int arch_compat_trampoline(struct kexec_info *info)
{
if ((info->kexec_flags & KEXEC_ARCH_MASK) == KEXEC_ARCH_X86_64)
{
if (!info->rhdr.e_shdr) {
fprintf(stderr,
"A trampoline is required for cross architecture support\n");
return -1;
}
elf_rel_set_symbol(&info->rhdr, "compat_x86_64_entry32",
&info->entry, sizeof(info->entry));
info->entry = (void *)elf_rel_get_addr(&info->rhdr, "compat_x86_64");
}
return 0;
}
int elf_x86_load(int argc, char **argv, const char *buf, off_t len,
struct kexec_info *info)
{
struct mem_ehdr ehdr;
char *command_line = NULL, *modified_cmdline = NULL;
const char *append = NULL;
char *tmp_cmdline = NULL;
char *error_msg = NULL;
int result;
int command_line_len;
const char *ramdisk;
unsigned long entry, max_addr;
int arg_style;
#define ARG_STYLE_ELF 0
#define ARG_STYLE_LINUX 1
#define ARG_STYLE_NONE 2
int opt;
/* See options.h -- add any more there, too. */
static const struct option options[] = {
KEXEC_ARCH_OPTIONS
{ "command-line", 1, NULL, OPT_APPEND },
{ "append", 1, NULL, OPT_APPEND },
{ "reuse-cmdline", 0, NULL, OPT_REUSE_CMDLINE },
{ "initrd", 1, NULL, OPT_RAMDISK },
{ "ramdisk", 1, NULL, OPT_RAMDISK },
{ "args-elf", 0, NULL, OPT_ARGS_ELF },
{ "args-linux", 0, NULL, OPT_ARGS_LINUX },
{ "args-none", 0, NULL, OPT_ARGS_NONE },
{ 0, 0, NULL, 0 },
};
static const char short_options[] = KEXEC_OPT_STR "";
/*
* Parse the command line arguments
*/
arg_style = ARG_STYLE_ELF;
ramdisk = 0;
result = 0;
while((opt = getopt_long(argc, argv, short_options, options, 0)) != -1) {
switch(opt) {
default:
/* Ignore core options */
if (opt < OPT_ARCH_MAX) {
break;
}
case OPT_APPEND:
append = optarg;
break;
case OPT_REUSE_CMDLINE:
tmp_cmdline = get_command_line();
break;
case OPT_RAMDISK:
ramdisk = optarg;
break;
case OPT_ARGS_ELF:
arg_style = ARG_STYLE_ELF;
break;
case OPT_ARGS_LINUX:
arg_style = ARG_STYLE_LINUX;
break;
case OPT_ARGS_NONE:
#ifdef __i386__
arg_style = ARG_STYLE_NONE;
#else
die("--args-none only works on arch i386\n");
#endif
break;
}
}
command_line = concat_cmdline(tmp_cmdline, append);
if (tmp_cmdline) {
free(tmp_cmdline);
}
command_line_len = 0;
if (command_line) {
command_line_len = strlen(command_line) +1;
} else {
command_line = strdup("\0");
command_line_len = 1;
}
/* Need to append some command line parameters internally in case of
* taking crash dumps.
*/
if (info->kexec_flags & (KEXEC_ON_CRASH|KEXEC_PRESERVE_CONTEXT)) {
modified_cmdline = xmalloc(COMMAND_LINE_SIZE);
memset((void *)modified_cmdline, 0, COMMAND_LINE_SIZE);
if (command_line) {
strncpy(modified_cmdline, command_line,
COMMAND_LINE_SIZE);
modified_cmdline[COMMAND_LINE_SIZE - 1] = '\0';
}
}
/* Load the ELF executable */
elf_exec_build_load(info, &ehdr, buf, len, 0);
entry = ehdr.e_entry;
max_addr = elf_max_addr(&ehdr);
/* Do we want arguments? */
if (arg_style != ARG_STYLE_NONE) {
/* Load the setup code */
elf_rel_build_load(info, &info->rhdr, purgatory, purgatory_size,
0, ULONG_MAX, 1, 0);
}
if (arg_style == ARG_STYLE_NONE) {
info->entry = (void *)entry;
}
else if (arg_style == ARG_STYLE_ELF) {
unsigned long note_base;
struct entry32_regs regs;
uint32_t arg1, arg2;
/* Setup the ELF boot notes */
note_base = elf_boot_notes(info, max_addr,
command_line, command_line_len);
/* Initialize the stack arguments */
arg2 = 0; /* No return address */
arg1 = note_base;
elf_rel_set_symbol(&info->rhdr, "stack_arg32_1", &arg1, sizeof(arg1));
elf_rel_set_symbol(&info->rhdr, "stack_arg32_2", &arg2, sizeof(arg2));
/* Initialize the registers */
elf_rel_get_symbol(&info->rhdr, "entry32_regs", ®s, sizeof(regs));
regs.eip = entry; /* The entry point */
regs.esp = elf_rel_get_addr(&info->rhdr, "stack_arg32_2");
elf_rel_set_symbol(&info->rhdr, "entry32_regs", ®s, sizeof(regs));
if (ramdisk) {
error_msg = "Ramdisks not supported with generic elf arguments";
goto out;
}
}
else if (arg_style == ARG_STYLE_LINUX) {
struct x86_linux_faked_param_header *hdr;
unsigned long param_base;
const char *ramdisk_buf;
off_t ramdisk_length;
struct entry32_regs regs;
int rc = 0;
/* Get the linux parameter header */
hdr = xmalloc(sizeof(*hdr));
/* Hack: With some ld versions, vmlinux program headers show
* a gap of two pages between bss segment and data segment
* but effectively kernel considers it as bss segment and
* overwrites the any data placed there. Hence bloat the
* memsz of parameter segment to 16K to avoid being placed
* in such gaps.
* This is a makeshift solution until it is fixed in kernel
*/
param_base = add_buffer(info, hdr, sizeof(*hdr), 16*1024,
16, 0, max_addr, 1);
/* Initialize the parameter header */
memset(hdr, 0, sizeof(*hdr));
init_linux_parameters(&hdr->hdr);
/* Add a ramdisk to the current image */
ramdisk_buf = NULL;
ramdisk_length = 0;
if (ramdisk) {
ramdisk_buf = slurp_file(ramdisk, &ramdisk_length);
}
/* If panic kernel is being loaded, additional segments need
* to be created. */
if (info->kexec_flags & (KEXEC_ON_CRASH|KEXEC_PRESERVE_CONTEXT)) {
rc = load_crashdump_segments(info, modified_cmdline,
max_addr, 0);
if (rc < 0) {
result = -1;
goto out;
}
/* Use new command line. */
free(command_line);
command_line = modified_cmdline;
command_line_len = strlen(modified_cmdline) + 1;
modified_cmdline = NULL;
}
/* Tell the kernel what is going on */
setup_linux_bootloader_parameters(info, &hdr->hdr, param_base,
offsetof(struct x86_linux_faked_param_header, command_line),
command_line, command_line_len,
ramdisk_buf, ramdisk_length);
/* Fill in the information bios calls would usually provide */
setup_linux_system_parameters(info, &hdr->hdr);
/* Initialize the registers */
elf_rel_get_symbol(&info->rhdr, "entry32_regs", ®s, sizeof(regs));
regs.ebx = 0; /* Bootstrap processor */
regs.esi = param_base; /* Pointer to the parameters */
regs.eip = entry; /* The entry point */
regs.esp = elf_rel_get_addr(&info->rhdr, "stack_end"); /* Stack, unused */
elf_rel_set_symbol(&info->rhdr, "entry32_regs", ®s, sizeof(regs));
}
else {
static int ppc_load_bare_bits(int argc, char **argv, const char *buf,
off_t len, struct kexec_info *info, unsigned int load_addr,
unsigned int ep)
{
char *command_line;
int command_line_len;
char *dtb;
unsigned int addr;
unsigned long dtb_addr;
#define FIXUP_ENTRYS (20)
char *fixup_nodes[FIXUP_ENTRYS + 1];
int cur_fixup = 0;
int opt;
int ret;
command_line = NULL;
dtb = NULL;
while ((opt = getopt_long(argc, argv, short_options, options, 0)) != -1) {
switch (opt) {
default:
/* Ignore core options */
if (opt < OPT_ARCH_MAX) {
break;
}
case '?':
usage();
return -1;
case OPT_APPEND:
command_line = optarg;
break;
case OPT_DTB:
dtb = optarg;
break;
case OPT_NODES:
if (cur_fixup >= FIXUP_ENTRYS) {
fprintf(stderr, "The number of entries for the fixup is too large\n");
exit(1);
}
fixup_nodes[cur_fixup] = optarg;
cur_fixup++;
break;
}
}
command_line_len = 0;
if (command_line)
command_line_len = strlen(command_line) + 1;
fixup_nodes[cur_fixup] = NULL;
/*
* len contains the length of the whole kernel image except the bss
* section. The 3 MiB should cover it. The purgatory and the dtb are
* allocated from memtop down towards zero so we should never get too
* close to the bss :)
*/
ret = valid_memory_range(info, load_addr, len + 3 * 1024 * 1024);
if (!ret) {
printf("Can't add kernel to addr 0x%08x len %ld\n",
load_addr, len + 3 * 1024 * 1024);
return -1;
}
add_segment(info, buf, len, load_addr, len + 3 * 1024 * 1024);
if (dtb) {
char *blob_buf;
off_t blob_size = 0;
/* Grab device tree from buffer */
blob_buf = slurp_file(dtb, &blob_size);
if (!blob_buf || !blob_size)
die("Device tree seems to be an empty file.\n");
blob_buf = fixup_dtb_nodes(blob_buf, &blob_size, fixup_nodes, command_line);
dtb_addr = add_buffer(info, blob_buf, blob_size, blob_size, 0, 0,
KERNEL_ACCESS_TOP, -1);
} else {
dtb_addr = 0;
}
elf_rel_build_load(info, &info->rhdr, (const char *)purgatory,
purgatory_size, 0, -1, -1, 0);
/* set various variables for the purgatory */
addr = ep;
elf_rel_set_symbol(&info->rhdr, "kernel", &addr, sizeof(addr));
addr = dtb_addr;
elf_rel_set_symbol(&info->rhdr, "dt_offset", &addr, sizeof(addr));
addr = rmo_top;
elf_rel_set_symbol(&info->rhdr, "mem_size", &addr, sizeof(addr));
#define PUL_STACK_SIZE (16 * 1024)
addr = locate_hole(info, PUL_STACK_SIZE, 0, 0, -1, 1);
addr += PUL_STACK_SIZE;
elf_rel_set_symbol(&info->rhdr, "pul_stack", &addr, sizeof(addr));
/* No allocation past here in order not to overwrite the stack */
#undef PUL_STACK_SIZE
addr = elf_rel_get_addr(&info->rhdr, "purgatory_start");
info->entry = (void *)addr;
return 0;
}
int do_bzImage_load(struct kexec_info *info,
const char *kernel, off_t kernel_len,
const char *command_line, off_t command_line_len,
const char *initrd, off_t initrd_len,
int real_mode_entry, int debug)
{
struct x86_linux_header setup_header;
struct x86_linux_param_header *real_mode;
int setup_sects;
char *kernel_version;
size_t size;
int kern16_size;
unsigned long setup_base, setup_size;
struct entry32_regs regs32;
struct entry16_regs regs16;
unsigned int relocatable_kernel = 0;
unsigned long kernel32_load_addr;
char *modified_cmdline;
/*
* Find out about the file I am about to load.
*/
if (kernel_len < sizeof(setup_header)) {
return -1;
}
memcpy(&setup_header, kernel, sizeof(setup_header));
setup_sects = setup_header.setup_sects;
if (setup_sects == 0) {
setup_sects = 4;
}
kern16_size = (setup_sects +1) *512;
kernel_version = ((unsigned char *)&setup_header) + 512 + setup_header.kver_addr;
if (kernel_len < kern16_size) {
fprintf(stderr, "BzImage truncated?\n");
return -1;
}
if (setup_header.protocol_version >= 0x0205) {
relocatable_kernel = setup_header.relocatable_kernel;
dfprintf(stdout, "bzImage is relocatable\n");
}
/* Can't use bzImage for crash dump purposes with real mode entry */
if((info->kexec_flags & KEXEC_ON_CRASH) && real_mode_entry) {
fprintf(stderr, "Can't use bzImage for crash dump purposes"
" with real mode entry\n");
return -1;
}
if((info->kexec_flags & KEXEC_ON_CRASH) && !relocatable_kernel) {
fprintf(stderr, "BzImage is not relocatable. Can't be used"
" as capture kernel.\n");
return -1;
}
/* Need to append some command line parameters internally in case of
* taking crash dumps.
*/
if (info->kexec_flags & KEXEC_ON_CRASH) {
modified_cmdline = xmalloc(COMMAND_LINE_SIZE);
memset((void *)modified_cmdline, 0, COMMAND_LINE_SIZE);
if (command_line) {
strncpy(modified_cmdline, command_line,
COMMAND_LINE_SIZE);
modified_cmdline[COMMAND_LINE_SIZE - 1] = '\0';
}
/* If panic kernel is being loaded, additional segments need
* to be created. load_crashdump_segments will take care of
* loading the segments as high in memory as possible, hence
* in turn as away as possible from kernel to avoid being
* stomped by the kernel.
*/
if (load_crashdump_segments(info, modified_cmdline, -1, 0) < 0)
return -1;
/* Use new command line buffer */
command_line = modified_cmdline;
command_line_len = strlen(command_line) +1;
}
/* Load the trampoline. This must load at a higher address
* the the argument/parameter segment or the kernel will stomp
* it's gdt.
*
* x86_64 purgatory code has got relocations type R_X86_64_32S
* that means purgatory got to be loaded within first 2G otherwise
* overflow takes place while applying relocations.
*/
if (!real_mode_entry && relocatable_kernel)
elf_rel_build_load(info, &info->rhdr, purgatory, purgatory_size,
0x3000, 0x7fffffff, -1, 0);
else
elf_rel_build_load(info, &info->rhdr, purgatory, purgatory_size,
0x3000, 640*1024, -1, 0);
dfprintf(stdout, "Loaded purgatory at addr 0x%lx\n",
info->rhdr.rel_addr);
/* The argument/parameter segment */
setup_size = kern16_size + command_line_len;
real_mode = xmalloc(setup_size);
memcpy(real_mode, kernel, kern16_size);
if (info->kexec_flags & KEXEC_ON_CRASH) {
/* If using bzImage for capture kernel, then we will not be
* executing real mode code. setup segment can be loaded
* anywhere as we will be just reading command line.
*/
setup_base = add_buffer(info, real_mode, setup_size, setup_size,
16, 0x3000, -1, 1);
}
else if (real_mode->protocol_version >= 0x0200) {
/* Careful setup_base must be greater than 8K */
setup_base = add_buffer(info, real_mode, setup_size, setup_size,
16, 0x3000, 640*1024, 1);
} else {
add_segment(info, real_mode, setup_size, SETUP_BASE, setup_size);
setup_base = SETUP_BASE;
}
dfprintf(stdout, "Loaded real-mode code and command line at 0x%lx\n",
setup_base);
/* Verify purgatory loads higher than the parameters */
if (info->rhdr.rel_addr < setup_base) {
die("Could not put setup code above the kernel parameters\n");
}
/* The main kernel segment */
size = kernel_len - kern16_size;
if (real_mode->protocol_version >=0x0205 && relocatable_kernel) {
/* Relocatable bzImage */
unsigned long kern_align = real_mode->kernel_alignment;
unsigned long kernel32_max_addr = DEFAULT_BZIMAGE_ADDR_MAX;
if (real_mode->protocol_version >= 0x0203) {
if (kernel32_max_addr > real_mode->initrd_addr_max)
kernel32_max_addr = real_mode->initrd_addr_max;
}
kernel32_load_addr = add_buffer(info, kernel + kern16_size,
size, size, kern_align,
0x100000, kernel32_max_addr,
1);
}
else {
kernel32_load_addr = KERN32_BASE;
add_segment(info, kernel + kern16_size, size,
kernel32_load_addr, size);
}
dfprintf(stdout, "Loaded 32bit kernel at 0x%lx\n", kernel32_load_addr);
/* Tell the kernel what is going on */
setup_linux_bootloader_parameters(info, real_mode, setup_base,
kern16_size, command_line, command_line_len,
initrd, initrd_len);
/* Get the initial register values */
elf_rel_get_symbol(&info->rhdr, "entry16_regs", ®s16, sizeof(regs16));
elf_rel_get_symbol(&info->rhdr, "entry32_regs", ®s32, sizeof(regs32));
/*
* Initialize the 32bit start information.
*/
regs32.eax = 0; /* unused */
regs32.ebx = 0; /* 0 == boot not AP processor start */
regs32.ecx = 0; /* unused */
regs32.edx = 0; /* unused */
regs32.esi = setup_base; /* kernel parameters */
regs32.edi = 0; /* unused */
regs32.esp = elf_rel_get_addr(&info->rhdr, "stack_end"); /* stack, unused */
regs32.ebp = 0; /* unused */
regs32.eip = kernel32_load_addr; /* kernel entry point */
/*
* Initialize the 16bit start information.
*/
regs16.cs = (setup_base>>4) + 0x20;
regs16.ip = 0;
regs16.ss = (elf_rel_get_addr(&info->rhdr, "stack_end") - 64*1024) >> 4;
regs16.esp = 0xFFFC;
if (real_mode_entry) {
printf("Starting the kernel in real mode\n");
regs32.eip = elf_rel_get_addr(&info->rhdr, "entry16");
}
if (real_mode_entry && debug) {
unsigned long entry16_debug, pre32, first32;
uint32_t old_first32;
/* Find the location of the symbols */
entry16_debug = elf_rel_get_addr(&info->rhdr, "entry16_debug");
pre32 = elf_rel_get_addr(&info->rhdr, "entry16_debug_pre32");
first32 = elf_rel_get_addr(&info->rhdr, "entry16_debug_first32");
/* Hook all of the linux kernel hooks */
real_mode->rmode_switch_cs = entry16_debug >> 4;
real_mode->rmode_switch_ip = pre32 - entry16_debug;
old_first32 = real_mode->kernel_start;
real_mode->kernel_start = first32;
elf_rel_set_symbol(&info->rhdr, "entry16_debug_old_first32",
&old_first32, sizeof(old_first32));
regs32.eip = entry16_debug;
}