Contributors: 36
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Vivek Goyal |
514 |
17.85% |
5 |
6.85% |
| Huang Ying |
458 |
15.90% |
5 |
6.85% |
| David Woodhouse |
391 |
13.58% |
12 |
16.44% |
| Kairui Song |
339 |
11.77% |
2 |
2.74% |
| Eric W. Biedermann |
193 |
6.70% |
2 |
2.74% |
| Yinghai Lu |
192 |
6.67% |
4 |
5.48% |
| Xunlei Pang |
187 |
6.49% |
3 |
4.11% |
| Tao Liu |
120 |
4.17% |
1 |
1.37% |
| Coiby Xu |
112 |
3.89% |
1 |
1.37% |
| Philipp Rudo |
88 |
3.06% |
2 |
2.74% |
| Tom Lendacky |
85 |
2.95% |
5 |
6.85% |
| Lianbo Jiang |
40 |
1.39% |
2 |
2.74% |
| Tetsuo Handa |
32 |
1.11% |
1 |
1.37% |
| Kirill A. Shutemov |
30 |
1.04% |
1 |
1.37% |
| Baoquan He |
22 |
0.76% |
4 |
5.48% |
| David Kaplan |
11 |
0.38% |
1 |
1.37% |
| Magnus Damm |
9 |
0.31% |
1 |
1.37% |
| Yuntao Wang |
8 |
0.28% |
2 |
2.74% |
| K.Prasad |
6 |
0.21% |
1 |
1.37% |
| AKASHI Takahiro |
5 |
0.17% |
1 |
1.37% |
| Ingo Molnar |
5 |
0.17% |
1 |
1.37% |
| Jiang Liu |
4 |
0.14% |
2 |
2.74% |
| Peter Zijlstra |
3 |
0.10% |
1 |
1.37% |
| Andi Kleen |
3 |
0.10% |
1 |
1.37% |
| Jiri Kosina |
3 |
0.10% |
1 |
1.37% |
| Avi Kivity |
3 |
0.10% |
1 |
1.37% |
| Laura Abbott |
3 |
0.10% |
1 |
1.37% |
| H. J. Lu |
3 |
0.10% |
1 |
1.37% |
| Thomas Gleixner |
2 |
0.07% |
1 |
1.37% |
| Gary Hade |
2 |
0.07% |
1 |
1.37% |
| Erich Focht |
2 |
0.07% |
1 |
1.37% |
| Jaswinder Singh Rajput |
1 |
0.03% |
1 |
1.37% |
| Linus Torvalds |
1 |
0.03% |
1 |
1.37% |
| Michael Matz |
1 |
0.03% |
1 |
1.37% |
| Jan Beulich |
1 |
0.03% |
1 |
1.37% |
| Andrew Morton |
1 |
0.03% |
1 |
1.37% |
| Total |
2880 |
|
73 |
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* handle transition of Linux booting another kernel
* Copyright (C) 2002-2005 Eric Biederman <ebiederm@xmission.com>
*/
#define pr_fmt(fmt) "kexec: " fmt
#include <linux/mm.h>
#include <linux/kexec.h>
#include <linux/string.h>
#include <linux/gfp.h>
#include <linux/reboot.h>
#include <linux/numa.h>
#include <linux/ftrace.h>
#include <linux/io.h>
#include <linux/suspend.h>
#include <linux/vmalloc.h>
#include <linux/efi.h>
#include <linux/cc_platform.h>
#include <asm/init.h>
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
#include <asm/io_apic.h>
#include <asm/debugreg.h>
#include <asm/kexec-bzimage64.h>
#include <asm/setup.h>
#include <asm/set_memory.h>
#include <asm/cpu.h>
#include <asm/efi.h>
#ifdef CONFIG_ACPI
/*
* Used while adding mapping for ACPI tables.
* Can be reused when other iomem regions need be mapped
*/
struct init_pgtable_data {
struct x86_mapping_info *info;
pgd_t *level4p;
};
static int mem_region_callback(struct resource *res, void *arg)
{
struct init_pgtable_data *data = arg;
return kernel_ident_mapping_init(data->info, data->level4p,
res->start, res->end + 1);
}
static int
map_acpi_tables(struct x86_mapping_info *info, pgd_t *level4p)
{
struct init_pgtable_data data;
unsigned long flags;
int ret;
data.info = info;
data.level4p = level4p;
flags = IORESOURCE_MEM | IORESOURCE_BUSY;
ret = walk_iomem_res_desc(IORES_DESC_ACPI_TABLES, flags, 0, -1,
&data, mem_region_callback);
if (ret && ret != -EINVAL)
return ret;
/* ACPI tables could be located in ACPI Non-volatile Storage region */
ret = walk_iomem_res_desc(IORES_DESC_ACPI_NV_STORAGE, flags, 0, -1,
&data, mem_region_callback);
if (ret && ret != -EINVAL)
return ret;
return 0;
}
#else
static int map_acpi_tables(struct x86_mapping_info *info, pgd_t *level4p) { return 0; }
#endif
static int map_mmio_serial(struct x86_mapping_info *info, pgd_t *level4p)
{
unsigned long mstart, mend;
if (!kexec_debug_8250_mmio32)
return 0;
mstart = kexec_debug_8250_mmio32 & PAGE_MASK;
mend = (kexec_debug_8250_mmio32 + PAGE_SIZE + 23) & PAGE_MASK;
pr_info("Map PCI serial at %lx - %lx\n", mstart, mend);
return kernel_ident_mapping_init(info, level4p, mstart, mend);
}
#ifdef CONFIG_KEXEC_FILE
const struct kexec_file_ops * const kexec_file_loaders[] = {
&kexec_bzImage64_ops,
NULL
};
#endif
static int
map_efi_systab(struct x86_mapping_info *info, pgd_t *level4p)
{
#ifdef CONFIG_EFI
unsigned long mstart, mend;
void *kaddr;
int ret;
if (!efi_enabled(EFI_BOOT))
return 0;
mstart = (boot_params.efi_info.efi_systab |
((u64)boot_params.efi_info.efi_systab_hi<<32));
if (efi_enabled(EFI_64BIT))
mend = mstart + sizeof(efi_system_table_64_t);
else
mend = mstart + sizeof(efi_system_table_32_t);
if (!mstart)
return 0;
ret = kernel_ident_mapping_init(info, level4p, mstart, mend);
if (ret)
return ret;
kaddr = memremap(mstart, mend - mstart, MEMREMAP_WB);
if (!kaddr) {
pr_err("Could not map UEFI system table\n");
return -ENOMEM;
}
mstart = efi_config_table;
if (efi_enabled(EFI_64BIT)) {
efi_system_table_64_t *stbl = (efi_system_table_64_t *)kaddr;
mend = mstart + sizeof(efi_config_table_64_t) * stbl->nr_tables;
} else {
efi_system_table_32_t *stbl = (efi_system_table_32_t *)kaddr;
mend = mstart + sizeof(efi_config_table_32_t) * stbl->nr_tables;
}
memunmap(kaddr);
return kernel_ident_mapping_init(info, level4p, mstart, mend);
#endif
return 0;
}
static void free_transition_pgtable(struct kimage *image)
{
free_page((unsigned long)image->arch.p4d);
image->arch.p4d = NULL;
free_page((unsigned long)image->arch.pud);
image->arch.pud = NULL;
free_page((unsigned long)image->arch.pmd);
image->arch.pmd = NULL;
free_page((unsigned long)image->arch.pte);
image->arch.pte = NULL;
}
static int init_transition_pgtable(struct kimage *image, pgd_t *pgd,
unsigned long control_page)
{
pgprot_t prot = PAGE_KERNEL_EXEC_NOENC;
unsigned long vaddr, paddr;
int result = -ENOMEM;
p4d_t *p4d;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
/*
* For the transition to the identity mapped page tables, the control
* code page also needs to be mapped at the virtual address it starts
* off running from.
*/
vaddr = (unsigned long)__va(control_page);
paddr = control_page;
pgd += pgd_index(vaddr);
if (!pgd_present(*pgd)) {
p4d = (p4d_t *)get_zeroed_page(GFP_KERNEL);
if (!p4d)
goto err;
image->arch.p4d = p4d;
set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE));
}
p4d = p4d_offset(pgd, vaddr);
if (!p4d_present(*p4d)) {
pud = (pud_t *)get_zeroed_page(GFP_KERNEL);
if (!pud)
goto err;
image->arch.pud = pud;
set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE));
}
pud = pud_offset(p4d, vaddr);
if (!pud_present(*pud)) {
pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL);
if (!pmd)
goto err;
image->arch.pmd = pmd;
set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
}
pmd = pmd_offset(pud, vaddr);
if (!pmd_present(*pmd)) {
pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
if (!pte)
goto err;
image->arch.pte = pte;
set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
}
pte = pte_offset_kernel(pmd, vaddr);
if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
prot = PAGE_KERNEL_EXEC;
set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, prot));
return 0;
err:
return result;
}
static void *alloc_pgt_page(void *data)
{
struct kimage *image = (struct kimage *)data;
struct page *page;
void *p = NULL;
page = kimage_alloc_control_pages(image, 0);
if (page) {
p = page_address(page);
clear_page(p);
}
return p;
}
static int init_pgtable(struct kimage *image, unsigned long control_page)
{
struct x86_mapping_info info = {
.alloc_pgt_page = alloc_pgt_page,
.context = image,
.page_flag = __PAGE_KERNEL_LARGE_EXEC,
.kernpg_flag = _KERNPG_TABLE_NOENC,
};
unsigned long mstart, mend;
int result;
int i;
image->arch.pgd = alloc_pgt_page(image);
if (!image->arch.pgd)
return -ENOMEM;
if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
info.page_flag |= _PAGE_ENC;
info.kernpg_flag |= _PAGE_ENC;
}
if (direct_gbpages)
info.direct_gbpages = true;
for (i = 0; i < nr_pfn_mapped; i++) {
mstart = pfn_mapped[i].start << PAGE_SHIFT;
mend = pfn_mapped[i].end << PAGE_SHIFT;
result = kernel_ident_mapping_init(&info, image->arch.pgd,
mstart, mend);
if (result)
return result;
}
/*
* segments's mem ranges could be outside 0 ~ max_pfn,
* for example when jump back to original kernel from kexeced kernel.
* or first kernel is booted with user mem map, and second kernel
* could be loaded out of that range.
*/
for (i = 0; i < image->nr_segments; i++) {
mstart = image->segment[i].mem;
mend = mstart + image->segment[i].memsz;
result = kernel_ident_mapping_init(&info, image->arch.pgd,
mstart, mend);
if (result)
return result;
}
/*
* Prepare EFI systab and ACPI tables for kexec kernel since they are
* not covered by pfn_mapped.
*/
result = map_efi_systab(&info, image->arch.pgd);
if (result)
return result;
result = map_acpi_tables(&info, image->arch.pgd);
if (result)
return result;
result = map_mmio_serial(&info, image->arch.pgd);
if (result)
return result;
/*
* This must be last because the intermediate page table pages it
* allocates will not be control pages and may overlap the image.
*/
return init_transition_pgtable(image, image->arch.pgd, control_page);
}
static void load_segments(void)
{
__asm__ __volatile__ (
"\tmovl %0,%%ds\n"
"\tmovl %0,%%es\n"
"\tmovl %0,%%ss\n"
"\tmovl %0,%%fs\n"
"\tmovl %0,%%gs\n"
: : "a" (__KERNEL_DS) : "memory"
);
}
static void prepare_debug_idt(unsigned long control_page, unsigned long vec_ofs)
{
gate_desc idtentry = { 0 };
int i;
idtentry.bits.p = 1;
idtentry.bits.type = GATE_TRAP;
idtentry.segment = __KERNEL_CS;
idtentry.offset_low = (control_page & 0xFFFF) + vec_ofs;
idtentry.offset_middle = (control_page >> 16) & 0xFFFF;
idtentry.offset_high = control_page >> 32;
for (i = 0; i < 16; i++) {
kexec_debug_idt[i] = idtentry;
idtentry.offset_low += KEXEC_DEBUG_EXC_HANDLER_SIZE;
}
}
int machine_kexec_prepare(struct kimage *image)
{
void *control_page = page_address(image->control_code_page);
unsigned long reloc_start = (unsigned long)__relocate_kernel_start;
unsigned long reloc_end = (unsigned long)__relocate_kernel_end;
int result;
/* Setup the identity mapped 64bit page table */
result = init_pgtable(image, __pa(control_page));
if (result)
return result;
kexec_va_control_page = (unsigned long)control_page;
kexec_pa_table_page = (unsigned long)__pa(image->arch.pgd);
if (image->type == KEXEC_TYPE_DEFAULT)
kexec_pa_swap_page = page_to_pfn(image->swap_page) << PAGE_SHIFT;
prepare_debug_idt((unsigned long)__pa(control_page),
(unsigned long)kexec_debug_exc_vectors - reloc_start);
__memcpy(control_page, __relocate_kernel_start, reloc_end - reloc_start);
set_memory_rox((unsigned long)control_page, 1);
return 0;
}
void machine_kexec_cleanup(struct kimage *image)
{
void *control_page = page_address(image->control_code_page);
set_memory_nx((unsigned long)control_page, 1);
set_memory_rw((unsigned long)control_page, 1);
free_transition_pgtable(image);
}
/*
* Do not allocate memory (or fail in any way) in machine_kexec().
* We are past the point of no return, committed to rebooting now.
*/
void __nocfi machine_kexec(struct kimage *image)
{
unsigned long reloc_start = (unsigned long)__relocate_kernel_start;
relocate_kernel_fn *relocate_kernel_ptr;
unsigned int host_mem_enc_active;
int save_ftrace_enabled;
void *control_page;
/*
* This must be done before load_segments() since if call depth tracking
* is used then GS must be valid to make any function calls.
*/
host_mem_enc_active = cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT);
#ifdef CONFIG_KEXEC_JUMP
if (image->preserve_context)
save_processor_state();
#endif
save_ftrace_enabled = __ftrace_enabled_save();
/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
hw_breakpoint_disable();
cet_disable();
if (image->preserve_context) {
#ifdef CONFIG_X86_IO_APIC
/*
* We need to put APICs in legacy mode so that we can
* get timer interrupts in second kernel. kexec/kdump
* paths already have calls to restore_boot_irq_mode()
* in one form or other. kexec jump path also need one.
*/
clear_IO_APIC();
restore_boot_irq_mode();
#endif
}
control_page = page_address(image->control_code_page);
/*
* Allow for the possibility that relocate_kernel might not be at
* the very start of the page.
*/
relocate_kernel_ptr = control_page + (unsigned long)relocate_kernel - reloc_start;
/*
* The segment registers are funny things, they have both a
* visible and an invisible part. Whenever the visible part is
* set to a specific selector, the invisible part is loaded
* with from a table in memory. At no other time is the
* descriptor table in memory accessed.
*
* Take advantage of this here by force loading the segments,
* before the GDT is zapped with an invalid value.
*/
load_segments();
/* now call it */
image->start = relocate_kernel_ptr((unsigned long)image->head,
virt_to_phys(control_page),
image->start,
image->preserve_context,
host_mem_enc_active);
#ifdef CONFIG_KEXEC_JUMP
if (image->preserve_context)
restore_processor_state();
#endif
__ftrace_enabled_restore(save_ftrace_enabled);
}
/* arch-dependent functionality related to kexec file-based syscall */
#ifdef CONFIG_KEXEC_FILE
/*
* Apply purgatory relocations.
*
* @pi: Purgatory to be relocated.
* @section: Section relocations applying to.
* @relsec: Section containing RELAs.
* @symtabsec: Corresponding symtab.
*
* TODO: Some of the code belongs to generic code. Move that in kexec.c.
*/
int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
Elf_Shdr *section, const Elf_Shdr *relsec,
const Elf_Shdr *symtabsec)
{
unsigned int i;
Elf64_Rela *rel;
Elf64_Sym *sym;
void *location;
unsigned long address, sec_base, value;
const char *strtab, *name, *shstrtab;
const Elf_Shdr *sechdrs;
/* String & section header string table */
sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
strtab = (char *)pi->ehdr + sechdrs[symtabsec->sh_link].sh_offset;
shstrtab = (char *)pi->ehdr + sechdrs[pi->ehdr->e_shstrndx].sh_offset;
rel = (void *)pi->ehdr + relsec->sh_offset;
pr_debug("Applying relocate section %s to %u\n",
shstrtab + relsec->sh_name, relsec->sh_info);
for (i = 0; i < relsec->sh_size / sizeof(*rel); i++) {
/*
* rel[i].r_offset contains byte offset from beginning
* of section to the storage unit affected.
*
* This is location to update. This is temporary buffer
* where section is currently loaded. This will finally be
* loaded to a different address later, pointed to by
* ->sh_addr. kexec takes care of moving it
* (kexec_load_segment()).
*/
location = pi->purgatory_buf;
location += section->sh_offset;
location += rel[i].r_offset;
/* Final address of the location */
address = section->sh_addr + rel[i].r_offset;
/*
* rel[i].r_info contains information about symbol table index
* w.r.t which relocation must be made and type of relocation
* to apply. ELF64_R_SYM() and ELF64_R_TYPE() macros get
* these respectively.
*/
sym = (void *)pi->ehdr + symtabsec->sh_offset;
sym += ELF64_R_SYM(rel[i].r_info);
if (sym->st_name)
name = strtab + sym->st_name;
else
name = shstrtab + sechdrs[sym->st_shndx].sh_name;
pr_debug("Symbol: %s info: %02x shndx: %02x value=%llx size: %llx\n",
name, sym->st_info, sym->st_shndx, sym->st_value,
sym->st_size);
if (sym->st_shndx == SHN_UNDEF) {
pr_err("Undefined symbol: %s\n", name);
return -ENOEXEC;
}
if (sym->st_shndx == SHN_COMMON) {
pr_err("symbol '%s' in common section\n", name);
return -ENOEXEC;
}
if (sym->st_shndx == SHN_ABS)
sec_base = 0;
else if (sym->st_shndx >= pi->ehdr->e_shnum) {
pr_err("Invalid section %d for symbol %s\n",
sym->st_shndx, name);
return -ENOEXEC;
} else
sec_base = pi->sechdrs[sym->st_shndx].sh_addr;
value = sym->st_value;
value += sec_base;
value += rel[i].r_addend;
switch (ELF64_R_TYPE(rel[i].r_info)) {
case R_X86_64_NONE:
break;
case R_X86_64_64:
*(u64 *)location = value;
break;
case R_X86_64_32:
*(u32 *)location = value;
if (value != *(u32 *)location)
goto overflow;
break;
case R_X86_64_32S:
*(s32 *)location = value;
if ((s64)value != *(s32 *)location)
goto overflow;
break;
case R_X86_64_PC32:
case R_X86_64_PLT32:
value -= (u64)address;
*(u32 *)location = value;
break;
default:
pr_err("Unknown rela relocation: %llu\n",
ELF64_R_TYPE(rel[i].r_info));
return -ENOEXEC;
}
}
return 0;
overflow:
pr_err("Overflow in relocation type %d value 0x%lx\n",
(int)ELF64_R_TYPE(rel[i].r_info), value);
return -ENOEXEC;
}
int arch_kimage_file_post_load_cleanup(struct kimage *image)
{
vfree(image->elf_headers);
image->elf_headers = NULL;
image->elf_headers_sz = 0;
return kexec_image_post_load_cleanup_default(image);
}
#endif /* CONFIG_KEXEC_FILE */
#ifdef CONFIG_CRASH_DUMP
static int
kexec_mark_range(unsigned long start, unsigned long end, bool protect)
{
struct page *page;
unsigned int nr_pages;
/*
* For physical range: [start, end]. We must skip the unassigned
* crashk resource with zero-valued "end" member.
*/
if (!end || start > end)
return 0;
page = pfn_to_page(start >> PAGE_SHIFT);
nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1;
if (protect)
return set_pages_ro(page, nr_pages);
else
return set_pages_rw(page, nr_pages);
}
static void kexec_mark_crashkres(bool protect)
{
unsigned long control;
kexec_mark_range(crashk_low_res.start, crashk_low_res.end, protect);
/* Don't touch the control code page used in crash_kexec().*/
control = PFN_PHYS(page_to_pfn(kexec_crash_image->control_code_page));
kexec_mark_range(crashk_res.start, control - 1, protect);
control += KEXEC_CONTROL_PAGE_SIZE;
kexec_mark_range(control, crashk_res.end, protect);
}
/* make the memory storing dm crypt keys in/accessible */
static void kexec_mark_dm_crypt_keys(bool protect)
{
unsigned long start_paddr, end_paddr;
unsigned int nr_pages;
if (kexec_crash_image->dm_crypt_keys_addr) {
start_paddr = kexec_crash_image->dm_crypt_keys_addr;
end_paddr = start_paddr + kexec_crash_image->dm_crypt_keys_sz - 1;
nr_pages = (PAGE_ALIGN(end_paddr) - PAGE_ALIGN_DOWN(start_paddr))/PAGE_SIZE;
if (protect)
set_memory_np((unsigned long)phys_to_virt(start_paddr), nr_pages);
else
__set_memory_prot(
(unsigned long)phys_to_virt(start_paddr),
nr_pages,
__pgprot(_PAGE_PRESENT | _PAGE_NX | _PAGE_RW));
}
}
void arch_kexec_protect_crashkres(void)
{
kexec_mark_crashkres(true);
kexec_mark_dm_crypt_keys(true);
}
void arch_kexec_unprotect_crashkres(void)
{
kexec_mark_dm_crypt_keys(false);
kexec_mark_crashkres(false);
}
#endif
/*
* During a traditional boot under SME, SME will encrypt the kernel,
* so the SME kexec kernel also needs to be un-encrypted in order to
* replicate a normal SME boot.
*
* During a traditional boot under SEV, the kernel has already been
* loaded encrypted, so the SEV kexec kernel needs to be encrypted in
* order to replicate a normal SEV boot.
*/
int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp)
{
if (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))
return 0;
/*
* If host memory encryption is active we need to be sure that kexec
* pages are not encrypted because when we boot to the new kernel the
* pages won't be accessed encrypted (initially).
*/
return set_memory_decrypted((unsigned long)vaddr, pages);
}
void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages)
{
if (!cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT))
return;
/*
* If host memory encryption is active we need to reset the pages back
* to being an encrypted mapping before freeing them.
*/
set_memory_encrypted((unsigned long)vaddr, pages);
}