /* crashkernel=Y,low */ + ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base); + if (ret) { + /* + * two parts from kernel/dma/swiotlb.c: + * -swiotlb size: user-specified with swiotlb= or default. + * + * -swiotlb overflow buffer: now hardcoded to 32k. We round it + * to 8M for other buffers that may need to stay low too. Also + * make sure we allocate enough extra low memory so that we + * don't run out of DMA buffers for 32-bit devices. + */ + low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20); + } else { + /* passed with crashkernel=0,low ? */ + if (!low_size) + return 0; + } + + low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX); + if (!low_base) { + pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n", + (unsigned long)(low_size >> 20)); + return -ENOMEM; + } + + pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n", + (unsigned long)(low_size >> 20), + (unsigned long)(low_base >> 20), + (unsigned long)(low_mem_limit >> 20)); + + crashk_low_res.start = low_base; + crashk_low_res.end = low_base + low_size - 1; + insert_resource(&iomem_resource, &crashk_low_res); +#endif + return 0; +} + +static void __init reserve_crashkernel(void) +{ + unsigned long long crash_size, crash_base, total_mem; + bool high = false; + int ret; + + if (!IS_ENABLED(CONFIG_KEXEC_CORE)) + return; + + total_mem = memblock_phys_mem_size(); + + /* crashkernel=XM */ + ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base); + if (ret != 0 || crash_size <= 0) { + /* crashkernel=X,high */ + ret = parse_crashkernel_high(boot_command_line, total_mem, + &crash_size, &crash_base); + if (ret != 0 || crash_size <= 0) + return; + high = true; + } + + if (xen_pv_domain()) { + pr_info("Ignoring crashkernel for a Xen PV domain\n"); + return; + } + + /* 0 means: find the address automatically */ + if (!crash_base) { + /* + * Set CRASH_ADDR_LOW_MAX upper bound for crash memory, + * crashkernel=x,high reserves memory over 4G, also allocates + * 256M extra low memory for DMA buffers and swiotlb. + * But the extra memory is not required for all machines. + * So try low memory first and fall back to high memory + * unless "crashkernel=size[KMG],high" is specified. + */ + if (!high) + crash_base = memblock_phys_alloc_range(crash_size, + CRASH_ALIGN, CRASH_ALIGN, + CRASH_ADDR_LOW_MAX); + if (!crash_base) + crash_base = memblock_phys_alloc_range(crash_size, + CRASH_ALIGN, CRASH_ALIGN, + CRASH_ADDR_HIGH_MAX); + if (!crash_base) { + pr_info("crashkernel reservation failed - No suitable area found.\n"); + return; + } + } else { + unsigned long long start; + + start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base, + crash_base + crash_size); + if (start != crash_base) { + pr_info("crashkernel reservation failed - memory is in use.\n"); + return; + } + } + + if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) { + memblock_phys_free(crash_base, crash_size); + return; + } + + pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n", + (unsigned long)(crash_size >> 20), + (unsigned long)(crash_base >> 20), + (unsigned long)(total_mem >> 20)); + + crashk_res.start = crash_base; + crashk_res.end = crash_base + crash_size - 1; + insert_resource(&iomem_resource, &crashk_res); +} + +static struct resource standard_io_resources[] = { + { .name = "dma1", .start = 0x00, .end = 0x1f, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "pic1", .start = 0x20, .end = 0x21, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "timer0", .start = 0x40, .end = 0x43, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "timer1", .start = 0x50, .end = 0x53, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "keyboard", .start = 0x60, .end = 0x60, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "keyboard", .start = 0x64, .end = 0x64, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "dma page reg", .start = 0x80, .end = 0x8f, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "pic2", .start = 0xa0, .end = 0xa1, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "dma2", .start = 0xc0, .end = 0xdf, + .flags = IORESOURCE_BUSY | IORESOURCE_IO }, + { .name = "fpu", .start = 0xf0, .end = 0xff, + .flags = IORESOURCE_BUSY | IORESOURCE_IO } +}; + +void __init reserve_standard_io_resources(void) +{ + int i; + + /* request I/O space for devices used on all i[345]86 PCs */ + for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++) + request_resource(&ioport_resource, &standard_io_resources[i]); + +} + +static bool __init snb_gfx_workaround_needed(void) +{ +#ifdef CONFIG_PCI + int i; + u16 vendor, devid; + static const __initconst u16 snb_ids[] = { + 0x0102, + 0x0112, + 0x0122, + 0x0106, + 0x0116, + 0x0126, + 0x010a, + }; + + /* Assume no if something weird is going on with PCI */ + if (!early_pci_allowed()) + return false; + + vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID); + if (vendor != 0x8086) + return false; + + devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID); + for (i = 0; i < ARRAY_SIZE(snb_ids); i++) + if (devid == snb_ids[i]) + return true; +#endif + + return false; +} + +/* + * Sandy Bridge graphics has trouble with certain ranges, exclude + * them from allocation. + */ +static void __init trim_snb_memory(void) +{ + static const __initconst unsigned long bad_pages[] = { + 0x20050000, + 0x20110000, + 0x20130000, + 0x20138000, + 0x40004000, + }; + int i; + + if (!snb_gfx_workaround_needed()) + return; + + printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n"); + + /* + * SandyBridge integrated graphics devices have a bug that prevents + * them from accessing certain memory ranges, namely anything below + * 1M and in the pages listed in bad_pages[] above. + * + * To avoid these pages being ever accessed by SNB gfx devices reserve + * bad_pages that have not already been reserved at boot time. + * All memory below the 1 MB mark is anyway reserved later during + * setup_arch(), so there is no need to reserve it here. + */ + + for (i = 0; i < ARRAY_SIZE(bad_pages); i++) { + if (memblock_reserve(bad_pages[i], PAGE_SIZE)) + printk(KERN_WARNING "failed to reserve 0x%08lx\n", + bad_pages[i]); + } +} + +static void __init trim_bios_range(void) +{ + /* + * A special case is the first 4Kb of memory; + * This is a BIOS owned area, not kernel ram, but generally + * not listed as such in the E820 table. + * + * This typically reserves additional memory (64KiB by default) + * since some BIOSes are known to corrupt low memory. See the + * Kconfig help text for X86_RESERVE_LOW. + */ + e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED); + + /* + * special case: Some BIOSes report the PC BIOS + * area (640Kb -> 1Mb) as RAM even though it is not. + * take them out. + */ + e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1); + + e820__update_table(e820_table); +} + +/* called before trim_bios_range() to spare extra sanitize */ +static void __init e820_add_kernel_range(void) +{ + u64 start = __pa_symbol(_text); + u64 size = __pa_symbol(_end) - start; + + /* + * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and + * attempt to fix it by adding the range. We may have a confused BIOS, + * or the user may have used memmap=exactmap or memmap=xxM$yyM to + * exclude kernel range. If we really are running on top non-RAM, + * we will crash later anyways. + */ + if (e820__mapped_all(start, start + size, E820_TYPE_RAM)) + return; + + pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n"); + e820__range_remove(start, size, E820_TYPE_RAM, 0); + e820__range_add(start, size, E820_TYPE_RAM); +} + +static void __init early_reserve_memory(void) +{ + /* + * Reserve the memory occupied by the kernel between _text and + * __end_of_kernel_reserve symbols. Any kernel sections after the + * __end_of_kernel_reserve symbol must be explicitly reserved with a + * separate memblock_reserve() or they will be discarded. + */ + memblock_reserve(__pa_symbol(_text), + (unsigned long)__end_of_kernel_reserve - (unsigned long)_text); + + /* + * The first 4Kb of memory is a BIOS owned area, but generally it is + * not listed as such in the E820 table. + * + * Reserve the first 64K of memory since some BIOSes are known to + * corrupt low memory. After the real mode trampoline is allocated the + * rest of the memory below 640k is reserved. + * + * In addition, make sure page 0 is always reserved because on + * systems with L1TF its contents can be leaked to user processes. + */ + memblock_reserve(0, SZ_64K); + + early_reserve_initrd(); + + memblock_x86_reserve_range_setup_data(); + + reserve_bios_regions(); + trim_snb_memory(); +} + +/* + * Dump out kernel offset information on panic. + */ +static int +dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p) +{ + if (kaslr_enabled()) { + pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n", + kaslr_offset(), + __START_KERNEL, + __START_KERNEL_map, + MODULES_VADDR-1); + } else { + pr_emerg("Kernel Offset: disabled\n"); + } + + return 0; +} + +void x86_configure_nx(void) +{ + if (boot_cpu_has(X86_FEATURE_NX)) + __supported_pte_mask |= _PAGE_NX; + else + __supported_pte_mask &= ~_PAGE_NX; +} + +static void __init x86_report_nx(void) +{ + if (!boot_cpu_has(X86_FEATURE_NX)) { + printk(KERN_NOTICE "Notice: NX (Execute Disable) protection " + "missing in CPU!\n"); + } else { +#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) + printk(KERN_INFO "NX (Execute Disable) protection: active\n"); +#else + /* 32bit non-PAE kernel, NX cannot be used */ + printk(KERN_NOTICE "Notice: NX (Execute Disable) protection " + "cannot be enabled: non-PAE kernel!\n"); +#endif + } +} + +/* + * Determine if we were loaded by an EFI loader. If so, then we have also been + * passed the efi memmap, systab, etc., so we should use these data structures + * for initialization. Note, the efi init code path is determined by the + * global efi_enabled. This allows the same kernel image to be used on existing + * systems (with a traditional BIOS) as well as on EFI systems. + */ +/* + * setup_arch - architecture-specific boot-time initializations + * + * Note: On x86_64, fixmaps are ready for use even before this is called. + */ + +void __init setup_arch(char **cmdline_p) +{ +#ifdef CONFIG_X86_32 + memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data)); + + /* + * copy kernel address range established so far and switch + * to the proper swapper page table + */ + clone_pgd_range(swapper_pg_dir + KERNEL_PGD_BOUNDARY, + initial_page_table + KERNEL_PGD_BOUNDARY, + KERNEL_PGD_PTRS); + + load_cr3(swapper_pg_dir); + /* + * Note: Quark X1000 CPUs advertise PGE incorrectly and require + * a cr3 based tlb flush, so the following __flush_tlb_all() + * will not flush anything because the CPU quirk which clears + * X86_FEATURE_PGE has not been invoked yet. Though due to the + * load_cr3() above the TLB has been flushed already. The + * quirk is invoked before subsequent calls to __flush_tlb_all() + * so proper operation is guaranteed. + */ + __flush_tlb_all(); +#else + printk(KERN_INFO "Command line: %s\n", boot_command_line); + boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS; +#endif + + /* + * If we have OLPC OFW, we might end up relocating the fixmap due to + * reserve_top(), so do this before touching the ioremap area. + */ + olpc_ofw_detect(); + + idt_setup_early_traps(); + early_cpu_init(); + jump_label_init(); + static_call_init(); + early_ioremap_init(); + + setup_olpc_ofw_pgd(); + + ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev); + screen_info = boot_params.screen_info; + edid_info = boot_params.edid_info; +#ifdef CONFIG_X86_32 + apm_info.bios = boot_params.apm_bios_info; + ist_info = boot_params.ist_info; +#endif + saved_video_mode = boot_params.hdr.vid_mode; + bootloader_type = boot_params.hdr.type_of_loader; + if ((bootloader_type >> 4) == 0xe) { + bootloader_type &= 0xf; + bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4; + } + bootloader_version = bootloader_type & 0xf; + bootloader_version |= boot_params.hdr.ext_loader_ver << 4; + +#ifdef CONFIG_BLK_DEV_RAM + rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK; +#endif +#ifdef CONFIG_EFI + if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, + EFI32_LOADER_SIGNATURE, 4)) { + set_bit(EFI_BOOT, &efi.flags); + } else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, + EFI64_LOADER_SIGNATURE, 4)) { + set_bit(EFI_BOOT, &efi.flags); + set_bit(EFI_64BIT, &efi.flags); + } +#endif + + x86_init.oem.arch_setup(); + + /* + * Do some memory reservations *before* memory is added to memblock, so + * memblock allocations won't overwrite it. + * + * After this point, everything still needed from the boot loader or + * firmware or kernel text should be early reserved or marked not RAM in + * e820. All other memory is free game. + * + * This call needs to happen before e820__memory_setup() which calls the + * xen_memory_setup() on Xen dom0 which relies on the fact that those + * early reservations have happened already. + */ + early_reserve_memory(); + + iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1; + e820__memory_setup(); + parse_setup_data(); + + copy_edd(); + + if (!boot_params.hdr.root_flags) + root_mountflags &= ~MS_RDONLY; + setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end); + + code_resource.start = __pa_symbol(_text); + code_resource.end = __pa_symbol(_etext)-1; + rodata_resource.start = __pa_symbol(__start_rodata); + rodata_resource.end = __pa_symbol(__end_rodata)-1; + data_resource.start = __pa_symbol(_sdata); + data_resource.end = __pa_symbol(_edata)-1; + bss_resource.start = __pa_symbol(__bss_start); + bss_resource.end = __pa_symbol(__bss_stop)-1; + +#ifdef CONFIG_CMDLINE_BOOL +#ifdef CONFIG_CMDLINE_OVERRIDE + strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); +#else + if (builtin_cmdline[0]) { + /* append boot loader cmdline to builtin */ + strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE); + strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE); + strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); + } +#endif +#endif + + strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE); + *cmdline_p = command_line; + + /* + * x86_configure_nx() is called before parse_early_param() to detect + * whether hardware doesn't support NX (so that the early EHCI debug + * console setup can safely call set_fixmap()). + */ + x86_configure_nx(); + + parse_early_param(); + + if (efi_enabled(EFI_BOOT)) + efi_memblock_x86_reserve_range(); + +#ifdef CONFIG_MEMORY_HOTPLUG + /* + * Memory used by the kernel cannot be hot-removed because Linux + * cannot migrate the kernel pages. When memory hotplug is + * enabled, we should prevent memblock from allocating memory + * for the kernel. + * + * ACPI SRAT records all hotpluggable memory ranges. But before + * SRAT is parsed, we don't know about it. + * + * The kernel image is loaded into memory at very early time. We + * cannot prevent this anyway. So on NUMA system, we set any + * node the kernel resides in as un-hotpluggable. + * + * Since on modern servers, one node could have double-digit + * gigabytes memory, we can assume the memory around the kernel + * image is also un-hotpluggable. So before SRAT is parsed, just + * allocate memory near the kernel image to try the best to keep + * the kernel away from hotpluggable memory. + */ + if (movable_node_is_enabled()) + memblock_set_bottom_up(true); +#endif + + x86_report_nx(); + + apic_setup_apic_calls(); + + if (acpi_mps_check()) { +#ifdef CONFIG_X86_LOCAL_APIC + apic_is_disabled = true; +#endif + setup_clear_cpu_cap(X86_FEATURE_APIC); + } + + e820__reserve_setup_data(); + e820__finish_early_params(); + + if (efi_enabled(EFI_BOOT)) + efi_init(); + + reserve_ibft_region(); + dmi_setup(); + + /* + * VMware detection requires dmi to be available, so this + * needs to be done after dmi_setup(), for the boot CPU. + * For some guest types (Xen PV, SEV-SNP, TDX) it is required to be + * called before cache_bp_init() for setting up MTRR state. + */ + init_hypervisor_platform(); + + tsc_early_init(); + x86_init.resources.probe_roms(); + + /* after parse_early_param, so could debug it */ + insert_resource(&iomem_resource, &code_resource); + insert_resource(&iomem_resource, &rodata_resource); + insert_resource(&iomem_resource, &data_resource); + insert_resource(&iomem_resource, &bss_resource); + + e820_add_kernel_range(); + trim_bios_range(); +#ifdef CONFIG_X86_32 + if (ppro_with_ram_bug()) { + e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM, + E820_TYPE_RESERVED); + e820__update_table(e820_table); + printk(KERN_INFO "fixed physical RAM map:\n"); + e820__print_table("bad_ppro"); + } +#else + early_gart_iommu_check(); +#endif + + /* + * partially used pages are not usable - thus + * we are rounding upwards: + */ + max_pfn = e820__end_of_ram_pfn(); + + /* update e820 for memory not covered by WB MTRRs */ + cache_bp_init(); + if (mtrr_trim_uncached_memory(max_pfn)) + max_pfn = e820__end_of_ram_pfn(); + + max_possible_pfn = max_pfn; + + /* + * Define random base addresses for memory sections after max_pfn is + * defined and before each memory section base is used. + */ + kernel_randomize_memory(); + +#ifdef CONFIG_X86_32 + /* max_low_pfn get updated here */ + find_low_pfn_range(); +#else + check_x2apic(); + + /* How many end-of-memory variables you have, grandma! */ + /* need this before calling reserve_initrd */ + if (max_pfn > (1UL<<(32 - PAGE_SHIFT))) + max_low_pfn = e820__end_of_low_ram_pfn(); + else + max_low_pfn = max_pfn; + + high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1; +#endif + + /* + * Find and reserve possible boot-time SMP configuration: + */ + find_smp_config(); + + early_alloc_pgt_buf(); + + /* + * Need to conclude brk, before e820__memblock_setup() + * it could use memblock_find_in_range, could overlap with + * brk area. + */ + reserve_brk(); + + cleanup_highmap(); + + memblock_set_current_limit(ISA_END_ADDRESS); + e820__memblock_setup(); + + /* + * Needs to run after memblock setup because it needs the physical + * memory size. + */ + sev_setup_arch(); + + efi_fake_memmap(); + efi_find_mirror(); + efi_esrt_init(); + efi_mokvar_table_init(); + + /* + * The EFI specification says that boot service code won't be + * called after ExitBootServices(). This is, in fact, a lie. + */ + efi_reserve_boot_services(); + + /* preallocate 4k for mptable mpc */ + e820__memblock_alloc_reserved_mpc_new(); + +#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION + setup_bios_corruption_check(); +#endif + +#ifdef CONFIG_X86_32 + printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n", + (max_pfn_mapped<<PAGE_SHIFT) - 1); +#endif + + /* + * Find free memory for the real mode trampoline and place it there. If + * there is not enough free memory under 1M, on EFI-enabled systems + * there will be additional attempt to reclaim the memory for the real + * mode trampoline at efi_free_boot_services(). + * + * Unconditionally reserve the entire first 1M of RAM because BIOSes + * are known to corrupt low memory and several hundred kilobytes are not + * worth complex detection what memory gets clobbered. Windows does the + * same thing for very similar reasons. + * + * Moreover, on machines with SandyBridge graphics or in setups that use + * crashkernel the entire 1M is reserved anyway. + */ + x86_platform.realmode_reserve(); + + init_mem_mapping(); + + idt_setup_early_pf(); + + /* + * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features) + * with the current CR4 value. This may not be necessary, but + * auditing all the early-boot CR4 manipulation would be needed to + * rule it out. + * + * Mask off features that don't work outside long mode (just + * PCIDE for now). + */ + mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE; + + memblock_set_current_limit(get_max_mapped()); + + /* + * NOTE: On x86-32, only from this point on, fixmaps are ready for use. + */ + +#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT + if (init_ohci1394_dma_early) + init_ohci1394_dma_on_all_controllers(); +#endif + /* Allocate bigger log buffer */ + setup_log_buf(1); + + if (efi_enabled(EFI_BOOT)) { + switch (boot_params.secure_boot) { + case efi_secureboot_mode_disabled: + pr_info("Secure boot disabled\n"); + break; + case efi_secureboot_mode_enabled: + pr_info("Secure boot enabled\n"); + break; + default: + pr_info("Secure boot could not be determined\n"); + break; + } + } + + reserve_initrd(); + + acpi_table_upgrade(); + /* Look for ACPI tables and reserve memory occupied by them. */ + acpi_boot_table_init(); + + vsmp_init(); + + io_delay_init(); + + early_platform_quirks(); + + early_acpi_boot_init(); + + initmem_init(); + dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT); + + if (boot_cpu_has(X86_FEATURE_GBPAGES)) + hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT); + + /* + * Reserve memory for crash kernel after SRAT is parsed so that it + * won't consume hotpluggable memory. + */ + reserve_crashkernel(); + + memblock_find_dma_reserve(); + + if (!early_xdbc_setup_hardware()) + early_xdbc_register_console(); + + x86_init.paging.pagetable_init(); + + kasan_init(); + + /* + * Sync back kernel address range. + * + * FIXME: Can the later sync in setup_cpu_entry_areas() replace + * this call? + */ + sync_initial_page_table(); + + tboot_probe(); + + map_vsyscall(); + + x86_32_probe_apic(); + + early_quirks(); + + /* + * Read APIC and some other early information from ACPI tables. + */ + acpi_boot_init(); + x86_dtb_init(); + + /* + * get boot-time SMP configuration: + */ + get_smp_config(); + + /* + * Systems w/o ACPI and mptables might not have it mapped the local + * APIC yet, but prefill_possible_map() might need to access it. + */ + init_apic_mappings(); + + prefill_possible_map(); + + init_cpu_to_node(); + init_gi_nodes(); + + io_apic_init_mappings(); + + x86_init.hyper.guest_late_init(); + + e820__reserve_resources(); + e820__register_nosave_regions(max_pfn); + + x86_init.resources.reserve_resources(); + + e820__setup_pci_gap(); + +#ifdef CONFIG_VT +#if defined(CONFIG_VGA_CONSOLE) + if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY)) + conswitchp = &vga_con; +#endif +#endif + x86_init.oem.banner(); + + x86_init.timers.wallclock_init(); + + /* + * This needs to run before setup_local_APIC() which soft-disables the + * local APIC temporarily and that masks the thermal LVT interrupt, + * leading to softlockups on machines which have configured SMI + * interrupt delivery. + */ + therm_lvt_init(); + + mcheck_init(); + + register_refined_jiffies(CLOCK_TICK_RATE); + +#ifdef CONFIG_EFI + if (efi_enabled(EFI_BOOT)) + efi_apply_memmap_quirks(); +#endif + + unwind_init(); +} + +#ifdef CONFIG_X86_32 + +static struct resource video_ram_resource = { + .name = "Video RAM area", + .start = 0xa0000, + .end = 0xbffff, + .flags = IORESOURCE_BUSY | IORESOURCE_MEM +}; + +void __init i386_reserve_resources(void) +{ + request_resource(&iomem_resource, &video_ram_resource); + reserve_standard_io_resources(); +} + +#endif /* CONFIG_X86_32 */ + +static struct notifier_block kernel_offset_notifier = { + .notifier_call = dump_kernel_offset +}; + +static int __init register_kernel_offset_dumper(void) +{ + atomic_notifier_chain_register(&panic_notifier_list, + &kernel_offset_notifier); + return 0; +} +__initcall(register_kernel_offset_dumper); |