* [PATCH 1/3] [PATCH 1/3] kexec: split kexec_file syscall code to kexec_file.c
2015-07-13 2:13 [PATCH 0/3] kexec: refactor CONFIG_KEXEC/CONFIG_KEXEC_FILE Kconfig dyoung
@ 2015-07-13 2:13 ` dyoung
2015-07-13 2:13 ` [PATCH 2/3] [PATCH 2/3] kexec: split kexec_load syscall from kexec core code dyoung
` (2 subsequent siblings)
3 siblings, 0 replies; 14+ messages in thread
From: dyoung @ 2015-07-13 2:13 UTC (permalink / raw)
To: linux-kernel, kexec
Cc: dyoung, ebiederm, vgoyal, ptesarik, tytso, jwboyer, dhowells
[-- Attachment #1: 0001-kexec-split-kexec_file-syscall-code-to-kexec_file.c.patch --]
[-- Type: text/plain, Size: 59028 bytes --]
Split kexec_file syscall related code to another file kernel/kexec_file.c
so that the #ifdef CONFIG_KEXEC_FILE in kexec.c can be dropped.
Sharing variables and functions are moved to kernel/kexec_internal.h per
suggestion from Vivek and Petr.
Signed-off-by: Dave Young <dyoung@redhat.com>
---
kernel/Makefile | 1 +
kernel/kexec.c | 1055 +----------------------------------------------
kernel/kexec_file.c | 1044 ++++++++++++++++++++++++++++++++++++++++++++++
kernel/kexec_internal.h | 22 +
4 files changed, 1077 insertions(+), 1045 deletions(-)
create mode 100644 kernel/kexec_file.c
create mode 100644 kernel/kexec_internal.h
diff --git a/kernel/Makefile b/kernel/Makefile
index 43c4c92..f178fe4 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_MODULE_SIG) += module_signing.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
obj-$(CONFIG_KEXEC) += kexec.o
+obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
obj-$(CONFIG_COMPAT) += compat.o
obj-$(CONFIG_CGROUPS) += cgroup.o
diff --git a/kernel/kexec.c b/kernel/kexec.c
index a785c10..641b2db 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -31,7 +31,6 @@
#include <linux/pm.h>
#include <linux/cpu.h>
#include <linux/console.h>
-#include <linux/vmalloc.h>
#include <linux/swap.h>
#include <linux/syscore_ops.h>
#include <linux/compiler.h>
@@ -44,6 +43,9 @@
#include <crypto/hash.h>
#include <crypto/sha.h>
+#include "kexec_internal.h"
+
+DEFINE_MUTEX(kexec_mutex);
/* Per cpu memory for storing cpu states in case of system crash. */
note_buf_t __percpu *crash_notes;
@@ -57,16 +59,6 @@ size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);
/* Flag to indicate we are going to kexec a new kernel */
bool kexec_in_progress = false;
-/*
- * Declare these symbols weak so that if architecture provides a purgatory,
- * these will be overridden.
- */
-char __weak kexec_purgatory[0];
-size_t __weak kexec_purgatory_size = 0;
-
-#ifdef CONFIG_KEXEC_FILE
-static int kexec_calculate_store_digests(struct kimage *image);
-#endif
/* Location of the reserved area for the crash kernel */
struct resource crashk_res = {
@@ -146,8 +138,6 @@ int kexec_should_crash(struct task_struct *p)
*/
#define KIMAGE_NO_DEST (-1UL)
-static int kimage_is_destination_range(struct kimage *image,
- unsigned long start, unsigned long end);
static struct page *kimage_alloc_page(struct kimage *image,
gfp_t gfp_mask,
unsigned long dest);
@@ -169,7 +159,7 @@ static int copy_user_segment_list(struct kimage *image,
return ret;
}
-static int sanity_check_segment_list(struct kimage *image)
+int sanity_check_segment_list(struct kimage *image)
{
int result, i;
unsigned long nr_segments = image->nr_segments;
@@ -259,7 +249,7 @@ static int sanity_check_segment_list(struct kimage *image)
return 0;
}
-static struct kimage *do_kimage_alloc_init(void)
+struct kimage *do_kimage_alloc_init(void)
{
struct kimage *image;
@@ -286,8 +276,6 @@ static struct kimage *do_kimage_alloc_init(void)
return image;
}
-static void kimage_free_page_list(struct list_head *list);
-
static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
unsigned long nr_segments,
struct kexec_segment __user *segments,
@@ -354,283 +342,7 @@ out_free_image:
return ret;
}
-#ifdef CONFIG_KEXEC_FILE
-static int copy_file_from_fd(int fd, void **buf, unsigned long *buf_len)
-{
- struct fd f = fdget(fd);
- int ret;
- struct kstat stat;
- loff_t pos;
- ssize_t bytes = 0;
-
- if (!f.file)
- return -EBADF;
-
- ret = vfs_getattr(&f.file->f_path, &stat);
- if (ret)
- goto out;
-
- if (stat.size > INT_MAX) {
- ret = -EFBIG;
- goto out;
- }
-
- /* Don't hand 0 to vmalloc, it whines. */
- if (stat.size == 0) {
- ret = -EINVAL;
- goto out;
- }
-
- *buf = vmalloc(stat.size);
- if (!*buf) {
- ret = -ENOMEM;
- goto out;
- }
-
- pos = 0;
- while (pos < stat.size) {
- bytes = kernel_read(f.file, pos, (char *)(*buf) + pos,
- stat.size - pos);
- if (bytes < 0) {
- vfree(*buf);
- ret = bytes;
- goto out;
- }
-
- if (bytes == 0)
- break;
- pos += bytes;
- }
-
- if (pos != stat.size) {
- ret = -EBADF;
- vfree(*buf);
- goto out;
- }
-
- *buf_len = pos;
-out:
- fdput(f);
- return ret;
-}
-
-/* Architectures can provide this probe function */
-int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
- unsigned long buf_len)
-{
- return -ENOEXEC;
-}
-
-void * __weak arch_kexec_kernel_image_load(struct kimage *image)
-{
- return ERR_PTR(-ENOEXEC);
-}
-
-void __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
-{
-}
-
-int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
- unsigned long buf_len)
-{
- return -EKEYREJECTED;
-}
-
-/* Apply relocations of type RELA */
-int __weak
-arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
- unsigned int relsec)
-{
- pr_err("RELA relocation unsupported.\n");
- return -ENOEXEC;
-}
-
-/* Apply relocations of type REL */
-int __weak
-arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
- unsigned int relsec)
-{
- pr_err("REL relocation unsupported.\n");
- return -ENOEXEC;
-}
-
-/*
- * Free up memory used by kernel, initrd, and command line. This is temporary
- * memory allocation which is not needed any more after these buffers have
- * been loaded into separate segments and have been copied elsewhere.
- */
-static void kimage_file_post_load_cleanup(struct kimage *image)
-{
- struct purgatory_info *pi = &image->purgatory_info;
-
- vfree(image->kernel_buf);
- image->kernel_buf = NULL;
-
- vfree(image->initrd_buf);
- image->initrd_buf = NULL;
-
- kfree(image->cmdline_buf);
- image->cmdline_buf = NULL;
-
- vfree(pi->purgatory_buf);
- pi->purgatory_buf = NULL;
-
- vfree(pi->sechdrs);
- pi->sechdrs = NULL;
-
- /* See if architecture has anything to cleanup post load */
- arch_kimage_file_post_load_cleanup(image);
-
- /*
- * Above call should have called into bootloader to free up
- * any data stored in kimage->image_loader_data. It should
- * be ok now to free it up.
- */
- kfree(image->image_loader_data);
- image->image_loader_data = NULL;
-}
-
-/*
- * In file mode list of segments is prepared by kernel. Copy relevant
- * data from user space, do error checking, prepare segment list
- */
-static int
-kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
- const char __user *cmdline_ptr,
- unsigned long cmdline_len, unsigned flags)
-{
- int ret = 0;
- void *ldata;
-
- ret = copy_file_from_fd(kernel_fd, &image->kernel_buf,
- &image->kernel_buf_len);
- if (ret)
- return ret;
-
- /* Call arch image probe handlers */
- ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
- image->kernel_buf_len);
-
- if (ret)
- goto out;
-
-#ifdef CONFIG_KEXEC_VERIFY_SIG
- ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
- image->kernel_buf_len);
- if (ret) {
- pr_debug("kernel signature verification failed.\n");
- goto out;
- }
- pr_debug("kernel signature verification successful.\n");
-#endif
- /* It is possible that there no initramfs is being loaded */
- if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
- ret = copy_file_from_fd(initrd_fd, &image->initrd_buf,
- &image->initrd_buf_len);
- if (ret)
- goto out;
- }
-
- if (cmdline_len) {
- image->cmdline_buf = kzalloc(cmdline_len, GFP_KERNEL);
- if (!image->cmdline_buf) {
- ret = -ENOMEM;
- goto out;
- }
-
- ret = copy_from_user(image->cmdline_buf, cmdline_ptr,
- cmdline_len);
- if (ret) {
- ret = -EFAULT;
- goto out;
- }
-
- image->cmdline_buf_len = cmdline_len;
-
- /* command line should be a string with last byte null */
- if (image->cmdline_buf[cmdline_len - 1] != '\0') {
- ret = -EINVAL;
- goto out;
- }
- }
-
- /* Call arch image load handlers */
- ldata = arch_kexec_kernel_image_load(image);
-
- if (IS_ERR(ldata)) {
- ret = PTR_ERR(ldata);
- goto out;
- }
-
- image->image_loader_data = ldata;
-out:
- /* In case of error, free up all allocated memory in this function */
- if (ret)
- kimage_file_post_load_cleanup(image);
- return ret;
-}
-
-static int
-kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
- int initrd_fd, const char __user *cmdline_ptr,
- unsigned long cmdline_len, unsigned long flags)
-{
- int ret;
- struct kimage *image;
- bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
-
- image = do_kimage_alloc_init();
- if (!image)
- return -ENOMEM;
-
- image->file_mode = 1;
-
- if (kexec_on_panic) {
- /* Enable special crash kernel control page alloc policy. */
- image->control_page = crashk_res.start;
- image->type = KEXEC_TYPE_CRASH;
- }
-
- ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
- cmdline_ptr, cmdline_len, flags);
- if (ret)
- goto out_free_image;
-
- ret = sanity_check_segment_list(image);
- if (ret)
- goto out_free_post_load_bufs;
-
- ret = -ENOMEM;
- image->control_code_page = kimage_alloc_control_pages(image,
- get_order(KEXEC_CONTROL_PAGE_SIZE));
- if (!image->control_code_page) {
- pr_err("Could not allocate control_code_buffer\n");
- goto out_free_post_load_bufs;
- }
-
- if (!kexec_on_panic) {
- image->swap_page = kimage_alloc_control_pages(image, 0);
- if (!image->swap_page) {
- pr_err("Could not allocate swap buffer\n");
- goto out_free_control_pages;
- }
- }
-
- *rimage = image;
- return 0;
-out_free_control_pages:
- kimage_free_page_list(&image->control_pages);
-out_free_post_load_bufs:
- kimage_file_post_load_cleanup(image);
-out_free_image:
- kfree(image);
- return ret;
-}
-#else /* CONFIG_KEXEC_FILE */
-static inline void kimage_file_post_load_cleanup(struct kimage *image) { }
-#endif /* CONFIG_KEXEC_FILE */
-
-static int kimage_is_destination_range(struct kimage *image,
+int kimage_is_destination_range(struct kimage *image,
unsigned long start,
unsigned long end)
{
@@ -676,7 +388,7 @@ static void kimage_free_pages(struct page *page)
__free_pages(page, order);
}
-static void kimage_free_page_list(struct list_head *list)
+void kimage_free_page_list(struct list_head *list)
{
struct list_head *pos, *next;
@@ -892,7 +604,7 @@ static void kimage_free_extra_pages(struct kimage *image)
kimage_free_page_list(&image->unusable_pages);
}
-static void kimage_terminate(struct kimage *image)
+void kimage_terminate(struct kimage *image)
{
if (*image->entry != 0)
image->entry++;
@@ -913,7 +625,7 @@ static void kimage_free_entry(kimage_entry_t entry)
kimage_free_pages(page);
}
-static void kimage_free(struct kimage *image)
+void kimage_free(struct kimage *image)
{
kimage_entry_t *ptr, entry;
kimage_entry_t ind = 0;
@@ -1204,7 +916,7 @@ out:
return result;
}
-static int kimage_load_segment(struct kimage *image,
+int kimage_load_segment(struct kimage *image,
struct kexec_segment *segment)
{
int result = -ENOMEM;
@@ -1245,8 +957,6 @@ struct kimage *kexec_image;
struct kimage *kexec_crash_image;
int kexec_load_disabled;
-static DEFINE_MUTEX(kexec_mutex);
-
SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
struct kexec_segment __user *, segments, unsigned long, flags)
{
@@ -1391,85 +1101,6 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
}
#endif
-#ifdef CONFIG_KEXEC_FILE
-SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
- unsigned long, cmdline_len, const char __user *, cmdline_ptr,
- unsigned long, flags)
-{
- int ret = 0, i;
- struct kimage **dest_image, *image;
-
- /* We only trust the superuser with rebooting the system. */
- if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
- return -EPERM;
-
- /* Make sure we have a legal set of flags */
- if (flags != (flags & KEXEC_FILE_FLAGS))
- return -EINVAL;
-
- image = NULL;
-
- if (!mutex_trylock(&kexec_mutex))
- return -EBUSY;
-
- dest_image = &kexec_image;
- if (flags & KEXEC_FILE_ON_CRASH)
- dest_image = &kexec_crash_image;
-
- if (flags & KEXEC_FILE_UNLOAD)
- goto exchange;
-
- /*
- * In case of crash, new kernel gets loaded in reserved region. It is
- * same memory where old crash kernel might be loaded. Free any
- * current crash dump kernel before we corrupt it.
- */
- if (flags & KEXEC_FILE_ON_CRASH)
- kimage_free(xchg(&kexec_crash_image, NULL));
-
- ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
- cmdline_len, flags);
- if (ret)
- goto out;
-
- ret = machine_kexec_prepare(image);
- if (ret)
- goto out;
-
- ret = kexec_calculate_store_digests(image);
- if (ret)
- goto out;
-
- for (i = 0; i < image->nr_segments; i++) {
- struct kexec_segment *ksegment;
-
- ksegment = &image->segment[i];
- pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
- i, ksegment->buf, ksegment->bufsz, ksegment->mem,
- ksegment->memsz);
-
- ret = kimage_load_segment(image, &image->segment[i]);
- if (ret)
- goto out;
- }
-
- kimage_terminate(image);
-
- /*
- * Free up any temporary buffers allocated which are not needed
- * after image has been loaded
- */
- kimage_file_post_load_cleanup(image);
-exchange:
- image = xchg(dest_image, image);
-out:
- mutex_unlock(&kexec_mutex);
- kimage_free(image);
- return ret;
-}
-
-#endif /* CONFIG_KEXEC_FILE */
-
void crash_kexec(struct pt_regs *regs)
{
/* Take the kexec_mutex here to prevent sys_kexec_load
@@ -2024,672 +1655,6 @@ static int __init crash_save_vmcoreinfo_init(void)
subsys_initcall(crash_save_vmcoreinfo_init);
-#ifdef CONFIG_KEXEC_FILE
-static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
- struct kexec_buf *kbuf)
-{
- struct kimage *image = kbuf->image;
- unsigned long temp_start, temp_end;
-
- temp_end = min(end, kbuf->buf_max);
- temp_start = temp_end - kbuf->memsz;
-
- do {
- /* align down start */
- temp_start = temp_start & (~(kbuf->buf_align - 1));
-
- if (temp_start < start || temp_start < kbuf->buf_min)
- return 0;
-
- temp_end = temp_start + kbuf->memsz - 1;
-
- /*
- * Make sure this does not conflict with any of existing
- * segments
- */
- if (kimage_is_destination_range(image, temp_start, temp_end)) {
- temp_start = temp_start - PAGE_SIZE;
- continue;
- }
-
- /* We found a suitable memory range */
- break;
- } while (1);
-
- /* If we are here, we found a suitable memory range */
- kbuf->mem = temp_start;
-
- /* Success, stop navigating through remaining System RAM ranges */
- return 1;
-}
-
-static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
- struct kexec_buf *kbuf)
-{
- struct kimage *image = kbuf->image;
- unsigned long temp_start, temp_end;
-
- temp_start = max(start, kbuf->buf_min);
-
- do {
- temp_start = ALIGN(temp_start, kbuf->buf_align);
- temp_end = temp_start + kbuf->memsz - 1;
-
- if (temp_end > end || temp_end > kbuf->buf_max)
- return 0;
- /*
- * Make sure this does not conflict with any of existing
- * segments
- */
- if (kimage_is_destination_range(image, temp_start, temp_end)) {
- temp_start = temp_start + PAGE_SIZE;
- continue;
- }
-
- /* We found a suitable memory range */
- break;
- } while (1);
-
- /* If we are here, we found a suitable memory range */
- kbuf->mem = temp_start;
-
- /* Success, stop navigating through remaining System RAM ranges */
- return 1;
-}
-
-static int locate_mem_hole_callback(u64 start, u64 end, void *arg)
-{
- struct kexec_buf *kbuf = (struct kexec_buf *)arg;
- unsigned long sz = end - start + 1;
-
- /* Returning 0 will take to next memory range */
- if (sz < kbuf->memsz)
- return 0;
-
- if (end < kbuf->buf_min || start > kbuf->buf_max)
- return 0;
-
- /*
- * Allocate memory top down with-in ram range. Otherwise bottom up
- * allocation.
- */
- if (kbuf->top_down)
- return locate_mem_hole_top_down(start, end, kbuf);
- return locate_mem_hole_bottom_up(start, end, kbuf);
-}
-
-/*
- * Helper function for placing a buffer in a kexec segment. This assumes
- * that kexec_mutex is held.
- */
-int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
- unsigned long memsz, unsigned long buf_align,
- unsigned long buf_min, unsigned long buf_max,
- bool top_down, unsigned long *load_addr)
-{
-
- struct kexec_segment *ksegment;
- struct kexec_buf buf, *kbuf;
- int ret;
-
- /* Currently adding segment this way is allowed only in file mode */
- if (!image->file_mode)
- return -EINVAL;
-
- if (image->nr_segments >= KEXEC_SEGMENT_MAX)
- return -EINVAL;
-
- /*
- * Make sure we are not trying to add buffer after allocating
- * control pages. All segments need to be placed first before
- * any control pages are allocated. As control page allocation
- * logic goes through list of segments to make sure there are
- * no destination overlaps.
- */
- if (!list_empty(&image->control_pages)) {
- WARN_ON(1);
- return -EINVAL;
- }
-
- memset(&buf, 0, sizeof(struct kexec_buf));
- kbuf = &buf;
- kbuf->image = image;
- kbuf->buffer = buffer;
- kbuf->bufsz = bufsz;
-
- kbuf->memsz = ALIGN(memsz, PAGE_SIZE);
- kbuf->buf_align = max(buf_align, PAGE_SIZE);
- kbuf->buf_min = buf_min;
- kbuf->buf_max = buf_max;
- kbuf->top_down = top_down;
-
- /* Walk the RAM ranges and allocate a suitable range for the buffer */
- if (image->type == KEXEC_TYPE_CRASH)
- ret = walk_iomem_res("Crash kernel",
- IORESOURCE_MEM | IORESOURCE_BUSY,
- crashk_res.start, crashk_res.end, kbuf,
- locate_mem_hole_callback);
- else
- ret = walk_system_ram_res(0, -1, kbuf,
- locate_mem_hole_callback);
- if (ret != 1) {
- /* A suitable memory range could not be found for buffer */
- return -EADDRNOTAVAIL;
- }
-
- /* Found a suitable memory range */
- ksegment = &image->segment[image->nr_segments];
- ksegment->kbuf = kbuf->buffer;
- ksegment->bufsz = kbuf->bufsz;
- ksegment->mem = kbuf->mem;
- ksegment->memsz = kbuf->memsz;
- image->nr_segments++;
- *load_addr = ksegment->mem;
- return 0;
-}
-
-/* Calculate and store the digest of segments */
-static int kexec_calculate_store_digests(struct kimage *image)
-{
- struct crypto_shash *tfm;
- struct shash_desc *desc;
- int ret = 0, i, j, zero_buf_sz, sha_region_sz;
- size_t desc_size, nullsz;
- char *digest;
- void *zero_buf;
- struct kexec_sha_region *sha_regions;
- struct purgatory_info *pi = &image->purgatory_info;
-
- zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
- zero_buf_sz = PAGE_SIZE;
-
- tfm = crypto_alloc_shash("sha256", 0, 0);
- if (IS_ERR(tfm)) {
- ret = PTR_ERR(tfm);
- goto out;
- }
-
- desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
- desc = kzalloc(desc_size, GFP_KERNEL);
- if (!desc) {
- ret = -ENOMEM;
- goto out_free_tfm;
- }
-
- sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
- sha_regions = vzalloc(sha_region_sz);
- if (!sha_regions)
- goto out_free_desc;
-
- desc->tfm = tfm;
- desc->flags = 0;
-
- ret = crypto_shash_init(desc);
- if (ret < 0)
- goto out_free_sha_regions;
-
- digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
- if (!digest) {
- ret = -ENOMEM;
- goto out_free_sha_regions;
- }
-
- for (j = i = 0; i < image->nr_segments; i++) {
- struct kexec_segment *ksegment;
-
- ksegment = &image->segment[i];
- /*
- * Skip purgatory as it will be modified once we put digest
- * info in purgatory.
- */
- if (ksegment->kbuf == pi->purgatory_buf)
- continue;
-
- ret = crypto_shash_update(desc, ksegment->kbuf,
- ksegment->bufsz);
- if (ret)
- break;
-
- /*
- * Assume rest of the buffer is filled with zero and
- * update digest accordingly.
- */
- nullsz = ksegment->memsz - ksegment->bufsz;
- while (nullsz) {
- unsigned long bytes = nullsz;
-
- if (bytes > zero_buf_sz)
- bytes = zero_buf_sz;
- ret = crypto_shash_update(desc, zero_buf, bytes);
- if (ret)
- break;
- nullsz -= bytes;
- }
-
- if (ret)
- break;
-
- sha_regions[j].start = ksegment->mem;
- sha_regions[j].len = ksegment->memsz;
- j++;
- }
-
- if (!ret) {
- ret = crypto_shash_final(desc, digest);
- if (ret)
- goto out_free_digest;
- ret = kexec_purgatory_get_set_symbol(image, "sha_regions",
- sha_regions, sha_region_sz, 0);
- if (ret)
- goto out_free_digest;
-
- ret = kexec_purgatory_get_set_symbol(image, "sha256_digest",
- digest, SHA256_DIGEST_SIZE, 0);
- if (ret)
- goto out_free_digest;
- }
-
-out_free_digest:
- kfree(digest);
-out_free_sha_regions:
- vfree(sha_regions);
-out_free_desc:
- kfree(desc);
-out_free_tfm:
- kfree(tfm);
-out:
- return ret;
-}
-
-/* Actually load purgatory. Lot of code taken from kexec-tools */
-static int __kexec_load_purgatory(struct kimage *image, unsigned long min,
- unsigned long max, int top_down)
-{
- struct purgatory_info *pi = &image->purgatory_info;
- unsigned long align, buf_align, bss_align, buf_sz, bss_sz, bss_pad;
- unsigned long memsz, entry, load_addr, curr_load_addr, bss_addr, offset;
- unsigned char *buf_addr, *src;
- int i, ret = 0, entry_sidx = -1;
- const Elf_Shdr *sechdrs_c;
- Elf_Shdr *sechdrs = NULL;
- void *purgatory_buf = NULL;
-
- /*
- * sechdrs_c points to section headers in purgatory and are read
- * only. No modifications allowed.
- */
- sechdrs_c = (void *)pi->ehdr + pi->ehdr->e_shoff;
-
- /*
- * We can not modify sechdrs_c[] and its fields. It is read only.
- * Copy it over to a local copy where one can store some temporary
- * data and free it at the end. We need to modify ->sh_addr and
- * ->sh_offset fields to keep track of permanent and temporary
- * locations of sections.
- */
- sechdrs = vzalloc(pi->ehdr->e_shnum * sizeof(Elf_Shdr));
- if (!sechdrs)
- return -ENOMEM;
-
- memcpy(sechdrs, sechdrs_c, pi->ehdr->e_shnum * sizeof(Elf_Shdr));
-
- /*
- * We seem to have multiple copies of sections. First copy is which
- * is embedded in kernel in read only section. Some of these sections
- * will be copied to a temporary buffer and relocated. And these
- * sections will finally be copied to their final destination at
- * segment load time.
- *
- * Use ->sh_offset to reflect section address in memory. It will
- * point to original read only copy if section is not allocatable.
- * Otherwise it will point to temporary copy which will be relocated.
- *
- * Use ->sh_addr to contain final address of the section where it
- * will go during execution time.
- */
- for (i = 0; i < pi->ehdr->e_shnum; i++) {
- if (sechdrs[i].sh_type == SHT_NOBITS)
- continue;
-
- sechdrs[i].sh_offset = (unsigned long)pi->ehdr +
- sechdrs[i].sh_offset;
- }
-
- /*
- * Identify entry point section and make entry relative to section
- * start.
- */
- entry = pi->ehdr->e_entry;
- for (i = 0; i < pi->ehdr->e_shnum; i++) {
- if (!(sechdrs[i].sh_flags & SHF_ALLOC))
- continue;
-
- if (!(sechdrs[i].sh_flags & SHF_EXECINSTR))
- continue;
-
- /* Make entry section relative */
- if (sechdrs[i].sh_addr <= pi->ehdr->e_entry &&
- ((sechdrs[i].sh_addr + sechdrs[i].sh_size) >
- pi->ehdr->e_entry)) {
- entry_sidx = i;
- entry -= sechdrs[i].sh_addr;
- break;
- }
- }
-
- /* Determine how much memory is needed to load relocatable object. */
- buf_align = 1;
- bss_align = 1;
- buf_sz = 0;
- bss_sz = 0;
-
- for (i = 0; i < pi->ehdr->e_shnum; i++) {
- if (!(sechdrs[i].sh_flags & SHF_ALLOC))
- continue;
-
- align = sechdrs[i].sh_addralign;
- if (sechdrs[i].sh_type != SHT_NOBITS) {
- if (buf_align < align)
- buf_align = align;
- buf_sz = ALIGN(buf_sz, align);
- buf_sz += sechdrs[i].sh_size;
- } else {
- /* bss section */
- if (bss_align < align)
- bss_align = align;
- bss_sz = ALIGN(bss_sz, align);
- bss_sz += sechdrs[i].sh_size;
- }
- }
-
- /* Determine the bss padding required to align bss properly */
- bss_pad = 0;
- if (buf_sz & (bss_align - 1))
- bss_pad = bss_align - (buf_sz & (bss_align - 1));
-
- memsz = buf_sz + bss_pad + bss_sz;
-
- /* Allocate buffer for purgatory */
- purgatory_buf = vzalloc(buf_sz);
- if (!purgatory_buf) {
- ret = -ENOMEM;
- goto out;
- }
-
- if (buf_align < bss_align)
- buf_align = bss_align;
-
- /* Add buffer to segment list */
- ret = kexec_add_buffer(image, purgatory_buf, buf_sz, memsz,
- buf_align, min, max, top_down,
- &pi->purgatory_load_addr);
- if (ret)
- goto out;
-
- /* Load SHF_ALLOC sections */
- buf_addr = purgatory_buf;
- load_addr = curr_load_addr = pi->purgatory_load_addr;
- bss_addr = load_addr + buf_sz + bss_pad;
-
- for (i = 0; i < pi->ehdr->e_shnum; i++) {
- if (!(sechdrs[i].sh_flags & SHF_ALLOC))
- continue;
-
- align = sechdrs[i].sh_addralign;
- if (sechdrs[i].sh_type != SHT_NOBITS) {
- curr_load_addr = ALIGN(curr_load_addr, align);
- offset = curr_load_addr - load_addr;
- /* We already modifed ->sh_offset to keep src addr */
- src = (char *) sechdrs[i].sh_offset;
- memcpy(buf_addr + offset, src, sechdrs[i].sh_size);
-
- /* Store load address and source address of section */
- sechdrs[i].sh_addr = curr_load_addr;
-
- /*
- * This section got copied to temporary buffer. Update
- * ->sh_offset accordingly.
- */
- sechdrs[i].sh_offset = (unsigned long)(buf_addr + offset);
-
- /* Advance to the next address */
- curr_load_addr += sechdrs[i].sh_size;
- } else {
- bss_addr = ALIGN(bss_addr, align);
- sechdrs[i].sh_addr = bss_addr;
- bss_addr += sechdrs[i].sh_size;
- }
- }
-
- /* Update entry point based on load address of text section */
- if (entry_sidx >= 0)
- entry += sechdrs[entry_sidx].sh_addr;
-
- /* Make kernel jump to purgatory after shutdown */
- image->start = entry;
-
- /* Used later to get/set symbol values */
- pi->sechdrs = sechdrs;
-
- /*
- * Used later to identify which section is purgatory and skip it
- * from checksumming.
- */
- pi->purgatory_buf = purgatory_buf;
- return ret;
-out:
- vfree(sechdrs);
- vfree(purgatory_buf);
- return ret;
-}
-
-static int kexec_apply_relocations(struct kimage *image)
-{
- int i, ret;
- struct purgatory_info *pi = &image->purgatory_info;
- Elf_Shdr *sechdrs = pi->sechdrs;
-
- /* Apply relocations */
- for (i = 0; i < pi->ehdr->e_shnum; i++) {
- Elf_Shdr *section, *symtab;
-
- if (sechdrs[i].sh_type != SHT_RELA &&
- sechdrs[i].sh_type != SHT_REL)
- continue;
-
- /*
- * For section of type SHT_RELA/SHT_REL,
- * ->sh_link contains section header index of associated
- * symbol table. And ->sh_info contains section header
- * index of section to which relocations apply.
- */
- if (sechdrs[i].sh_info >= pi->ehdr->e_shnum ||
- sechdrs[i].sh_link >= pi->ehdr->e_shnum)
- return -ENOEXEC;
-
- section = &sechdrs[sechdrs[i].sh_info];
- symtab = &sechdrs[sechdrs[i].sh_link];
-
- if (!(section->sh_flags & SHF_ALLOC))
- continue;
-
- /*
- * symtab->sh_link contain section header index of associated
- * string table.
- */
- if (symtab->sh_link >= pi->ehdr->e_shnum)
- /* Invalid section number? */
- continue;
-
- /*
- * Respective architecture needs to provide support for applying
- * relocations of type SHT_RELA/SHT_REL.
- */
- if (sechdrs[i].sh_type == SHT_RELA)
- ret = arch_kexec_apply_relocations_add(pi->ehdr,
- sechdrs, i);
- else if (sechdrs[i].sh_type == SHT_REL)
- ret = arch_kexec_apply_relocations(pi->ehdr,
- sechdrs, i);
- if (ret)
- return ret;
- }
-
- return 0;
-}
-
-/* Load relocatable purgatory object and relocate it appropriately */
-int kexec_load_purgatory(struct kimage *image, unsigned long min,
- unsigned long max, int top_down,
- unsigned long *load_addr)
-{
- struct purgatory_info *pi = &image->purgatory_info;
- int ret;
-
- if (kexec_purgatory_size <= 0)
- return -EINVAL;
-
- if (kexec_purgatory_size < sizeof(Elf_Ehdr))
- return -ENOEXEC;
-
- pi->ehdr = (Elf_Ehdr *)kexec_purgatory;
-
- if (memcmp(pi->ehdr->e_ident, ELFMAG, SELFMAG) != 0
- || pi->ehdr->e_type != ET_REL
- || !elf_check_arch(pi->ehdr)
- || pi->ehdr->e_shentsize != sizeof(Elf_Shdr))
- return -ENOEXEC;
-
- if (pi->ehdr->e_shoff >= kexec_purgatory_size
- || (pi->ehdr->e_shnum * sizeof(Elf_Shdr) >
- kexec_purgatory_size - pi->ehdr->e_shoff))
- return -ENOEXEC;
-
- ret = __kexec_load_purgatory(image, min, max, top_down);
- if (ret)
- return ret;
-
- ret = kexec_apply_relocations(image);
- if (ret)
- goto out;
-
- *load_addr = pi->purgatory_load_addr;
- return 0;
-out:
- vfree(pi->sechdrs);
- vfree(pi->purgatory_buf);
- return ret;
-}
-
-static Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
- const char *name)
-{
- Elf_Sym *syms;
- Elf_Shdr *sechdrs;
- Elf_Ehdr *ehdr;
- int i, k;
- const char *strtab;
-
- if (!pi->sechdrs || !pi->ehdr)
- return NULL;
-
- sechdrs = pi->sechdrs;
- ehdr = pi->ehdr;
-
- for (i = 0; i < ehdr->e_shnum; i++) {
- if (sechdrs[i].sh_type != SHT_SYMTAB)
- continue;
-
- if (sechdrs[i].sh_link >= ehdr->e_shnum)
- /* Invalid strtab section number */
- continue;
- strtab = (char *)sechdrs[sechdrs[i].sh_link].sh_offset;
- syms = (Elf_Sym *)sechdrs[i].sh_offset;
-
- /* Go through symbols for a match */
- for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
- if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
- continue;
-
- if (strcmp(strtab + syms[k].st_name, name) != 0)
- continue;
-
- if (syms[k].st_shndx == SHN_UNDEF ||
- syms[k].st_shndx >= ehdr->e_shnum) {
- pr_debug("Symbol: %s has bad section index %d.\n",
- name, syms[k].st_shndx);
- return NULL;
- }
-
- /* Found the symbol we are looking for */
- return &syms[k];
- }
- }
-
- return NULL;
-}
-
-void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
-{
- struct purgatory_info *pi = &image->purgatory_info;
- Elf_Sym *sym;
- Elf_Shdr *sechdr;
-
- sym = kexec_purgatory_find_symbol(pi, name);
- if (!sym)
- return ERR_PTR(-EINVAL);
-
- sechdr = &pi->sechdrs[sym->st_shndx];
-
- /*
- * Returns the address where symbol will finally be loaded after
- * kexec_load_segment()
- */
- return (void *)(sechdr->sh_addr + sym->st_value);
-}
-
-/*
- * Get or set value of a symbol. If "get_value" is true, symbol value is
- * returned in buf otherwise symbol value is set based on value in buf.
- */
-int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
- void *buf, unsigned int size, bool get_value)
-{
- Elf_Sym *sym;
- Elf_Shdr *sechdrs;
- struct purgatory_info *pi = &image->purgatory_info;
- char *sym_buf;
-
- sym = kexec_purgatory_find_symbol(pi, name);
- if (!sym)
- return -EINVAL;
-
- if (sym->st_size != size) {
- pr_err("symbol %s size mismatch: expected %lu actual %u\n",
- name, (unsigned long)sym->st_size, size);
- return -EINVAL;
- }
-
- sechdrs = pi->sechdrs;
-
- if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
- pr_err("symbol %s is in a bss section. Cannot %s\n", name,
- get_value ? "get" : "set");
- return -EINVAL;
- }
-
- sym_buf = (unsigned char *)sechdrs[sym->st_shndx].sh_offset +
- sym->st_value;
-
- if (get_value)
- memcpy((void *)buf, sym_buf, size);
- else
- memcpy((void *)sym_buf, buf, size);
-
- return 0;
-}
-#endif /* CONFIG_KEXEC_FILE */
-
/*
* Move into place and start executing a preloaded standalone
* executable. If nothing was preloaded return an error.
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
new file mode 100644
index 0000000..82b443e
--- /dev/null
+++ b/kernel/kexec_file.c
@@ -0,0 +1,1044 @@
+/*
+ * kexec: kexec_file_load system call
+ *
+ * Copyright (C) 2014 Red Hat Inc.
+ * Authors:
+ * Vivek Goyal <vgoyal@redhat.com>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include <linux/capability.h>
+#include <linux/mm.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/kexec.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include <linux/syscalls.h>
+#include <linux/vmalloc.h>
+#include "kexec_internal.h"
+
+/*
+ * Declare these symbols weak so that if architecture provides a purgatory,
+ * these will be overridden.
+ */
+char __weak kexec_purgatory[0];
+size_t __weak kexec_purgatory_size = 0;
+
+static int kexec_calculate_store_digests(struct kimage *image);
+
+static int copy_file_from_fd(int fd, void **buf, unsigned long *buf_len)
+{
+ struct fd f = fdget(fd);
+ int ret;
+ struct kstat stat;
+ loff_t pos;
+ ssize_t bytes = 0;
+
+ if (!f.file)
+ return -EBADF;
+
+ ret = vfs_getattr(&f.file->f_path, &stat);
+ if (ret)
+ goto out;
+
+ if (stat.size > INT_MAX) {
+ ret = -EFBIG;
+ goto out;
+ }
+
+ /* Don't hand 0 to vmalloc, it whines. */
+ if (stat.size == 0) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ *buf = vmalloc(stat.size);
+ if (!*buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ pos = 0;
+ while (pos < stat.size) {
+ bytes = kernel_read(f.file, pos, (char *)(*buf) + pos,
+ stat.size - pos);
+ if (bytes < 0) {
+ vfree(*buf);
+ ret = bytes;
+ goto out;
+ }
+
+ if (bytes == 0)
+ break;
+ pos += bytes;
+ }
+
+ if (pos != stat.size) {
+ ret = -EBADF;
+ vfree(*buf);
+ goto out;
+ }
+
+ *buf_len = pos;
+out:
+ fdput(f);
+ return ret;
+}
+
+/* Architectures can provide this probe function */
+int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
+ unsigned long buf_len)
+{
+ return -ENOEXEC;
+}
+
+void * __weak arch_kexec_kernel_image_load(struct kimage *image)
+{
+ return ERR_PTR(-ENOEXEC);
+}
+
+void __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
+{
+}
+
+int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
+ unsigned long buf_len)
+{
+ return -EKEYREJECTED;
+}
+
+/* Apply relocations of type RELA */
+int __weak
+arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
+ unsigned int relsec)
+{
+ pr_err("RELA relocation unsupported.\n");
+ return -ENOEXEC;
+}
+
+/* Apply relocations of type REL */
+int __weak
+arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
+ unsigned int relsec)
+{
+ pr_err("REL relocation unsupported.\n");
+ return -ENOEXEC;
+}
+
+/*
+ * Free up memory used by kernel, initrd, and command line. This is temporary
+ * memory allocation which is not needed any more after these buffers have
+ * been loaded into separate segments and have been copied elsewhere.
+ */
+void kimage_file_post_load_cleanup(struct kimage *image)
+{
+ struct purgatory_info *pi = &image->purgatory_info;
+
+ vfree(image->kernel_buf);
+ image->kernel_buf = NULL;
+
+ vfree(image->initrd_buf);
+ image->initrd_buf = NULL;
+
+ kfree(image->cmdline_buf);
+ image->cmdline_buf = NULL;
+
+ vfree(pi->purgatory_buf);
+ pi->purgatory_buf = NULL;
+
+ vfree(pi->sechdrs);
+ pi->sechdrs = NULL;
+
+ /* See if architecture has anything to cleanup post load */
+ arch_kimage_file_post_load_cleanup(image);
+
+ /*
+ * Above call should have called into bootloader to free up
+ * any data stored in kimage->image_loader_data. It should
+ * be ok now to free it up.
+ */
+ kfree(image->image_loader_data);
+ image->image_loader_data = NULL;
+}
+
+/*
+ * In file mode list of segments is prepared by kernel. Copy relevant
+ * data from user space, do error checking, prepare segment list
+ */
+static int
+kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
+ const char __user *cmdline_ptr,
+ unsigned long cmdline_len, unsigned flags)
+{
+ int ret = 0;
+ void *ldata;
+
+ ret = copy_file_from_fd(kernel_fd, &image->kernel_buf,
+ &image->kernel_buf_len);
+ if (ret)
+ return ret;
+
+ /* Call arch image probe handlers */
+ ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
+ image->kernel_buf_len);
+
+ if (ret)
+ goto out;
+
+#ifdef CONFIG_KEXEC_VERIFY_SIG
+ ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
+ image->kernel_buf_len);
+ if (ret) {
+ pr_debug("kernel signature verification failed.\n");
+ goto out;
+ }
+ pr_debug("kernel signature verification successful.\n");
+#endif
+ /* It is possible that there no initramfs is being loaded */
+ if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
+ ret = copy_file_from_fd(initrd_fd, &image->initrd_buf,
+ &image->initrd_buf_len);
+ if (ret)
+ goto out;
+ }
+
+ if (cmdline_len) {
+ image->cmdline_buf = kzalloc(cmdline_len, GFP_KERNEL);
+ if (!image->cmdline_buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = copy_from_user(image->cmdline_buf, cmdline_ptr,
+ cmdline_len);
+ if (ret) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ image->cmdline_buf_len = cmdline_len;
+
+ /* command line should be a string with last byte null */
+ if (image->cmdline_buf[cmdline_len - 1] != '\0') {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ /* Call arch image load handlers */
+ ldata = arch_kexec_kernel_image_load(image);
+
+ if (IS_ERR(ldata)) {
+ ret = PTR_ERR(ldata);
+ goto out;
+ }
+
+ image->image_loader_data = ldata;
+out:
+ /* In case of error, free up all allocated memory in this function */
+ if (ret)
+ kimage_file_post_load_cleanup(image);
+ return ret;
+}
+
+static int
+kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
+ int initrd_fd, const char __user *cmdline_ptr,
+ unsigned long cmdline_len, unsigned long flags)
+{
+ int ret;
+ struct kimage *image;
+ bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
+
+ image = do_kimage_alloc_init();
+ if (!image)
+ return -ENOMEM;
+
+ image->file_mode = 1;
+
+ if (kexec_on_panic) {
+ /* Enable special crash kernel control page alloc policy. */
+ image->control_page = crashk_res.start;
+ image->type = KEXEC_TYPE_CRASH;
+ }
+
+ ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
+ cmdline_ptr, cmdline_len, flags);
+ if (ret)
+ goto out_free_image;
+
+ ret = sanity_check_segment_list(image);
+ if (ret)
+ goto out_free_post_load_bufs;
+
+ ret = -ENOMEM;
+ image->control_code_page = kimage_alloc_control_pages(image,
+ get_order(KEXEC_CONTROL_PAGE_SIZE));
+ if (!image->control_code_page) {
+ pr_err("Could not allocate control_code_buffer\n");
+ goto out_free_post_load_bufs;
+ }
+
+ if (!kexec_on_panic) {
+ image->swap_page = kimage_alloc_control_pages(image, 0);
+ if (!image->swap_page) {
+ pr_err("Could not allocate swap buffer\n");
+ goto out_free_control_pages;
+ }
+ }
+
+ *rimage = image;
+ return 0;
+out_free_control_pages:
+ kimage_free_page_list(&image->control_pages);
+out_free_post_load_bufs:
+ kimage_file_post_load_cleanup(image);
+out_free_image:
+ kfree(image);
+ return ret;
+}
+
+SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
+ unsigned long, cmdline_len, const char __user *, cmdline_ptr,
+ unsigned long, flags)
+{
+ int ret = 0, i;
+ struct kimage **dest_image, *image;
+
+ /* We only trust the superuser with rebooting the system. */
+ if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
+ return -EPERM;
+
+ /* Make sure we have a legal set of flags */
+ if (flags != (flags & KEXEC_FILE_FLAGS))
+ return -EINVAL;
+
+ image = NULL;
+
+ if (!mutex_trylock(&kexec_mutex))
+ return -EBUSY;
+
+ dest_image = &kexec_image;
+ if (flags & KEXEC_FILE_ON_CRASH)
+ dest_image = &kexec_crash_image;
+
+ if (flags & KEXEC_FILE_UNLOAD)
+ goto exchange;
+
+ /*
+ * In case of crash, new kernel gets loaded in reserved region. It is
+ * same memory where old crash kernel might be loaded. Free any
+ * current crash dump kernel before we corrupt it.
+ */
+ if (flags & KEXEC_FILE_ON_CRASH)
+ kimage_free(xchg(&kexec_crash_image, NULL));
+
+ ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
+ cmdline_len, flags);
+ if (ret)
+ goto out;
+
+ ret = machine_kexec_prepare(image);
+ if (ret)
+ goto out;
+
+ ret = kexec_calculate_store_digests(image);
+ if (ret)
+ goto out;
+
+ for (i = 0; i < image->nr_segments; i++) {
+ struct kexec_segment *ksegment;
+
+ ksegment = &image->segment[i];
+ pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
+ i, ksegment->buf, ksegment->bufsz, ksegment->mem,
+ ksegment->memsz);
+
+ ret = kimage_load_segment(image, &image->segment[i]);
+ if (ret)
+ goto out;
+ }
+
+ kimage_terminate(image);
+
+ /*
+ * Free up any temporary buffers allocated which are not needed
+ * after image has been loaded
+ */
+ kimage_file_post_load_cleanup(image);
+exchange:
+ image = xchg(dest_image, image);
+out:
+ mutex_unlock(&kexec_mutex);
+ kimage_free(image);
+ return ret;
+}
+
+static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
+ struct kexec_buf *kbuf)
+{
+ struct kimage *image = kbuf->image;
+ unsigned long temp_start, temp_end;
+
+ temp_end = min(end, kbuf->buf_max);
+ temp_start = temp_end - kbuf->memsz;
+
+ do {
+ /* align down start */
+ temp_start = temp_start & (~(kbuf->buf_align - 1));
+
+ if (temp_start < start || temp_start < kbuf->buf_min)
+ return 0;
+
+ temp_end = temp_start + kbuf->memsz - 1;
+
+ /*
+ * Make sure this does not conflict with any of existing
+ * segments
+ */
+ if (kimage_is_destination_range(image, temp_start, temp_end)) {
+ temp_start = temp_start - PAGE_SIZE;
+ continue;
+ }
+
+ /* We found a suitable memory range */
+ break;
+ } while (1);
+
+ /* If we are here, we found a suitable memory range */
+ kbuf->mem = temp_start;
+
+ /* Success, stop navigating through remaining System RAM ranges */
+ return 1;
+}
+
+static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
+ struct kexec_buf *kbuf)
+{
+ struct kimage *image = kbuf->image;
+ unsigned long temp_start, temp_end;
+
+ temp_start = max(start, kbuf->buf_min);
+
+ do {
+ temp_start = ALIGN(temp_start, kbuf->buf_align);
+ temp_end = temp_start + kbuf->memsz - 1;
+
+ if (temp_end > end || temp_end > kbuf->buf_max)
+ return 0;
+ /*
+ * Make sure this does not conflict with any of existing
+ * segments
+ */
+ if (kimage_is_destination_range(image, temp_start, temp_end)) {
+ temp_start = temp_start + PAGE_SIZE;
+ continue;
+ }
+
+ /* We found a suitable memory range */
+ break;
+ } while (1);
+
+ /* If we are here, we found a suitable memory range */
+ kbuf->mem = temp_start;
+
+ /* Success, stop navigating through remaining System RAM ranges */
+ return 1;
+}
+
+static int locate_mem_hole_callback(u64 start, u64 end, void *arg)
+{
+ struct kexec_buf *kbuf = (struct kexec_buf *)arg;
+ unsigned long sz = end - start + 1;
+
+ /* Returning 0 will take to next memory range */
+ if (sz < kbuf->memsz)
+ return 0;
+
+ if (end < kbuf->buf_min || start > kbuf->buf_max)
+ return 0;
+
+ /*
+ * Allocate memory top down with-in ram range. Otherwise bottom up
+ * allocation.
+ */
+ if (kbuf->top_down)
+ return locate_mem_hole_top_down(start, end, kbuf);
+ return locate_mem_hole_bottom_up(start, end, kbuf);
+}
+
+/*
+ * Helper function for placing a buffer in a kexec segment. This assumes
+ * that kexec_mutex is held.
+ */
+int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
+ unsigned long memsz, unsigned long buf_align,
+ unsigned long buf_min, unsigned long buf_max,
+ bool top_down, unsigned long *load_addr)
+{
+
+ struct kexec_segment *ksegment;
+ struct kexec_buf buf, *kbuf;
+ int ret;
+
+ /* Currently adding segment this way is allowed only in file mode */
+ if (!image->file_mode)
+ return -EINVAL;
+
+ if (image->nr_segments >= KEXEC_SEGMENT_MAX)
+ return -EINVAL;
+
+ /*
+ * Make sure we are not trying to add buffer after allocating
+ * control pages. All segments need to be placed first before
+ * any control pages are allocated. As control page allocation
+ * logic goes through list of segments to make sure there are
+ * no destination overlaps.
+ */
+ if (!list_empty(&image->control_pages)) {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ memset(&buf, 0, sizeof(struct kexec_buf));
+ kbuf = &buf;
+ kbuf->image = image;
+ kbuf->buffer = buffer;
+ kbuf->bufsz = bufsz;
+
+ kbuf->memsz = ALIGN(memsz, PAGE_SIZE);
+ kbuf->buf_align = max(buf_align, PAGE_SIZE);
+ kbuf->buf_min = buf_min;
+ kbuf->buf_max = buf_max;
+ kbuf->top_down = top_down;
+
+ /* Walk the RAM ranges and allocate a suitable range for the buffer */
+ if (image->type == KEXEC_TYPE_CRASH)
+ ret = walk_iomem_res("Crash kernel",
+ IORESOURCE_MEM | IORESOURCE_BUSY,
+ crashk_res.start, crashk_res.end, kbuf,
+ locate_mem_hole_callback);
+ else
+ ret = walk_system_ram_res(0, -1, kbuf,
+ locate_mem_hole_callback);
+ if (ret != 1) {
+ /* A suitable memory range could not be found for buffer */
+ return -EADDRNOTAVAIL;
+ }
+
+ /* Found a suitable memory range */
+ ksegment = &image->segment[image->nr_segments];
+ ksegment->kbuf = kbuf->buffer;
+ ksegment->bufsz = kbuf->bufsz;
+ ksegment->mem = kbuf->mem;
+ ksegment->memsz = kbuf->memsz;
+ image->nr_segments++;
+ *load_addr = ksegment->mem;
+ return 0;
+}
+
+/* Calculate and store the digest of segments */
+static int kexec_calculate_store_digests(struct kimage *image)
+{
+ struct crypto_shash *tfm;
+ struct shash_desc *desc;
+ int ret = 0, i, j, zero_buf_sz, sha_region_sz;
+ size_t desc_size, nullsz;
+ char *digest;
+ void *zero_buf;
+ struct kexec_sha_region *sha_regions;
+ struct purgatory_info *pi = &image->purgatory_info;
+
+ zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
+ zero_buf_sz = PAGE_SIZE;
+
+ tfm = crypto_alloc_shash("sha256", 0, 0);
+ if (IS_ERR(tfm)) {
+ ret = PTR_ERR(tfm);
+ goto out;
+ }
+
+ desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
+ desc = kzalloc(desc_size, GFP_KERNEL);
+ if (!desc) {
+ ret = -ENOMEM;
+ goto out_free_tfm;
+ }
+
+ sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
+ sha_regions = vzalloc(sha_region_sz);
+ if (!sha_regions)
+ goto out_free_desc;
+
+ desc->tfm = tfm;
+ desc->flags = 0;
+
+ ret = crypto_shash_init(desc);
+ if (ret < 0)
+ goto out_free_sha_regions;
+
+ digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
+ if (!digest) {
+ ret = -ENOMEM;
+ goto out_free_sha_regions;
+ }
+
+ for (j = i = 0; i < image->nr_segments; i++) {
+ struct kexec_segment *ksegment;
+
+ ksegment = &image->segment[i];
+ /*
+ * Skip purgatory as it will be modified once we put digest
+ * info in purgatory.
+ */
+ if (ksegment->kbuf == pi->purgatory_buf)
+ continue;
+
+ ret = crypto_shash_update(desc, ksegment->kbuf,
+ ksegment->bufsz);
+ if (ret)
+ break;
+
+ /*
+ * Assume rest of the buffer is filled with zero and
+ * update digest accordingly.
+ */
+ nullsz = ksegment->memsz - ksegment->bufsz;
+ while (nullsz) {
+ unsigned long bytes = nullsz;
+
+ if (bytes > zero_buf_sz)
+ bytes = zero_buf_sz;
+ ret = crypto_shash_update(desc, zero_buf, bytes);
+ if (ret)
+ break;
+ nullsz -= bytes;
+ }
+
+ if (ret)
+ break;
+
+ sha_regions[j].start = ksegment->mem;
+ sha_regions[j].len = ksegment->memsz;
+ j++;
+ }
+
+ if (!ret) {
+ ret = crypto_shash_final(desc, digest);
+ if (ret)
+ goto out_free_digest;
+ ret = kexec_purgatory_get_set_symbol(image, "sha_regions",
+ sha_regions, sha_region_sz, 0);
+ if (ret)
+ goto out_free_digest;
+
+ ret = kexec_purgatory_get_set_symbol(image, "sha256_digest",
+ digest, SHA256_DIGEST_SIZE, 0);
+ if (ret)
+ goto out_free_digest;
+ }
+
+out_free_digest:
+ kfree(digest);
+out_free_sha_regions:
+ vfree(sha_regions);
+out_free_desc:
+ kfree(desc);
+out_free_tfm:
+ kfree(tfm);
+out:
+ return ret;
+}
+
+/* Actually load purgatory. Lot of code taken from kexec-tools */
+static int __kexec_load_purgatory(struct kimage *image, unsigned long min,
+ unsigned long max, int top_down)
+{
+ struct purgatory_info *pi = &image->purgatory_info;
+ unsigned long align, buf_align, bss_align, buf_sz, bss_sz, bss_pad;
+ unsigned long memsz, entry, load_addr, curr_load_addr, bss_addr, offset;
+ unsigned char *buf_addr, *src;
+ int i, ret = 0, entry_sidx = -1;
+ const Elf_Shdr *sechdrs_c;
+ Elf_Shdr *sechdrs = NULL;
+ void *purgatory_buf = NULL;
+
+ /*
+ * sechdrs_c points to section headers in purgatory and are read
+ * only. No modifications allowed.
+ */
+ sechdrs_c = (void *)pi->ehdr + pi->ehdr->e_shoff;
+
+ /*
+ * We can not modify sechdrs_c[] and its fields. It is read only.
+ * Copy it over to a local copy where one can store some temporary
+ * data and free it at the end. We need to modify ->sh_addr and
+ * ->sh_offset fields to keep track of permanent and temporary
+ * locations of sections.
+ */
+ sechdrs = vzalloc(pi->ehdr->e_shnum * sizeof(Elf_Shdr));
+ if (!sechdrs)
+ return -ENOMEM;
+
+ memcpy(sechdrs, sechdrs_c, pi->ehdr->e_shnum * sizeof(Elf_Shdr));
+
+ /*
+ * We seem to have multiple copies of sections. First copy is which
+ * is embedded in kernel in read only section. Some of these sections
+ * will be copied to a temporary buffer and relocated. And these
+ * sections will finally be copied to their final destination at
+ * segment load time.
+ *
+ * Use ->sh_offset to reflect section address in memory. It will
+ * point to original read only copy if section is not allocatable.
+ * Otherwise it will point to temporary copy which will be relocated.
+ *
+ * Use ->sh_addr to contain final address of the section where it
+ * will go during execution time.
+ */
+ for (i = 0; i < pi->ehdr->e_shnum; i++) {
+ if (sechdrs[i].sh_type == SHT_NOBITS)
+ continue;
+
+ sechdrs[i].sh_offset = (unsigned long)pi->ehdr +
+ sechdrs[i].sh_offset;
+ }
+
+ /*
+ * Identify entry point section and make entry relative to section
+ * start.
+ */
+ entry = pi->ehdr->e_entry;
+ for (i = 0; i < pi->ehdr->e_shnum; i++) {
+ if (!(sechdrs[i].sh_flags & SHF_ALLOC))
+ continue;
+
+ if (!(sechdrs[i].sh_flags & SHF_EXECINSTR))
+ continue;
+
+ /* Make entry section relative */
+ if (sechdrs[i].sh_addr <= pi->ehdr->e_entry &&
+ ((sechdrs[i].sh_addr + sechdrs[i].sh_size) >
+ pi->ehdr->e_entry)) {
+ entry_sidx = i;
+ entry -= sechdrs[i].sh_addr;
+ break;
+ }
+ }
+
+ /* Determine how much memory is needed to load relocatable object. */
+ buf_align = 1;
+ bss_align = 1;
+ buf_sz = 0;
+ bss_sz = 0;
+
+ for (i = 0; i < pi->ehdr->e_shnum; i++) {
+ if (!(sechdrs[i].sh_flags & SHF_ALLOC))
+ continue;
+
+ align = sechdrs[i].sh_addralign;
+ if (sechdrs[i].sh_type != SHT_NOBITS) {
+ if (buf_align < align)
+ buf_align = align;
+ buf_sz = ALIGN(buf_sz, align);
+ buf_sz += sechdrs[i].sh_size;
+ } else {
+ /* bss section */
+ if (bss_align < align)
+ bss_align = align;
+ bss_sz = ALIGN(bss_sz, align);
+ bss_sz += sechdrs[i].sh_size;
+ }
+ }
+
+ /* Determine the bss padding required to align bss properly */
+ bss_pad = 0;
+ if (buf_sz & (bss_align - 1))
+ bss_pad = bss_align - (buf_sz & (bss_align - 1));
+
+ memsz = buf_sz + bss_pad + bss_sz;
+
+ /* Allocate buffer for purgatory */
+ purgatory_buf = vzalloc(buf_sz);
+ if (!purgatory_buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (buf_align < bss_align)
+ buf_align = bss_align;
+
+ /* Add buffer to segment list */
+ ret = kexec_add_buffer(image, purgatory_buf, buf_sz, memsz,
+ buf_align, min, max, top_down,
+ &pi->purgatory_load_addr);
+ if (ret)
+ goto out;
+
+ /* Load SHF_ALLOC sections */
+ buf_addr = purgatory_buf;
+ load_addr = curr_load_addr = pi->purgatory_load_addr;
+ bss_addr = load_addr + buf_sz + bss_pad;
+
+ for (i = 0; i < pi->ehdr->e_shnum; i++) {
+ if (!(sechdrs[i].sh_flags & SHF_ALLOC))
+ continue;
+
+ align = sechdrs[i].sh_addralign;
+ if (sechdrs[i].sh_type != SHT_NOBITS) {
+ curr_load_addr = ALIGN(curr_load_addr, align);
+ offset = curr_load_addr - load_addr;
+ /* We already modifed ->sh_offset to keep src addr */
+ src = (char *) sechdrs[i].sh_offset;
+ memcpy(buf_addr + offset, src, sechdrs[i].sh_size);
+
+ /* Store load address and source address of section */
+ sechdrs[i].sh_addr = curr_load_addr;
+
+ /*
+ * This section got copied to temporary buffer. Update
+ * ->sh_offset accordingly.
+ */
+ sechdrs[i].sh_offset = (unsigned long)(buf_addr + offset);
+
+ /* Advance to the next address */
+ curr_load_addr += sechdrs[i].sh_size;
+ } else {
+ bss_addr = ALIGN(bss_addr, align);
+ sechdrs[i].sh_addr = bss_addr;
+ bss_addr += sechdrs[i].sh_size;
+ }
+ }
+
+ /* Update entry point based on load address of text section */
+ if (entry_sidx >= 0)
+ entry += sechdrs[entry_sidx].sh_addr;
+
+ /* Make kernel jump to purgatory after shutdown */
+ image->start = entry;
+
+ /* Used later to get/set symbol values */
+ pi->sechdrs = sechdrs;
+
+ /*
+ * Used later to identify which section is purgatory and skip it
+ * from checksumming.
+ */
+ pi->purgatory_buf = purgatory_buf;
+ return ret;
+out:
+ vfree(sechdrs);
+ vfree(purgatory_buf);
+ return ret;
+}
+
+static int kexec_apply_relocations(struct kimage *image)
+{
+ int i, ret;
+ struct purgatory_info *pi = &image->purgatory_info;
+ Elf_Shdr *sechdrs = pi->sechdrs;
+
+ /* Apply relocations */
+ for (i = 0; i < pi->ehdr->e_shnum; i++) {
+ Elf_Shdr *section, *symtab;
+
+ if (sechdrs[i].sh_type != SHT_RELA &&
+ sechdrs[i].sh_type != SHT_REL)
+ continue;
+
+ /*
+ * For section of type SHT_RELA/SHT_REL,
+ * ->sh_link contains section header index of associated
+ * symbol table. And ->sh_info contains section header
+ * index of section to which relocations apply.
+ */
+ if (sechdrs[i].sh_info >= pi->ehdr->e_shnum ||
+ sechdrs[i].sh_link >= pi->ehdr->e_shnum)
+ return -ENOEXEC;
+
+ section = &sechdrs[sechdrs[i].sh_info];
+ symtab = &sechdrs[sechdrs[i].sh_link];
+
+ if (!(section->sh_flags & SHF_ALLOC))
+ continue;
+
+ /*
+ * symtab->sh_link contain section header index of associated
+ * string table.
+ */
+ if (symtab->sh_link >= pi->ehdr->e_shnum)
+ /* Invalid section number? */
+ continue;
+
+ /*
+ * Respective architecture needs to provide support for applying
+ * relocations of type SHT_RELA/SHT_REL.
+ */
+ if (sechdrs[i].sh_type == SHT_RELA)
+ ret = arch_kexec_apply_relocations_add(pi->ehdr,
+ sechdrs, i);
+ else if (sechdrs[i].sh_type == SHT_REL)
+ ret = arch_kexec_apply_relocations(pi->ehdr,
+ sechdrs, i);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+/* Load relocatable purgatory object and relocate it appropriately */
+int kexec_load_purgatory(struct kimage *image, unsigned long min,
+ unsigned long max, int top_down,
+ unsigned long *load_addr)
+{
+ struct purgatory_info *pi = &image->purgatory_info;
+ int ret;
+
+ if (kexec_purgatory_size <= 0)
+ return -EINVAL;
+
+ if (kexec_purgatory_size < sizeof(Elf_Ehdr))
+ return -ENOEXEC;
+
+ pi->ehdr = (Elf_Ehdr *)kexec_purgatory;
+
+ if (memcmp(pi->ehdr->e_ident, ELFMAG, SELFMAG) != 0
+ || pi->ehdr->e_type != ET_REL
+ || !elf_check_arch(pi->ehdr)
+ || pi->ehdr->e_shentsize != sizeof(Elf_Shdr))
+ return -ENOEXEC;
+
+ if (pi->ehdr->e_shoff >= kexec_purgatory_size
+ || (pi->ehdr->e_shnum * sizeof(Elf_Shdr) >
+ kexec_purgatory_size - pi->ehdr->e_shoff))
+ return -ENOEXEC;
+
+ ret = __kexec_load_purgatory(image, min, max, top_down);
+ if (ret)
+ return ret;
+
+ ret = kexec_apply_relocations(image);
+ if (ret)
+ goto out;
+
+ *load_addr = pi->purgatory_load_addr;
+ return 0;
+out:
+ vfree(pi->sechdrs);
+ vfree(pi->purgatory_buf);
+ return ret;
+}
+
+static Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
+ const char *name)
+{
+ Elf_Sym *syms;
+ Elf_Shdr *sechdrs;
+ Elf_Ehdr *ehdr;
+ int i, k;
+ const char *strtab;
+
+ if (!pi->sechdrs || !pi->ehdr)
+ return NULL;
+
+ sechdrs = pi->sechdrs;
+ ehdr = pi->ehdr;
+
+ for (i = 0; i < ehdr->e_shnum; i++) {
+ if (sechdrs[i].sh_type != SHT_SYMTAB)
+ continue;
+
+ if (sechdrs[i].sh_link >= ehdr->e_shnum)
+ /* Invalid strtab section number */
+ continue;
+ strtab = (char *)sechdrs[sechdrs[i].sh_link].sh_offset;
+ syms = (Elf_Sym *)sechdrs[i].sh_offset;
+
+ /* Go through symbols for a match */
+ for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
+ if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
+ continue;
+
+ if (strcmp(strtab + syms[k].st_name, name) != 0)
+ continue;
+
+ if (syms[k].st_shndx == SHN_UNDEF ||
+ syms[k].st_shndx >= ehdr->e_shnum) {
+ pr_debug("Symbol: %s has bad section index %d.\n",
+ name, syms[k].st_shndx);
+ return NULL;
+ }
+
+ /* Found the symbol we are looking for */
+ return &syms[k];
+ }
+ }
+
+ return NULL;
+}
+
+void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
+{
+ struct purgatory_info *pi = &image->purgatory_info;
+ Elf_Sym *sym;
+ Elf_Shdr *sechdr;
+
+ sym = kexec_purgatory_find_symbol(pi, name);
+ if (!sym)
+ return ERR_PTR(-EINVAL);
+
+ sechdr = &pi->sechdrs[sym->st_shndx];
+
+ /*
+ * Returns the address where symbol will finally be loaded after
+ * kexec_load_segment()
+ */
+ return (void *)(sechdr->sh_addr + sym->st_value);
+}
+
+/*
+ * Get or set value of a symbol. If "get_value" is true, symbol value is
+ * returned in buf otherwise symbol value is set based on value in buf.
+ */
+int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
+ void *buf, unsigned int size, bool get_value)
+{
+ Elf_Sym *sym;
+ Elf_Shdr *sechdrs;
+ struct purgatory_info *pi = &image->purgatory_info;
+ char *sym_buf;
+
+ sym = kexec_purgatory_find_symbol(pi, name);
+ if (!sym)
+ return -EINVAL;
+
+ if (sym->st_size != size) {
+ pr_err("symbol %s size mismatch: expected %lu actual %u\n",
+ name, (unsigned long)sym->st_size, size);
+ return -EINVAL;
+ }
+
+ sechdrs = pi->sechdrs;
+
+ if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
+ pr_err("symbol %s is in a bss section. Cannot %s\n", name,
+ get_value ? "get" : "set");
+ return -EINVAL;
+ }
+
+ sym_buf = (unsigned char *)sechdrs[sym->st_shndx].sh_offset +
+ sym->st_value;
+
+ if (get_value)
+ memcpy((void *)buf, sym_buf, size);
+ else
+ memcpy((void *)sym_buf, buf, size);
+
+ return 0;
+}
diff --git a/kernel/kexec_internal.h b/kernel/kexec_internal.h
new file mode 100644
index 0000000..e4392a6
--- /dev/null
+++ b/kernel/kexec_internal.h
@@ -0,0 +1,22 @@
+#ifndef LINUX_KEXEC_INTERNAL_H
+#define LINUX_KEXEC_INTERNAL_H
+
+#include <linux/kexec.h>
+
+struct kimage *do_kimage_alloc_init(void);
+int sanity_check_segment_list(struct kimage *image);
+void kimage_free_page_list(struct list_head *list);
+void kimage_free(struct kimage *image);
+int kimage_load_segment(struct kimage *image, struct kexec_segment *segment);
+void kimage_terminate(struct kimage *image);
+int kimage_is_destination_range(struct kimage *image,
+ unsigned long start, unsigned long end);
+
+extern struct mutex kexec_mutex;
+
+#ifdef CONFIG_KEXEC_FILE
+void kimage_file_post_load_cleanup(struct kimage *image);
+#else /* CONFIG_KEXEC_FILE */
+static inline void kimage_file_post_load_cleanup(struct kimage *image) { }
+#endif /* CONFIG_KEXEC_FILE */
+#endif /* LINUX_KEXEC_INTERNAL_H */
--
1.8.3.1
^ permalink raw reply related [flat|nested] 14+ messages in thread* [PATCH 2/3] [PATCH 2/3] kexec: split kexec_load syscall from kexec core code
2015-07-13 2:13 [PATCH 0/3] kexec: refactor CONFIG_KEXEC/CONFIG_KEXEC_FILE Kconfig dyoung
2015-07-13 2:13 ` [PATCH 1/3] [PATCH 1/3] kexec: split kexec_file syscall code to kexec_file.c dyoung
@ 2015-07-13 2:13 ` dyoung
2015-07-13 8:55 ` Geert Uytterhoeven
2015-07-13 2:13 ` [PATCH 3/3] [PATCH 3/3] kexec-x86-kdebug-h-drop-useless-macro dyoung
2015-07-15 9:16 ` [PATCH 0/3] kexec: refactor CONFIG_KEXEC/CONFIG_KEXEC_FILE Kconfig Dave Young
3 siblings, 1 reply; 14+ messages in thread
From: dyoung @ 2015-07-13 2:13 UTC (permalink / raw)
To: linux-kernel, kexec
Cc: dyoung, ebiederm, vgoyal, ptesarik, tytso, jwboyer, dhowells
[-- Attachment #1: 0002-kexec-split-kexec_load-syscall-from-kexec-core-code.patch --]
[-- Type: text/plain, Size: 103075 bytes --]
Now there's two kexec load syscall, one is kexec_load another is
kexec_file_load, kexec_file_load has been splited as kernel/kexec_file.c.
In this patch I split kexec_load syscall code to kernel/kexec.c.
And add a new kconfig option KEXEC_CORE, so we can disable kexec_load
and use kexec_file_load only, or vice verse.
The original requirement is from Tedso, he want kexec kernel signature being
checked with CONFIG_KEXEC_VERIFY_SIG enabled. But kexec-tools use kexec_load
syscall can bypass the checking.
Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel. KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.
Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig. Also updated general kernel code with
to kexec_load syscall.
Signed-off-by: Dave Young <dyoung@redhat.com>
---
arch/arm/Kconfig | 4 +
arch/ia64/Kconfig | 4 +
arch/m68k/Kconfig | 4 +
arch/mips/Kconfig | 4 +
arch/powerpc/Kconfig | 4 +
arch/sh/Kconfig | 4 +
arch/tile/Kconfig | 4 +
arch/x86/Kconfig | 6 +-
| 2 +-
arch/x86/include/asm/kdebug.h | 2 +-
arch/x86/kernel/Makefile | 4 +-
arch/x86/kernel/kvmclock.c | 4 +-
arch/x86/kernel/reboot.c | 4 +-
arch/x86/kernel/setup.c | 2 +-
arch/x86/kernel/vmlinux.lds.S | 2 +-
arch/x86/kvm/vmx.c | 8 +-
arch/x86/platform/efi/efi.c | 4 +-
arch/x86/platform/uv/uv_nmi.c | 6 +-
drivers/firmware/efi/Kconfig | 2 +-
drivers/pci/pci-driver.c | 2 +-
include/linux/kexec.h | 12 +-
init/initramfs.c | 4 +-
kernel/Makefile | 1 +
kernel/events/core.c | 2 +-
kernel/kexec.c | 1578 +---------------------------------------
kernel/kexec_core.c | 1594 +++++++++++++++++++++++++++++++++++++++++
kernel/ksysfs.c | 6 +-
kernel/printk/printk.c | 2 +-
kernel/reboot.c | 2 +-
kernel/sysctl.c | 2 +-
30 files changed, 1668 insertions(+), 1611 deletions(-)
create mode 100644 kernel/kexec_core.c
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 1c50210..20c48b3 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -2001,10 +2001,14 @@ config XIP_PHYS_ADDR
be linked for and stored to. This address is dependent on your
own flash usage.
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "Kexec system call (EXPERIMENTAL)"
depends on (!SMP || PM_SLEEP_SMP)
depends on !CPU_V7M
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 42a91a7..7db8fb7 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -515,9 +515,13 @@ config IA64_HP_AML_NFW
source "drivers/sn/Kconfig"
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
depends on !IA64_HP_SIM && (!SMP || HOTPLUG_CPU)
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 2dd8f63..875c518 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -92,9 +92,13 @@ config MMU_SUN3
bool
depends on MMU && !MMU_MOTOROLA && !MMU_COLDFIRE
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
depends on M68KCLASSIC
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 2a14585..0084fb6 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2594,8 +2594,12 @@ config SCHED_HRTICK
source "kernel/Kconfig.preempt"
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "Kexec system call"
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 5ef2711..68d6674 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -412,9 +412,13 @@ config PPC64_SUPPORTS_MEMORY_FAILURE
default "y" if PPC_POWERNV
select ARCH_SUPPORTS_MEMORY_FAILURE
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP))
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 50057fe..9edd1cc 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -599,9 +599,13 @@ menu "Kernel features"
source kernel/Kconfig.hz
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call (EXPERIMENTAL)"
depends on SUPERH32 && MMU
+ select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index 9def1f5..aa533a7 100644
--- a/arch/tile/Kconfig
+++ b/arch/tile/Kconfig
@@ -202,8 +202,12 @@ endif
source "kernel/Kconfig.hz"
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
+ select KEXEC_CORE
---help---
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 55bced1..290a912 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1716,8 +1716,12 @@ config SECCOMP
source kernel/Kconfig.hz
+config KEXEC_CORE
+ bool
+
config KEXEC
bool "kexec system call"
+ select KEXEC_CORE
---help---
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
@@ -1734,8 +1738,8 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
+ select KEXEC_CORE
select BUILD_BIN2C
- depends on KEXEC
depends on X86_64
depends on CRYPTO=y
depends on CRYPTO_SHA256=y
--git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 16ef025..2d6b309 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -414,7 +414,7 @@ xloadflags:
# define XLF23 0
#endif
-#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC)
+#if defined(CONFIG_X86_64) && defined(CONFIG_EFI) && defined(CONFIG_KEXEC_CORE)
# define XLF4 XLF_EFI_KEXEC
#else
# define XLF4 0
diff --git a/arch/x86/include/asm/kdebug.h b/arch/x86/include/asm/kdebug.h
index 32ce713..b130d59 100644
--- a/arch/x86/include/asm/kdebug.h
+++ b/arch/x86/include/asm/kdebug.h
@@ -29,7 +29,7 @@ extern void show_trace(struct task_struct *t, struct pt_regs *regs,
extern void __show_regs(struct pt_regs *regs, int all);
extern unsigned long oops_begin(void);
extern void oops_end(unsigned long, struct pt_regs *, int signr);
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
extern int in_crash_kexec;
#else
/* no crash dump is ever in progress if no crash kernel can be kexec'd */
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 0f15af4..d538d42 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -69,8 +69,8 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o
obj-$(CONFIG_FTRACE_SYSCALLS) += ftrace.o
obj-$(CONFIG_X86_TSC) += trace_clock.o
-obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o
-obj-$(CONFIG_KEXEC) += relocate_kernel_$(BITS).o crash.o
+obj-$(CONFIG_KEXEC_CORE) += machine_kexec_$(BITS).o
+obj-$(CONFIG_KEXEC_CORE) += relocate_kernel_$(BITS).o crash.o
obj-$(CONFIG_KEXEC_FILE) += kexec-bzimage64.o
obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o
obj-y += kprobes/
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index 49487b4..2c7aafa 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -200,7 +200,7 @@ static void kvm_setup_secondary_clock(void)
* kind of shutdown from our side, we unregister the clock by writting anything
* that does not have the 'enable' bit set in the msr
*/
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
static void kvm_crash_shutdown(struct pt_regs *regs)
{
native_write_msr(msr_kvm_system_time, 0, 0);
@@ -259,7 +259,7 @@ void __init kvmclock_init(void)
x86_platform.save_sched_clock_state = kvm_save_sched_clock_state;
x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state;
machine_ops.shutdown = kvm_shutdown;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
machine_ops.crash_shutdown = kvm_crash_shutdown;
#endif
kvm_get_preset_lpj();
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 86db4bc..02693dd 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -673,7 +673,7 @@ struct machine_ops machine_ops = {
.emergency_restart = native_machine_emergency_restart,
.restart = native_machine_restart,
.halt = native_machine_halt,
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
.crash_shutdown = native_machine_crash_shutdown,
#endif
};
@@ -703,7 +703,7 @@ void machine_halt(void)
machine_ops.halt();
}
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
void machine_crash_shutdown(struct pt_regs *regs)
{
machine_ops.crash_shutdown(regs);
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 80f874b..1c0faa7 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -498,7 +498,7 @@ static void __init memblock_x86_reserve_range_setup_data(void)
* --------- Crashkernel reservation ------------------------------
*/
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* Keep the crash kernel below this limit. On 32 bits earlier kernels
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 00bf300..74e4bf1 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -364,7 +364,7 @@ INIT_PER_CPU(irq_stack_union);
#endif /* CONFIG_X86_32 */
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
#include <asm/kexec.h>
. = ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e856dd5..32e61e9 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1264,7 +1264,7 @@ static void vmcs_load(struct vmcs *vmcs)
vmcs, phys_addr);
}
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* This bitmap is used to indicate whether the vmclear
* operation is enabled on all cpus. All disabled by
@@ -1302,7 +1302,7 @@ static void crash_vmclear_local_loaded_vmcss(void)
#else
static inline void crash_enable_local_vmclear(int cpu) { }
static inline void crash_disable_local_vmclear(int cpu) { }
-#endif /* CONFIG_KEXEC */
+#endif /* CONFIG_KEXEC_CORE */
static void __loaded_vmcs_clear(void *arg)
{
@@ -10430,7 +10430,7 @@ static int __init vmx_init(void)
if (r)
return r;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
rcu_assign_pointer(crash_vmclear_loaded_vmcss,
crash_vmclear_local_loaded_vmcss);
#endif
@@ -10440,7 +10440,7 @@ static int __init vmx_init(void)
static void __exit vmx_exit(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL);
synchronize_rcu();
#endif
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index cfba30f..f1e5419 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -650,7 +650,7 @@ static void __init get_systab_virt_addr(efi_memory_desc_t *md)
static void __init save_runtime_map(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
efi_memory_desc_t *md;
void *tmp, *p, *q = NULL;
int count = 0;
@@ -748,7 +748,7 @@ static void * __init efi_map_regions(int *count, int *pg_shift)
static void __init kexec_enter_virtual_mode(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
efi_memory_desc_t *md;
void *p;
diff --git a/arch/x86/platform/uv/uv_nmi.c b/arch/x86/platform/uv/uv_nmi.c
index 020c101..5c9f63f 100644
--- a/arch/x86/platform/uv/uv_nmi.c
+++ b/arch/x86/platform/uv/uv_nmi.c
@@ -492,7 +492,7 @@ static void uv_nmi_touch_watchdogs(void)
touch_nmi_watchdog();
}
-#if defined(CONFIG_KEXEC)
+#if defined(CONFIG_KEXEC_CORE)
static atomic_t uv_nmi_kexec_failed;
static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
{
@@ -519,13 +519,13 @@ static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
uv_nmi_sync_exit(0);
}
-#else /* !CONFIG_KEXEC */
+#else /* !CONFIG_KEXEC_CORE */
static inline void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
{
if (master)
pr_err("UV: NMI kdump: KEXEC not supported in this kernel\n");
}
-#endif /* !CONFIG_KEXEC */
+#endif /* !CONFIG_KEXEC_CORE */
#ifdef CONFIG_KGDB
#ifdef CONFIG_KGDB_KDB
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 54071c1..84533e0 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -43,7 +43,7 @@ config EFI_VARS_PSTORE_DEFAULT_DISABLE
config EFI_RUNTIME_MAP
bool "Export efi runtime maps to sysfs"
- depends on X86 && EFI && KEXEC
+ depends on X86 && EFI && KEXEC_CORE
default y
help
Export efi runtime memory maps to /sys/firmware/efi/runtime-map.
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 3cb2210..2bf9532 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -453,7 +453,7 @@ static void pci_device_shutdown(struct device *dev)
pci_msi_shutdown(pci_dev);
pci_msix_shutdown(pci_dev);
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* If this is a kexec reboot, turn off Bus Master bit on the
* device to tell it to not continue to do DMA. Don't touch
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index e804306..79c1bca 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -16,7 +16,7 @@
#include <uapi/linux/kexec.h>
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
#include <linux/list.h>
#include <linux/linkage.h>
#include <linux/compat.h>
@@ -318,12 +318,18 @@ int crash_shrink_memory(unsigned long new_size);
size_t crash_get_memory_size(void);
void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
-#else /* !CONFIG_KEXEC */
+#ifdef CONFIG_KEXEC
+int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
+ unsigned long nr_segments,
+ struct kexec_segment __user *segments,
+ unsigned long flags);
+#endif
+#else /* !CONFIG_KEXEC_CORE */
struct pt_regs;
struct task_struct;
static inline void crash_kexec(struct pt_regs *regs) { }
static inline int kexec_should_crash(struct task_struct *p) { return 0; }
-#endif /* CONFIG_KEXEC */
+#endif /* CONFIG_KEXEC_CORE */
#endif /* !defined(__ASSEBMLY__) */
diff --git a/init/initramfs.c b/init/initramfs.c
index ad1bd77..b32ad7d 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -526,14 +526,14 @@ extern unsigned long __initramfs_size;
static void __init free_initrd(void)
{
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
unsigned long crashk_end = (unsigned long)__va(crashk_res.end);
#endif
if (do_retain_initrd)
goto skip;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* If the initrd region is overlapped with crashkernel reserved region,
* free only memory that is not part of crashkernel region.
diff --git a/kernel/Makefile b/kernel/Makefile
index f178fe4..af9708d 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_MODULE_SIG) += module_signing.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
+obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
diff --git a/kernel/events/core.c b/kernel/events/core.c
index d3dae34..a9a6bc1 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8872,7 +8872,7 @@ static void perf_event_init_cpu(int cpu)
mutex_unlock(&swhash->hlist_mutex);
}
-#if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC
+#if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE
static void __perf_event_exit_context(void *__info)
{
struct remove_event re = { .detach_group = true };
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 641b2db..6c48d1c 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1,938 +1,20 @@
/*
- * kexec.c - kexec system call
+ * kexec.c - kexec_load system call
* Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com>
*
* This source code is licensed under the GNU General Public License,
* Version 2. See the file COPYING for more details.
*/
-#define pr_fmt(fmt) "kexec: " fmt
-
#include <linux/capability.h>
#include <linux/mm.h>
#include <linux/file.h>
-#include <linux/slab.h>
-#include <linux/fs.h>
#include <linux/kexec.h>
#include <linux/mutex.h>
#include <linux/list.h>
-#include <linux/highmem.h>
#include <linux/syscalls.h>
-#include <linux/reboot.h>
-#include <linux/ioport.h>
-#include <linux/hardirq.h>
-#include <linux/elf.h>
-#include <linux/elfcore.h>
-#include <linux/utsname.h>
-#include <linux/numa.h>
-#include <linux/suspend.h>
-#include <linux/device.h>
-#include <linux/freezer.h>
-#include <linux/pm.h>
-#include <linux/cpu.h>
-#include <linux/console.h>
-#include <linux/swap.h>
-#include <linux/syscore_ops.h>
-#include <linux/compiler.h>
-#include <linux/hugetlb.h>
-
-#include <asm/page.h>
-#include <asm/uaccess.h>
-#include <asm/io.h>
-#include <asm/sections.h>
-
-#include <crypto/hash.h>
-#include <crypto/sha.h>
#include "kexec_internal.h"
-DEFINE_MUTEX(kexec_mutex);
-
-/* Per cpu memory for storing cpu states in case of system crash. */
-note_buf_t __percpu *crash_notes;
-
-/* vmcoreinfo stuff */
-static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
-u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
-size_t vmcoreinfo_size;
-size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);
-
-/* Flag to indicate we are going to kexec a new kernel */
-bool kexec_in_progress = false;
-
-
-/* Location of the reserved area for the crash kernel */
-struct resource crashk_res = {
- .name = "Crash kernel",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_BUSY | IORESOURCE_MEM
-};
-struct resource crashk_low_res = {
- .name = "Crash kernel",
- .start = 0,
- .end = 0,
- .flags = IORESOURCE_BUSY | IORESOURCE_MEM
-};
-
-int kexec_should_crash(struct task_struct *p)
-{
- /*
- * If crash_kexec_post_notifiers is enabled, don't run
- * crash_kexec() here yet, which must be run after panic
- * notifiers in panic().
- */
- if (crash_kexec_post_notifiers)
- return 0;
- /*
- * There are 4 panic() calls in do_exit() path, each of which
- * corresponds to each of these 4 conditions.
- */
- if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
- return 1;
- return 0;
-}
-
-/*
- * When kexec transitions to the new kernel there is a one-to-one
- * mapping between physical and virtual addresses. On processors
- * where you can disable the MMU this is trivial, and easy. For
- * others it is still a simple predictable page table to setup.
- *
- * In that environment kexec copies the new kernel to its final
- * resting place. This means I can only support memory whose
- * physical address can fit in an unsigned long. In particular
- * addresses where (pfn << PAGE_SHIFT) > ULONG_MAX cannot be handled.
- * If the assembly stub has more restrictive requirements
- * KEXEC_SOURCE_MEMORY_LIMIT and KEXEC_DEST_MEMORY_LIMIT can be
- * defined more restrictively in <asm/kexec.h>.
- *
- * The code for the transition from the current kernel to the
- * the new kernel is placed in the control_code_buffer, whose size
- * is given by KEXEC_CONTROL_PAGE_SIZE. In the best case only a single
- * page of memory is necessary, but some architectures require more.
- * Because this memory must be identity mapped in the transition from
- * virtual to physical addresses it must live in the range
- * 0 - TASK_SIZE, as only the user space mappings are arbitrarily
- * modifiable.
- *
- * The assembly stub in the control code buffer is passed a linked list
- * of descriptor pages detailing the source pages of the new kernel,
- * and the destination addresses of those source pages. As this data
- * structure is not used in the context of the current OS, it must
- * be self-contained.
- *
- * The code has been made to work with highmem pages and will use a
- * destination page in its final resting place (if it happens
- * to allocate it). The end product of this is that most of the
- * physical address space, and most of RAM can be used.
- *
- * Future directions include:
- * - allocating a page table with the control code buffer identity
- * mapped, to simplify machine_kexec and make kexec_on_panic more
- * reliable.
- */
-
-/*
- * KIMAGE_NO_DEST is an impossible destination address..., for
- * allocating pages whose destination address we do not care about.
- */
-#define KIMAGE_NO_DEST (-1UL)
-
-static struct page *kimage_alloc_page(struct kimage *image,
- gfp_t gfp_mask,
- unsigned long dest);
-
-static int copy_user_segment_list(struct kimage *image,
- unsigned long nr_segments,
- struct kexec_segment __user *segments)
-{
- int ret;
- size_t segment_bytes;
-
- /* Read in the segments */
- image->nr_segments = nr_segments;
- segment_bytes = nr_segments * sizeof(*segments);
- ret = copy_from_user(image->segment, segments, segment_bytes);
- if (ret)
- ret = -EFAULT;
-
- return ret;
-}
-
-int sanity_check_segment_list(struct kimage *image)
-{
- int result, i;
- unsigned long nr_segments = image->nr_segments;
-
- /*
- * Verify we have good destination addresses. The caller is
- * responsible for making certain we don't attempt to load
- * the new image into invalid or reserved areas of RAM. This
- * just verifies it is an address we can use.
- *
- * Since the kernel does everything in page size chunks ensure
- * the destination addresses are page aligned. Too many
- * special cases crop of when we don't do this. The most
- * insidious is getting overlapping destination addresses
- * simply because addresses are changed to page size
- * granularity.
- */
- result = -EADDRNOTAVAIL;
- for (i = 0; i < nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK))
- return result;
- if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT)
- return result;
- }
-
- /* Verify our destination addresses do not overlap.
- * If we alloed overlapping destination addresses
- * through very weird things can happen with no
- * easy explanation as one segment stops on another.
- */
- result = -EINVAL;
- for (i = 0; i < nr_segments; i++) {
- unsigned long mstart, mend;
- unsigned long j;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- for (j = 0; j < i; j++) {
- unsigned long pstart, pend;
- pstart = image->segment[j].mem;
- pend = pstart + image->segment[j].memsz;
- /* Do the segments overlap ? */
- if ((mend > pstart) && (mstart < pend))
- return result;
- }
- }
-
- /* Ensure our buffer sizes are strictly less than
- * our memory sizes. This should always be the case,
- * and it is easier to check up front than to be surprised
- * later on.
- */
- result = -EINVAL;
- for (i = 0; i < nr_segments; i++) {
- if (image->segment[i].bufsz > image->segment[i].memsz)
- return result;
- }
-
- /*
- * Verify we have good destination addresses. Normally
- * the caller is responsible for making certain we don't
- * attempt to load the new image into invalid or reserved
- * areas of RAM. But crash kernels are preloaded into a
- * reserved area of ram. We must ensure the addresses
- * are in the reserved area otherwise preloading the
- * kernel could corrupt things.
- */
-
- if (image->type == KEXEC_TYPE_CRASH) {
- result = -EADDRNOTAVAIL;
- for (i = 0; i < nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz - 1;
- /* Ensure we are within the crash kernel limits */
- if ((mstart < crashk_res.start) ||
- (mend > crashk_res.end))
- return result;
- }
- }
-
- return 0;
-}
-
-struct kimage *do_kimage_alloc_init(void)
-{
- struct kimage *image;
-
- /* Allocate a controlling structure */
- image = kzalloc(sizeof(*image), GFP_KERNEL);
- if (!image)
- return NULL;
-
- image->head = 0;
- image->entry = &image->head;
- image->last_entry = &image->head;
- image->control_page = ~0; /* By default this does not apply */
- image->type = KEXEC_TYPE_DEFAULT;
-
- /* Initialize the list of control pages */
- INIT_LIST_HEAD(&image->control_pages);
-
- /* Initialize the list of destination pages */
- INIT_LIST_HEAD(&image->dest_pages);
-
- /* Initialize the list of unusable pages */
- INIT_LIST_HEAD(&image->unusable_pages);
-
- return image;
-}
-
-static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
- unsigned long nr_segments,
- struct kexec_segment __user *segments,
- unsigned long flags)
-{
- int ret;
- struct kimage *image;
- bool kexec_on_panic = flags & KEXEC_ON_CRASH;
-
- if (kexec_on_panic) {
- /* Verify we have a valid entry point */
- if ((entry < crashk_res.start) || (entry > crashk_res.end))
- return -EADDRNOTAVAIL;
- }
-
- /* Allocate and initialize a controlling structure */
- image = do_kimage_alloc_init();
- if (!image)
- return -ENOMEM;
-
- image->start = entry;
-
- ret = copy_user_segment_list(image, nr_segments, segments);
- if (ret)
- goto out_free_image;
-
- ret = sanity_check_segment_list(image);
- if (ret)
- goto out_free_image;
-
- /* Enable the special crash kernel control page allocation policy. */
- if (kexec_on_panic) {
- image->control_page = crashk_res.start;
- image->type = KEXEC_TYPE_CRASH;
- }
-
- /*
- * Find a location for the control code buffer, and add it
- * the vector of segments so that it's pages will also be
- * counted as destination pages.
- */
- ret = -ENOMEM;
- image->control_code_page = kimage_alloc_control_pages(image,
- get_order(KEXEC_CONTROL_PAGE_SIZE));
- if (!image->control_code_page) {
- pr_err("Could not allocate control_code_buffer\n");
- goto out_free_image;
- }
-
- if (!kexec_on_panic) {
- image->swap_page = kimage_alloc_control_pages(image, 0);
- if (!image->swap_page) {
- pr_err("Could not allocate swap buffer\n");
- goto out_free_control_pages;
- }
- }
-
- *rimage = image;
- return 0;
-out_free_control_pages:
- kimage_free_page_list(&image->control_pages);
-out_free_image:
- kfree(image);
- return ret;
-}
-
-int kimage_is_destination_range(struct kimage *image,
- unsigned long start,
- unsigned long end)
-{
- unsigned long i;
-
- for (i = 0; i < image->nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz;
- if ((end > mstart) && (start < mend))
- return 1;
- }
-
- return 0;
-}
-
-static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order)
-{
- struct page *pages;
-
- pages = alloc_pages(gfp_mask, order);
- if (pages) {
- unsigned int count, i;
- pages->mapping = NULL;
- set_page_private(pages, order);
- count = 1 << order;
- for (i = 0; i < count; i++)
- SetPageReserved(pages + i);
- }
-
- return pages;
-}
-
-static void kimage_free_pages(struct page *page)
-{
- unsigned int order, count, i;
-
- order = page_private(page);
- count = 1 << order;
- for (i = 0; i < count; i++)
- ClearPageReserved(page + i);
- __free_pages(page, order);
-}
-
-void kimage_free_page_list(struct list_head *list)
-{
- struct list_head *pos, *next;
-
- list_for_each_safe(pos, next, list) {
- struct page *page;
-
- page = list_entry(pos, struct page, lru);
- list_del(&page->lru);
- kimage_free_pages(page);
- }
-}
-
-static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
- unsigned int order)
-{
- /* Control pages are special, they are the intermediaries
- * that are needed while we copy the rest of the pages
- * to their final resting place. As such they must
- * not conflict with either the destination addresses
- * or memory the kernel is already using.
- *
- * The only case where we really need more than one of
- * these are for architectures where we cannot disable
- * the MMU and must instead generate an identity mapped
- * page table for all of the memory.
- *
- * At worst this runs in O(N) of the image size.
- */
- struct list_head extra_pages;
- struct page *pages;
- unsigned int count;
-
- count = 1 << order;
- INIT_LIST_HEAD(&extra_pages);
-
- /* Loop while I can allocate a page and the page allocated
- * is a destination page.
- */
- do {
- unsigned long pfn, epfn, addr, eaddr;
-
- pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
- if (!pages)
- break;
- pfn = page_to_pfn(pages);
- epfn = pfn + count;
- addr = pfn << PAGE_SHIFT;
- eaddr = epfn << PAGE_SHIFT;
- if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
- kimage_is_destination_range(image, addr, eaddr)) {
- list_add(&pages->lru, &extra_pages);
- pages = NULL;
- }
- } while (!pages);
-
- if (pages) {
- /* Remember the allocated page... */
- list_add(&pages->lru, &image->control_pages);
-
- /* Because the page is already in it's destination
- * location we will never allocate another page at
- * that address. Therefore kimage_alloc_pages
- * will not return it (again) and we don't need
- * to give it an entry in image->segment[].
- */
- }
- /* Deal with the destination pages I have inadvertently allocated.
- *
- * Ideally I would convert multi-page allocations into single
- * page allocations, and add everything to image->dest_pages.
- *
- * For now it is simpler to just free the pages.
- */
- kimage_free_page_list(&extra_pages);
-
- return pages;
-}
-
-static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
- unsigned int order)
-{
- /* Control pages are special, they are the intermediaries
- * that are needed while we copy the rest of the pages
- * to their final resting place. As such they must
- * not conflict with either the destination addresses
- * or memory the kernel is already using.
- *
- * Control pages are also the only pags we must allocate
- * when loading a crash kernel. All of the other pages
- * are specified by the segments and we just memcpy
- * into them directly.
- *
- * The only case where we really need more than one of
- * these are for architectures where we cannot disable
- * the MMU and must instead generate an identity mapped
- * page table for all of the memory.
- *
- * Given the low demand this implements a very simple
- * allocator that finds the first hole of the appropriate
- * size in the reserved memory region, and allocates all
- * of the memory up to and including the hole.
- */
- unsigned long hole_start, hole_end, size;
- struct page *pages;
-
- pages = NULL;
- size = (1 << order) << PAGE_SHIFT;
- hole_start = (image->control_page + (size - 1)) & ~(size - 1);
- hole_end = hole_start + size - 1;
- while (hole_end <= crashk_res.end) {
- unsigned long i;
-
- if (hole_end > KEXEC_CRASH_CONTROL_MEMORY_LIMIT)
- break;
- /* See if I overlap any of the segments */
- for (i = 0; i < image->nr_segments; i++) {
- unsigned long mstart, mend;
-
- mstart = image->segment[i].mem;
- mend = mstart + image->segment[i].memsz - 1;
- if ((hole_end >= mstart) && (hole_start <= mend)) {
- /* Advance the hole to the end of the segment */
- hole_start = (mend + (size - 1)) & ~(size - 1);
- hole_end = hole_start + size - 1;
- break;
- }
- }
- /* If I don't overlap any segments I have found my hole! */
- if (i == image->nr_segments) {
- pages = pfn_to_page(hole_start >> PAGE_SHIFT);
- break;
- }
- }
- if (pages)
- image->control_page = hole_end;
-
- return pages;
-}
-
-
-struct page *kimage_alloc_control_pages(struct kimage *image,
- unsigned int order)
-{
- struct page *pages = NULL;
-
- switch (image->type) {
- case KEXEC_TYPE_DEFAULT:
- pages = kimage_alloc_normal_control_pages(image, order);
- break;
- case KEXEC_TYPE_CRASH:
- pages = kimage_alloc_crash_control_pages(image, order);
- break;
- }
-
- return pages;
-}
-
-static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
-{
- if (*image->entry != 0)
- image->entry++;
-
- if (image->entry == image->last_entry) {
- kimage_entry_t *ind_page;
- struct page *page;
-
- page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST);
- if (!page)
- return -ENOMEM;
-
- ind_page = page_address(page);
- *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
- image->entry = ind_page;
- image->last_entry = ind_page +
- ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
- }
- *image->entry = entry;
- image->entry++;
- *image->entry = 0;
-
- return 0;
-}
-
-static int kimage_set_destination(struct kimage *image,
- unsigned long destination)
-{
- int result;
-
- destination &= PAGE_MASK;
- result = kimage_add_entry(image, destination | IND_DESTINATION);
-
- return result;
-}
-
-
-static int kimage_add_page(struct kimage *image, unsigned long page)
-{
- int result;
-
- page &= PAGE_MASK;
- result = kimage_add_entry(image, page | IND_SOURCE);
-
- return result;
-}
-
-
-static void kimage_free_extra_pages(struct kimage *image)
-{
- /* Walk through and free any extra destination pages I may have */
- kimage_free_page_list(&image->dest_pages);
-
- /* Walk through and free any unusable pages I have cached */
- kimage_free_page_list(&image->unusable_pages);
-
-}
-void kimage_terminate(struct kimage *image)
-{
- if (*image->entry != 0)
- image->entry++;
-
- *image->entry = IND_DONE;
-}
-
-#define for_each_kimage_entry(image, ptr, entry) \
- for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \
- ptr = (entry & IND_INDIRECTION) ? \
- phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
-
-static void kimage_free_entry(kimage_entry_t entry)
-{
- struct page *page;
-
- page = pfn_to_page(entry >> PAGE_SHIFT);
- kimage_free_pages(page);
-}
-
-void kimage_free(struct kimage *image)
-{
- kimage_entry_t *ptr, entry;
- kimage_entry_t ind = 0;
-
- if (!image)
- return;
-
- kimage_free_extra_pages(image);
- for_each_kimage_entry(image, ptr, entry) {
- if (entry & IND_INDIRECTION) {
- /* Free the previous indirection page */
- if (ind & IND_INDIRECTION)
- kimage_free_entry(ind);
- /* Save this indirection page until we are
- * done with it.
- */
- ind = entry;
- } else if (entry & IND_SOURCE)
- kimage_free_entry(entry);
- }
- /* Free the final indirection page */
- if (ind & IND_INDIRECTION)
- kimage_free_entry(ind);
-
- /* Handle any machine specific cleanup */
- machine_kexec_cleanup(image);
-
- /* Free the kexec control pages... */
- kimage_free_page_list(&image->control_pages);
-
- /*
- * Free up any temporary buffers allocated. This might hit if
- * error occurred much later after buffer allocation.
- */
- if (image->file_mode)
- kimage_file_post_load_cleanup(image);
-
- kfree(image);
-}
-
-static kimage_entry_t *kimage_dst_used(struct kimage *image,
- unsigned long page)
-{
- kimage_entry_t *ptr, entry;
- unsigned long destination = 0;
-
- for_each_kimage_entry(image, ptr, entry) {
- if (entry & IND_DESTINATION)
- destination = entry & PAGE_MASK;
- else if (entry & IND_SOURCE) {
- if (page == destination)
- return ptr;
- destination += PAGE_SIZE;
- }
- }
-
- return NULL;
-}
-
-static struct page *kimage_alloc_page(struct kimage *image,
- gfp_t gfp_mask,
- unsigned long destination)
-{
- /*
- * Here we implement safeguards to ensure that a source page
- * is not copied to its destination page before the data on
- * the destination page is no longer useful.
- *
- * To do this we maintain the invariant that a source page is
- * either its own destination page, or it is not a
- * destination page at all.
- *
- * That is slightly stronger than required, but the proof
- * that no problems will not occur is trivial, and the
- * implementation is simply to verify.
- *
- * When allocating all pages normally this algorithm will run
- * in O(N) time, but in the worst case it will run in O(N^2)
- * time. If the runtime is a problem the data structures can
- * be fixed.
- */
- struct page *page;
- unsigned long addr;
-
- /*
- * Walk through the list of destination pages, and see if I
- * have a match.
- */
- list_for_each_entry(page, &image->dest_pages, lru) {
- addr = page_to_pfn(page) << PAGE_SHIFT;
- if (addr == destination) {
- list_del(&page->lru);
- return page;
- }
- }
- page = NULL;
- while (1) {
- kimage_entry_t *old;
-
- /* Allocate a page, if we run out of memory give up */
- page = kimage_alloc_pages(gfp_mask, 0);
- if (!page)
- return NULL;
- /* If the page cannot be used file it away */
- if (page_to_pfn(page) >
- (KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) {
- list_add(&page->lru, &image->unusable_pages);
- continue;
- }
- addr = page_to_pfn(page) << PAGE_SHIFT;
-
- /* If it is the destination page we want use it */
- if (addr == destination)
- break;
-
- /* If the page is not a destination page use it */
- if (!kimage_is_destination_range(image, addr,
- addr + PAGE_SIZE))
- break;
-
- /*
- * I know that the page is someones destination page.
- * See if there is already a source page for this
- * destination page. And if so swap the source pages.
- */
- old = kimage_dst_used(image, addr);
- if (old) {
- /* If so move it */
- unsigned long old_addr;
- struct page *old_page;
-
- old_addr = *old & PAGE_MASK;
- old_page = pfn_to_page(old_addr >> PAGE_SHIFT);
- copy_highpage(page, old_page);
- *old = addr | (*old & ~PAGE_MASK);
-
- /* The old page I have found cannot be a
- * destination page, so return it if it's
- * gfp_flags honor the ones passed in.
- */
- if (!(gfp_mask & __GFP_HIGHMEM) &&
- PageHighMem(old_page)) {
- kimage_free_pages(old_page);
- continue;
- }
- addr = old_addr;
- page = old_page;
- break;
- } else {
- /* Place the page on the destination list I
- * will use it later.
- */
- list_add(&page->lru, &image->dest_pages);
- }
- }
-
- return page;
-}
-
-static int kimage_load_normal_segment(struct kimage *image,
- struct kexec_segment *segment)
-{
- unsigned long maddr;
- size_t ubytes, mbytes;
- int result;
- unsigned char __user *buf = NULL;
- unsigned char *kbuf = NULL;
-
- result = 0;
- if (image->file_mode)
- kbuf = segment->kbuf;
- else
- buf = segment->buf;
- ubytes = segment->bufsz;
- mbytes = segment->memsz;
- maddr = segment->mem;
-
- result = kimage_set_destination(image, maddr);
- if (result < 0)
- goto out;
-
- while (mbytes) {
- struct page *page;
- char *ptr;
- size_t uchunk, mchunk;
-
- page = kimage_alloc_page(image, GFP_HIGHUSER, maddr);
- if (!page) {
- result = -ENOMEM;
- goto out;
- }
- result = kimage_add_page(image, page_to_pfn(page)
- << PAGE_SHIFT);
- if (result < 0)
- goto out;
-
- ptr = kmap(page);
- /* Start with a clear page */
- clear_page(ptr);
- ptr += maddr & ~PAGE_MASK;
- mchunk = min_t(size_t, mbytes,
- PAGE_SIZE - (maddr & ~PAGE_MASK));
- uchunk = min(ubytes, mchunk);
-
- /* For file based kexec, source pages are in kernel memory */
- if (image->file_mode)
- memcpy(ptr, kbuf, uchunk);
- else
- result = copy_from_user(ptr, buf, uchunk);
- kunmap(page);
- if (result) {
- result = -EFAULT;
- goto out;
- }
- ubytes -= uchunk;
- maddr += mchunk;
- if (image->file_mode)
- kbuf += mchunk;
- else
- buf += mchunk;
- mbytes -= mchunk;
- }
-out:
- return result;
-}
-
-static int kimage_load_crash_segment(struct kimage *image,
- struct kexec_segment *segment)
-{
- /* For crash dumps kernels we simply copy the data from
- * user space to it's destination.
- * We do things a page at a time for the sake of kmap.
- */
- unsigned long maddr;
- size_t ubytes, mbytes;
- int result;
- unsigned char __user *buf = NULL;
- unsigned char *kbuf = NULL;
-
- result = 0;
- if (image->file_mode)
- kbuf = segment->kbuf;
- else
- buf = segment->buf;
- ubytes = segment->bufsz;
- mbytes = segment->memsz;
- maddr = segment->mem;
- while (mbytes) {
- struct page *page;
- char *ptr;
- size_t uchunk, mchunk;
-
- page = pfn_to_page(maddr >> PAGE_SHIFT);
- if (!page) {
- result = -ENOMEM;
- goto out;
- }
- ptr = kmap(page);
- ptr += maddr & ~PAGE_MASK;
- mchunk = min_t(size_t, mbytes,
- PAGE_SIZE - (maddr & ~PAGE_MASK));
- uchunk = min(ubytes, mchunk);
- if (mchunk > uchunk) {
- /* Zero the trailing part of the page */
- memset(ptr + uchunk, 0, mchunk - uchunk);
- }
-
- /* For file based kexec, source pages are in kernel memory */
- if (image->file_mode)
- memcpy(ptr, kbuf, uchunk);
- else
- result = copy_from_user(ptr, buf, uchunk);
- kexec_flush_icache_page(page);
- kunmap(page);
- if (result) {
- result = -EFAULT;
- goto out;
- }
- ubytes -= uchunk;
- maddr += mchunk;
- if (image->file_mode)
- kbuf += mchunk;
- else
- buf += mchunk;
- mbytes -= mchunk;
- }
-out:
- return result;
-}
-
-int kimage_load_segment(struct kimage *image,
- struct kexec_segment *segment)
-{
- int result = -ENOMEM;
-
- switch (image->type) {
- case KEXEC_TYPE_DEFAULT:
- result = kimage_load_normal_segment(image, segment);
- break;
- case KEXEC_TYPE_CRASH:
- result = kimage_load_crash_segment(image, segment);
- break;
- }
-
- return result;
-}
-
/*
* Exec Kernel system call: for obvious reasons only root may call it.
*
@@ -953,9 +35,6 @@ int kimage_load_segment(struct kimage *image,
* kexec does not sync, or unmount filesystems so if you need
* that to happen you need to do that yourself.
*/
-struct kimage *kexec_image;
-struct kimage *kexec_crash_image;
-int kexec_load_disabled;
SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
struct kexec_segment __user *, segments, unsigned long, flags)
@@ -1050,18 +129,6 @@ out:
return result;
}
-/*
- * Add and remove page tables for crashkernel memory
- *
- * Provide an empty default implementation here -- architecture
- * code may override this
- */
-void __weak crash_map_reserved_pages(void)
-{}
-
-void __weak crash_unmap_reserved_pages(void)
-{}
-
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
compat_ulong_t, nr_segments,
@@ -1100,646 +167,3 @@ COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
return sys_kexec_load(entry, nr_segments, ksegments, flags);
}
#endif
-
-void crash_kexec(struct pt_regs *regs)
-{
- /* Take the kexec_mutex here to prevent sys_kexec_load
- * running on one cpu from replacing the crash kernel
- * we are using after a panic on a different cpu.
- *
- * If the crash kernel was not located in a fixed area
- * of memory the xchg(&kexec_crash_image) would be
- * sufficient. But since I reuse the memory...
- */
- if (mutex_trylock(&kexec_mutex)) {
- if (kexec_crash_image) {
- struct pt_regs fixed_regs;
-
- crash_setup_regs(&fixed_regs, regs);
- crash_save_vmcoreinfo();
- machine_crash_shutdown(&fixed_regs);
- machine_kexec(kexec_crash_image);
- }
- mutex_unlock(&kexec_mutex);
- }
-}
-
-size_t crash_get_memory_size(void)
-{
- size_t size = 0;
- mutex_lock(&kexec_mutex);
- if (crashk_res.end != crashk_res.start)
- size = resource_size(&crashk_res);
- mutex_unlock(&kexec_mutex);
- return size;
-}
-
-void __weak crash_free_reserved_phys_range(unsigned long begin,
- unsigned long end)
-{
- unsigned long addr;
-
- for (addr = begin; addr < end; addr += PAGE_SIZE)
- free_reserved_page(pfn_to_page(addr >> PAGE_SHIFT));
-}
-
-int crash_shrink_memory(unsigned long new_size)
-{
- int ret = 0;
- unsigned long start, end;
- unsigned long old_size;
- struct resource *ram_res;
-
- mutex_lock(&kexec_mutex);
-
- if (kexec_crash_image) {
- ret = -ENOENT;
- goto unlock;
- }
- start = crashk_res.start;
- end = crashk_res.end;
- old_size = (end == 0) ? 0 : end - start + 1;
- if (new_size >= old_size) {
- ret = (new_size == old_size) ? 0 : -EINVAL;
- goto unlock;
- }
-
- ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
- if (!ram_res) {
- ret = -ENOMEM;
- goto unlock;
- }
-
- start = roundup(start, KEXEC_CRASH_MEM_ALIGN);
- end = roundup(start + new_size, KEXEC_CRASH_MEM_ALIGN);
-
- crash_map_reserved_pages();
- crash_free_reserved_phys_range(end, crashk_res.end);
-
- if ((start == end) && (crashk_res.parent != NULL))
- release_resource(&crashk_res);
-
- ram_res->start = end;
- ram_res->end = crashk_res.end;
- ram_res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
- ram_res->name = "System RAM";
-
- crashk_res.end = end - 1;
-
- insert_resource(&iomem_resource, ram_res);
- crash_unmap_reserved_pages();
-
-unlock:
- mutex_unlock(&kexec_mutex);
- return ret;
-}
-
-static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
- size_t data_len)
-{
- struct elf_note note;
-
- note.n_namesz = strlen(name) + 1;
- note.n_descsz = data_len;
- note.n_type = type;
- memcpy(buf, ¬e, sizeof(note));
- buf += (sizeof(note) + 3)/4;
- memcpy(buf, name, note.n_namesz);
- buf += (note.n_namesz + 3)/4;
- memcpy(buf, data, note.n_descsz);
- buf += (note.n_descsz + 3)/4;
-
- return buf;
-}
-
-static void final_note(u32 *buf)
-{
- struct elf_note note;
-
- note.n_namesz = 0;
- note.n_descsz = 0;
- note.n_type = 0;
- memcpy(buf, ¬e, sizeof(note));
-}
-
-void crash_save_cpu(struct pt_regs *regs, int cpu)
-{
- struct elf_prstatus prstatus;
- u32 *buf;
-
- if ((cpu < 0) || (cpu >= nr_cpu_ids))
- return;
-
- /* Using ELF notes here is opportunistic.
- * I need a well defined structure format
- * for the data I pass, and I need tags
- * on the data to indicate what information I have
- * squirrelled away. ELF notes happen to provide
- * all of that, so there is no need to invent something new.
- */
- buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
- if (!buf)
- return;
- memset(&prstatus, 0, sizeof(prstatus));
- prstatus.pr_pid = current->pid;
- elf_core_copy_kernel_regs(&prstatus.pr_reg, regs);
- buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
- &prstatus, sizeof(prstatus));
- final_note(buf);
-}
-
-static int __init crash_notes_memory_init(void)
-{
- /* Allocate memory for saving cpu registers. */
- crash_notes = alloc_percpu(note_buf_t);
- if (!crash_notes) {
- pr_warn("Kexec: Memory allocation for saving cpu register states failed\n");
- return -ENOMEM;
- }
- return 0;
-}
-subsys_initcall(crash_notes_memory_init);
-
-
-/*
- * parsing the "crashkernel" commandline
- *
- * this code is intended to be called from architecture specific code
- */
-
-
-/*
- * This function parses command lines in the format
- *
- * crashkernel=ramsize-range:size[,...][@offset]
- *
- * The function returns 0 on success and -EINVAL on failure.
- */
-static int __init parse_crashkernel_mem(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- char *cur = cmdline, *tmp;
-
- /* for each entry of the comma-separated list */
- do {
- unsigned long long start, end = ULLONG_MAX, size;
-
- /* get the start of the range */
- start = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("crashkernel: Memory value expected\n");
- return -EINVAL;
- }
- cur = tmp;
- if (*cur != '-') {
- pr_warn("crashkernel: '-' expected\n");
- return -EINVAL;
- }
- cur++;
-
- /* if no ':' is here, than we read the end */
- if (*cur != ':') {
- end = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("crashkernel: Memory value expected\n");
- return -EINVAL;
- }
- cur = tmp;
- if (end <= start) {
- pr_warn("crashkernel: end <= start\n");
- return -EINVAL;
- }
- }
-
- if (*cur != ':') {
- pr_warn("crashkernel: ':' expected\n");
- return -EINVAL;
- }
- cur++;
-
- size = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("Memory value expected\n");
- return -EINVAL;
- }
- cur = tmp;
- if (size >= system_ram) {
- pr_warn("crashkernel: invalid size\n");
- return -EINVAL;
- }
-
- /* match ? */
- if (system_ram >= start && system_ram < end) {
- *crash_size = size;
- break;
- }
- } while (*cur++ == ',');
-
- if (*crash_size > 0) {
- while (*cur && *cur != ' ' && *cur != '@')
- cur++;
- if (*cur == '@') {
- cur++;
- *crash_base = memparse(cur, &tmp);
- if (cur == tmp) {
- pr_warn("Memory value expected after '@'\n");
- return -EINVAL;
- }
- }
- }
-
- return 0;
-}
-
-/*
- * That function parses "simple" (old) crashkernel command lines like
- *
- * crashkernel=size[@offset]
- *
- * It returns 0 on success and -EINVAL on failure.
- */
-static int __init parse_crashkernel_simple(char *cmdline,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- char *cur = cmdline;
-
- *crash_size = memparse(cmdline, &cur);
- if (cmdline == cur) {
- pr_warn("crashkernel: memory value expected\n");
- return -EINVAL;
- }
-
- if (*cur == '@')
- *crash_base = memparse(cur+1, &cur);
- else if (*cur != ' ' && *cur != '\0') {
- pr_warn("crashkernel: unrecognized char\n");
- return -EINVAL;
- }
-
- return 0;
-}
-
-#define SUFFIX_HIGH 0
-#define SUFFIX_LOW 1
-#define SUFFIX_NULL 2
-static __initdata char *suffix_tbl[] = {
- [SUFFIX_HIGH] = ",high",
- [SUFFIX_LOW] = ",low",
- [SUFFIX_NULL] = NULL,
-};
-
-/*
- * That function parses "suffix" crashkernel command lines like
- *
- * crashkernel=size,[high|low]
- *
- * It returns 0 on success and -EINVAL on failure.
- */
-static int __init parse_crashkernel_suffix(char *cmdline,
- unsigned long long *crash_size,
- const char *suffix)
-{
- char *cur = cmdline;
-
- *crash_size = memparse(cmdline, &cur);
- if (cmdline == cur) {
- pr_warn("crashkernel: memory value expected\n");
- return -EINVAL;
- }
-
- /* check with suffix */
- if (strncmp(cur, suffix, strlen(suffix))) {
- pr_warn("crashkernel: unrecognized char\n");
- return -EINVAL;
- }
- cur += strlen(suffix);
- if (*cur != ' ' && *cur != '\0') {
- pr_warn("crashkernel: unrecognized char\n");
- return -EINVAL;
- }
-
- return 0;
-}
-
-static __init char *get_last_crashkernel(char *cmdline,
- const char *name,
- const char *suffix)
-{
- char *p = cmdline, *ck_cmdline = NULL;
-
- /* find crashkernel and use the last one if there are more */
- p = strstr(p, name);
- while (p) {
- char *end_p = strchr(p, ' ');
- char *q;
-
- if (!end_p)
- end_p = p + strlen(p);
-
- if (!suffix) {
- int i;
-
- /* skip the one with any known suffix */
- for (i = 0; suffix_tbl[i]; i++) {
- q = end_p - strlen(suffix_tbl[i]);
- if (!strncmp(q, suffix_tbl[i],
- strlen(suffix_tbl[i])))
- goto next;
- }
- ck_cmdline = p;
- } else {
- q = end_p - strlen(suffix);
- if (!strncmp(q, suffix, strlen(suffix)))
- ck_cmdline = p;
- }
-next:
- p = strstr(p+1, name);
- }
-
- if (!ck_cmdline)
- return NULL;
-
- return ck_cmdline;
-}
-
-static int __init __parse_crashkernel(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base,
- const char *name,
- const char *suffix)
-{
- char *first_colon, *first_space;
- char *ck_cmdline;
-
- BUG_ON(!crash_size || !crash_base);
- *crash_size = 0;
- *crash_base = 0;
-
- ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
-
- if (!ck_cmdline)
- return -EINVAL;
-
- ck_cmdline += strlen(name);
-
- if (suffix)
- return parse_crashkernel_suffix(ck_cmdline, crash_size,
- suffix);
- /*
- * if the commandline contains a ':', then that's the extended
- * syntax -- if not, it must be the classic syntax
- */
- first_colon = strchr(ck_cmdline, ':');
- first_space = strchr(ck_cmdline, ' ');
- if (first_colon && (!first_space || first_colon < first_space))
- return parse_crashkernel_mem(ck_cmdline, system_ram,
- crash_size, crash_base);
-
- return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base);
-}
-
-/*
- * That function is the entry point for command line parsing and should be
- * called from the arch-specific code.
- */
-int __init parse_crashkernel(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
- "crashkernel=", NULL);
-}
-
-int __init parse_crashkernel_high(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
- "crashkernel=", suffix_tbl[SUFFIX_HIGH]);
-}
-
-int __init parse_crashkernel_low(char *cmdline,
- unsigned long long system_ram,
- unsigned long long *crash_size,
- unsigned long long *crash_base)
-{
- return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
- "crashkernel=", suffix_tbl[SUFFIX_LOW]);
-}
-
-static void update_vmcoreinfo_note(void)
-{
- u32 *buf = vmcoreinfo_note;
-
- if (!vmcoreinfo_size)
- return;
- buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
- vmcoreinfo_size);
- final_note(buf);
-}
-
-void crash_save_vmcoreinfo(void)
-{
- vmcoreinfo_append_str("CRASHTIME=%ld\n", get_seconds());
- update_vmcoreinfo_note();
-}
-
-void vmcoreinfo_append_str(const char *fmt, ...)
-{
- va_list args;
- char buf[0x50];
- size_t r;
-
- va_start(args, fmt);
- r = vscnprintf(buf, sizeof(buf), fmt, args);
- va_end(args);
-
- r = min(r, vmcoreinfo_max_size - vmcoreinfo_size);
-
- memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
-
- vmcoreinfo_size += r;
-}
-
-/*
- * provide an empty default implementation here -- architecture
- * code may override this
- */
-void __weak arch_crash_save_vmcoreinfo(void)
-{}
-
-unsigned long __weak paddr_vmcoreinfo_note(void)
-{
- return __pa((unsigned long)(char *)&vmcoreinfo_note);
-}
-
-static int __init crash_save_vmcoreinfo_init(void)
-{
- VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
- VMCOREINFO_PAGESIZE(PAGE_SIZE);
-
- VMCOREINFO_SYMBOL(init_uts_ns);
- VMCOREINFO_SYMBOL(node_online_map);
-#ifdef CONFIG_MMU
- VMCOREINFO_SYMBOL(swapper_pg_dir);
-#endif
- VMCOREINFO_SYMBOL(_stext);
- VMCOREINFO_SYMBOL(vmap_area_list);
-
-#ifndef CONFIG_NEED_MULTIPLE_NODES
- VMCOREINFO_SYMBOL(mem_map);
- VMCOREINFO_SYMBOL(contig_page_data);
-#endif
-#ifdef CONFIG_SPARSEMEM
- VMCOREINFO_SYMBOL(mem_section);
- VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
- VMCOREINFO_STRUCT_SIZE(mem_section);
- VMCOREINFO_OFFSET(mem_section, section_mem_map);
-#endif
- VMCOREINFO_STRUCT_SIZE(page);
- VMCOREINFO_STRUCT_SIZE(pglist_data);
- VMCOREINFO_STRUCT_SIZE(zone);
- VMCOREINFO_STRUCT_SIZE(free_area);
- VMCOREINFO_STRUCT_SIZE(list_head);
- VMCOREINFO_SIZE(nodemask_t);
- VMCOREINFO_OFFSET(page, flags);
- VMCOREINFO_OFFSET(page, _count);
- VMCOREINFO_OFFSET(page, mapping);
- VMCOREINFO_OFFSET(page, lru);
- VMCOREINFO_OFFSET(page, _mapcount);
- VMCOREINFO_OFFSET(page, private);
- VMCOREINFO_OFFSET(pglist_data, node_zones);
- VMCOREINFO_OFFSET(pglist_data, nr_zones);
-#ifdef CONFIG_FLAT_NODE_MEM_MAP
- VMCOREINFO_OFFSET(pglist_data, node_mem_map);
-#endif
- VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
- VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
- VMCOREINFO_OFFSET(pglist_data, node_id);
- VMCOREINFO_OFFSET(zone, free_area);
- VMCOREINFO_OFFSET(zone, vm_stat);
- VMCOREINFO_OFFSET(zone, spanned_pages);
- VMCOREINFO_OFFSET(free_area, free_list);
- VMCOREINFO_OFFSET(list_head, next);
- VMCOREINFO_OFFSET(list_head, prev);
- VMCOREINFO_OFFSET(vmap_area, va_start);
- VMCOREINFO_OFFSET(vmap_area, list);
- VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);
- log_buf_kexec_setup();
- VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
- VMCOREINFO_NUMBER(NR_FREE_PAGES);
- VMCOREINFO_NUMBER(PG_lru);
- VMCOREINFO_NUMBER(PG_private);
- VMCOREINFO_NUMBER(PG_swapcache);
- VMCOREINFO_NUMBER(PG_slab);
-#ifdef CONFIG_MEMORY_FAILURE
- VMCOREINFO_NUMBER(PG_hwpoison);
-#endif
- VMCOREINFO_NUMBER(PG_head_mask);
- VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
-#ifdef CONFIG_HUGETLBFS
- VMCOREINFO_SYMBOL(free_huge_page);
-#endif
-
- arch_crash_save_vmcoreinfo();
- update_vmcoreinfo_note();
-
- return 0;
-}
-
-subsys_initcall(crash_save_vmcoreinfo_init);
-
-/*
- * Move into place and start executing a preloaded standalone
- * executable. If nothing was preloaded return an error.
- */
-int kernel_kexec(void)
-{
- int error = 0;
-
- if (!mutex_trylock(&kexec_mutex))
- return -EBUSY;
- if (!kexec_image) {
- error = -EINVAL;
- goto Unlock;
- }
-
-#ifdef CONFIG_KEXEC_JUMP
- if (kexec_image->preserve_context) {
- lock_system_sleep();
- pm_prepare_console();
- error = freeze_processes();
- if (error) {
- error = -EBUSY;
- goto Restore_console;
- }
- suspend_console();
- error = dpm_suspend_start(PMSG_FREEZE);
- if (error)
- goto Resume_console;
- /* At this point, dpm_suspend_start() has been called,
- * but *not* dpm_suspend_end(). We *must* call
- * dpm_suspend_end() now. Otherwise, drivers for
- * some devices (e.g. interrupt controllers) become
- * desynchronized with the actual state of the
- * hardware at resume time, and evil weirdness ensues.
- */
- error = dpm_suspend_end(PMSG_FREEZE);
- if (error)
- goto Resume_devices;
- error = disable_nonboot_cpus();
- if (error)
- goto Enable_cpus;
- local_irq_disable();
- error = syscore_suspend();
- if (error)
- goto Enable_irqs;
- } else
-#endif
- {
- kexec_in_progress = true;
- kernel_restart_prepare(NULL);
- migrate_to_reboot_cpu();
-
- /*
- * migrate_to_reboot_cpu() disables CPU hotplug assuming that
- * no further code needs to use CPU hotplug (which is true in
- * the reboot case). However, the kexec path depends on using
- * CPU hotplug again; so re-enable it here.
- */
- cpu_hotplug_enable();
- pr_emerg("Starting new kernel\n");
- machine_shutdown();
- }
-
- machine_kexec(kexec_image);
-
-#ifdef CONFIG_KEXEC_JUMP
- if (kexec_image->preserve_context) {
- syscore_resume();
- Enable_irqs:
- local_irq_enable();
- Enable_cpus:
- enable_nonboot_cpus();
- dpm_resume_start(PMSG_RESTORE);
- Resume_devices:
- dpm_resume_end(PMSG_RESTORE);
- Resume_console:
- resume_console();
- thaw_processes();
- Restore_console:
- pm_restore_console();
- unlock_system_sleep();
- }
-#endif
-
- Unlock:
- mutex_unlock(&kexec_mutex);
- return error;
-}
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
new file mode 100644
index 0000000..8d4c047
--- /dev/null
+++ b/kernel/kexec_core.c
@@ -0,0 +1,1594 @@
+/*
+ * kexec.c - kexec system call core code.
+ * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#define pr_fmt(fmt) "kexec: " fmt
+
+#include <linux/capability.h>
+#include <linux/mm.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/kexec.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/highmem.h>
+#include <linux/syscalls.h>
+#include <linux/reboot.h>
+#include <linux/ioport.h>
+#include <linux/hardirq.h>
+#include <linux/elf.h>
+#include <linux/elfcore.h>
+#include <linux/utsname.h>
+#include <linux/numa.h>
+#include <linux/suspend.h>
+#include <linux/device.h>
+#include <linux/freezer.h>
+#include <linux/pm.h>
+#include <linux/cpu.h>
+#include <linux/console.h>
+#include <linux/vmalloc.h>
+#include <linux/swap.h>
+#include <linux/syscore_ops.h>
+#include <linux/compiler.h>
+#include <linux/hugetlb.h>
+
+#include <asm/page.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/sections.h>
+
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include "kexec_internal.h"
+
+DEFINE_MUTEX(kexec_mutex);
+
+/* Per cpu memory for storing cpu states in case of system crash. */
+note_buf_t __percpu *crash_notes;
+
+/* vmcoreinfo stuff */
+static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
+u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
+size_t vmcoreinfo_size;
+size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);
+
+/* Flag to indicate we are going to kexec a new kernel */
+bool kexec_in_progress = false;
+
+
+/* Location of the reserved area for the crash kernel */
+struct resource crashk_res = {
+ .name = "Crash kernel",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_MEM
+};
+struct resource crashk_low_res = {
+ .name = "Crash kernel",
+ .start = 0,
+ .end = 0,
+ .flags = IORESOURCE_BUSY | IORESOURCE_MEM
+};
+
+int kexec_should_crash(struct task_struct *p)
+{
+ /*
+ * If crash_kexec_post_notifiers is enabled, don't run
+ * crash_kexec() here yet, which must be run after panic
+ * notifiers in panic().
+ */
+ if (crash_kexec_post_notifiers)
+ return 0;
+ /*
+ * There are 4 panic() calls in do_exit() path, each of which
+ * corresponds to each of these 4 conditions.
+ */
+ if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
+ return 1;
+ return 0;
+}
+
+/*
+ * When kexec transitions to the new kernel there is a one-to-one
+ * mapping between physical and virtual addresses. On processors
+ * where you can disable the MMU this is trivial, and easy. For
+ * others it is still a simple predictable page table to setup.
+ *
+ * In that environment kexec copies the new kernel to its final
+ * resting place. This means I can only support memory whose
+ * physical address can fit in an unsigned long. In particular
+ * addresses where (pfn << PAGE_SHIFT) > ULONG_MAX cannot be handled.
+ * If the assembly stub has more restrictive requirements
+ * KEXEC_SOURCE_MEMORY_LIMIT and KEXEC_DEST_MEMORY_LIMIT can be
+ * defined more restrictively in <asm/kexec.h>.
+ *
+ * The code for the transition from the current kernel to the
+ * the new kernel is placed in the control_code_buffer, whose size
+ * is given by KEXEC_CONTROL_PAGE_SIZE. In the best case only a single
+ * page of memory is necessary, but some architectures require more.
+ * Because this memory must be identity mapped in the transition from
+ * virtual to physical addresses it must live in the range
+ * 0 - TASK_SIZE, as only the user space mappings are arbitrarily
+ * modifiable.
+ *
+ * The assembly stub in the control code buffer is passed a linked list
+ * of descriptor pages detailing the source pages of the new kernel,
+ * and the destination addresses of those source pages. As this data
+ * structure is not used in the context of the current OS, it must
+ * be self-contained.
+ *
+ * The code has been made to work with highmem pages and will use a
+ * destination page in its final resting place (if it happens
+ * to allocate it). The end product of this is that most of the
+ * physical address space, and most of RAM can be used.
+ *
+ * Future directions include:
+ * - allocating a page table with the control code buffer identity
+ * mapped, to simplify machine_kexec and make kexec_on_panic more
+ * reliable.
+ */
+
+/*
+ * KIMAGE_NO_DEST is an impossible destination address..., for
+ * allocating pages whose destination address we do not care about.
+ */
+#define KIMAGE_NO_DEST (-1UL)
+
+static struct page *kimage_alloc_page(struct kimage *image,
+ gfp_t gfp_mask,
+ unsigned long dest);
+
+static int copy_user_segment_list(struct kimage *image,
+ unsigned long nr_segments,
+ struct kexec_segment __user *segments)
+{
+ int ret;
+ size_t segment_bytes;
+
+ /* Read in the segments */
+ image->nr_segments = nr_segments;
+ segment_bytes = nr_segments * sizeof(*segments);
+ ret = copy_from_user(image->segment, segments, segment_bytes);
+ if (ret)
+ ret = -EFAULT;
+
+ return ret;
+}
+
+int sanity_check_segment_list(struct kimage *image)
+{
+ int result, i;
+ unsigned long nr_segments = image->nr_segments;
+
+ /*
+ * Verify we have good destination addresses. The caller is
+ * responsible for making certain we don't attempt to load
+ * the new image into invalid or reserved areas of RAM. This
+ * just verifies it is an address we can use.
+ *
+ * Since the kernel does everything in page size chunks ensure
+ * the destination addresses are page aligned. Too many
+ * special cases crop of when we don't do this. The most
+ * insidious is getting overlapping destination addresses
+ * simply because addresses are changed to page size
+ * granularity.
+ */
+ result = -EADDRNOTAVAIL;
+ for (i = 0; i < nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz;
+ if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK))
+ return result;
+ if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT)
+ return result;
+ }
+
+ /* Verify our destination addresses do not overlap.
+ * If we alloed overlapping destination addresses
+ * through very weird things can happen with no
+ * easy explanation as one segment stops on another.
+ */
+ result = -EINVAL;
+ for (i = 0; i < nr_segments; i++) {
+ unsigned long mstart, mend;
+ unsigned long j;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz;
+ for (j = 0; j < i; j++) {
+ unsigned long pstart, pend;
+ pstart = image->segment[j].mem;
+ pend = pstart + image->segment[j].memsz;
+ /* Do the segments overlap ? */
+ if ((mend > pstart) && (mstart < pend))
+ return result;
+ }
+ }
+
+ /* Ensure our buffer sizes are strictly less than
+ * our memory sizes. This should always be the case,
+ * and it is easier to check up front than to be surprised
+ * later on.
+ */
+ result = -EINVAL;
+ for (i = 0; i < nr_segments; i++) {
+ if (image->segment[i].bufsz > image->segment[i].memsz)
+ return result;
+ }
+
+ /*
+ * Verify we have good destination addresses. Normally
+ * the caller is responsible for making certain we don't
+ * attempt to load the new image into invalid or reserved
+ * areas of RAM. But crash kernels are preloaded into a
+ * reserved area of ram. We must ensure the addresses
+ * are in the reserved area otherwise preloading the
+ * kernel could corrupt things.
+ */
+
+ if (image->type == KEXEC_TYPE_CRASH) {
+ result = -EADDRNOTAVAIL;
+ for (i = 0; i < nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz - 1;
+ /* Ensure we are within the crash kernel limits */
+ if ((mstart < crashk_res.start) ||
+ (mend > crashk_res.end))
+ return result;
+ }
+ }
+
+ return 0;
+}
+
+struct kimage *do_kimage_alloc_init(void)
+{
+ struct kimage *image;
+
+ /* Allocate a controlling structure */
+ image = kzalloc(sizeof(*image), GFP_KERNEL);
+ if (!image)
+ return NULL;
+
+ image->head = 0;
+ image->entry = &image->head;
+ image->last_entry = &image->head;
+ image->control_page = ~0; /* By default this does not apply */
+ image->type = KEXEC_TYPE_DEFAULT;
+
+ /* Initialize the list of control pages */
+ INIT_LIST_HEAD(&image->control_pages);
+
+ /* Initialize the list of destination pages */
+ INIT_LIST_HEAD(&image->dest_pages);
+
+ /* Initialize the list of unusable pages */
+ INIT_LIST_HEAD(&image->unusable_pages);
+
+ return image;
+}
+
+int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
+ unsigned long nr_segments,
+ struct kexec_segment __user *segments,
+ unsigned long flags)
+{
+ int ret;
+ struct kimage *image;
+ bool kexec_on_panic = flags & KEXEC_ON_CRASH;
+
+ if (kexec_on_panic) {
+ /* Verify we have a valid entry point */
+ if ((entry < crashk_res.start) || (entry > crashk_res.end))
+ return -EADDRNOTAVAIL;
+ }
+
+ /* Allocate and initialize a controlling structure */
+ image = do_kimage_alloc_init();
+ if (!image)
+ return -ENOMEM;
+
+ image->start = entry;
+
+ ret = copy_user_segment_list(image, nr_segments, segments);
+ if (ret)
+ goto out_free_image;
+
+ ret = sanity_check_segment_list(image);
+ if (ret)
+ goto out_free_image;
+
+ /* Enable the special crash kernel control page allocation policy. */
+ if (kexec_on_panic) {
+ image->control_page = crashk_res.start;
+ image->type = KEXEC_TYPE_CRASH;
+ }
+
+ /*
+ * Find a location for the control code buffer, and add it
+ * the vector of segments so that it's pages will also be
+ * counted as destination pages.
+ */
+ ret = -ENOMEM;
+ image->control_code_page = kimage_alloc_control_pages(image,
+ get_order(KEXEC_CONTROL_PAGE_SIZE));
+ if (!image->control_code_page) {
+ pr_err("Could not allocate control_code_buffer\n");
+ goto out_free_image;
+ }
+
+ if (!kexec_on_panic) {
+ image->swap_page = kimage_alloc_control_pages(image, 0);
+ if (!image->swap_page) {
+ pr_err("Could not allocate swap buffer\n");
+ goto out_free_control_pages;
+ }
+ }
+
+ *rimage = image;
+ return 0;
+out_free_control_pages:
+ kimage_free_page_list(&image->control_pages);
+out_free_image:
+ kfree(image);
+ return ret;
+}
+
+int kimage_is_destination_range(struct kimage *image,
+ unsigned long start,
+ unsigned long end)
+{
+ unsigned long i;
+
+ for (i = 0; i < image->nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz;
+ if ((end > mstart) && (start < mend))
+ return 1;
+ }
+
+ return 0;
+}
+
+static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order)
+{
+ struct page *pages;
+
+ pages = alloc_pages(gfp_mask, order);
+ if (pages) {
+ unsigned int count, i;
+ pages->mapping = NULL;
+ set_page_private(pages, order);
+ count = 1 << order;
+ for (i = 0; i < count; i++)
+ SetPageReserved(pages + i);
+ }
+
+ return pages;
+}
+
+static void kimage_free_pages(struct page *page)
+{
+ unsigned int order, count, i;
+
+ order = page_private(page);
+ count = 1 << order;
+ for (i = 0; i < count; i++)
+ ClearPageReserved(page + i);
+ __free_pages(page, order);
+}
+
+void kimage_free_page_list(struct list_head *list)
+{
+ struct list_head *pos, *next;
+
+ list_for_each_safe(pos, next, list) {
+ struct page *page;
+
+ page = list_entry(pos, struct page, lru);
+ list_del(&page->lru);
+ kimage_free_pages(page);
+ }
+}
+
+static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
+ unsigned int order)
+{
+ /* Control pages are special, they are the intermediaries
+ * that are needed while we copy the rest of the pages
+ * to their final resting place. As such they must
+ * not conflict with either the destination addresses
+ * or memory the kernel is already using.
+ *
+ * The only case where we really need more than one of
+ * these are for architectures where we cannot disable
+ * the MMU and must instead generate an identity mapped
+ * page table for all of the memory.
+ *
+ * At worst this runs in O(N) of the image size.
+ */
+ struct list_head extra_pages;
+ struct page *pages;
+ unsigned int count;
+
+ count = 1 << order;
+ INIT_LIST_HEAD(&extra_pages);
+
+ /* Loop while I can allocate a page and the page allocated
+ * is a destination page.
+ */
+ do {
+ unsigned long pfn, epfn, addr, eaddr;
+
+ pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
+ if (!pages)
+ break;
+ pfn = page_to_pfn(pages);
+ epfn = pfn + count;
+ addr = pfn << PAGE_SHIFT;
+ eaddr = epfn << PAGE_SHIFT;
+ if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
+ kimage_is_destination_range(image, addr, eaddr)) {
+ list_add(&pages->lru, &extra_pages);
+ pages = NULL;
+ }
+ } while (!pages);
+
+ if (pages) {
+ /* Remember the allocated page... */
+ list_add(&pages->lru, &image->control_pages);
+
+ /* Because the page is already in it's destination
+ * location we will never allocate another page at
+ * that address. Therefore kimage_alloc_pages
+ * will not return it (again) and we don't need
+ * to give it an entry in image->segment[].
+ */
+ }
+ /* Deal with the destination pages I have inadvertently allocated.
+ *
+ * Ideally I would convert multi-page allocations into single
+ * page allocations, and add everything to image->dest_pages.
+ *
+ * For now it is simpler to just free the pages.
+ */
+ kimage_free_page_list(&extra_pages);
+
+ return pages;
+}
+
+static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
+ unsigned int order)
+{
+ /* Control pages are special, they are the intermediaries
+ * that are needed while we copy the rest of the pages
+ * to their final resting place. As such they must
+ * not conflict with either the destination addresses
+ * or memory the kernel is already using.
+ *
+ * Control pages are also the only pags we must allocate
+ * when loading a crash kernel. All of the other pages
+ * are specified by the segments and we just memcpy
+ * into them directly.
+ *
+ * The only case where we really need more than one of
+ * these are for architectures where we cannot disable
+ * the MMU and must instead generate an identity mapped
+ * page table for all of the memory.
+ *
+ * Given the low demand this implements a very simple
+ * allocator that finds the first hole of the appropriate
+ * size in the reserved memory region, and allocates all
+ * of the memory up to and including the hole.
+ */
+ unsigned long hole_start, hole_end, size;
+ struct page *pages;
+
+ pages = NULL;
+ size = (1 << order) << PAGE_SHIFT;
+ hole_start = (image->control_page + (size - 1)) & ~(size - 1);
+ hole_end = hole_start + size - 1;
+ while (hole_end <= crashk_res.end) {
+ unsigned long i;
+
+ if (hole_end > KEXEC_CRASH_CONTROL_MEMORY_LIMIT)
+ break;
+ /* See if I overlap any of the segments */
+ for (i = 0; i < image->nr_segments; i++) {
+ unsigned long mstart, mend;
+
+ mstart = image->segment[i].mem;
+ mend = mstart + image->segment[i].memsz - 1;
+ if ((hole_end >= mstart) && (hole_start <= mend)) {
+ /* Advance the hole to the end of the segment */
+ hole_start = (mend + (size - 1)) & ~(size - 1);
+ hole_end = hole_start + size - 1;
+ break;
+ }
+ }
+ /* If I don't overlap any segments I have found my hole! */
+ if (i == image->nr_segments) {
+ pages = pfn_to_page(hole_start >> PAGE_SHIFT);
+ break;
+ }
+ }
+ if (pages)
+ image->control_page = hole_end;
+
+ return pages;
+}
+
+
+struct page *kimage_alloc_control_pages(struct kimage *image,
+ unsigned int order)
+{
+ struct page *pages = NULL;
+
+ switch (image->type) {
+ case KEXEC_TYPE_DEFAULT:
+ pages = kimage_alloc_normal_control_pages(image, order);
+ break;
+ case KEXEC_TYPE_CRASH:
+ pages = kimage_alloc_crash_control_pages(image, order);
+ break;
+ }
+
+ return pages;
+}
+
+static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
+{
+ if (*image->entry != 0)
+ image->entry++;
+
+ if (image->entry == image->last_entry) {
+ kimage_entry_t *ind_page;
+ struct page *page;
+
+ page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST);
+ if (!page)
+ return -ENOMEM;
+
+ ind_page = page_address(page);
+ *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
+ image->entry = ind_page;
+ image->last_entry = ind_page +
+ ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
+ }
+ *image->entry = entry;
+ image->entry++;
+ *image->entry = 0;
+
+ return 0;
+}
+
+static int kimage_set_destination(struct kimage *image,
+ unsigned long destination)
+{
+ int result;
+
+ destination &= PAGE_MASK;
+ result = kimage_add_entry(image, destination | IND_DESTINATION);
+
+ return result;
+}
+
+
+static int kimage_add_page(struct kimage *image, unsigned long page)
+{
+ int result;
+
+ page &= PAGE_MASK;
+ result = kimage_add_entry(image, page | IND_SOURCE);
+
+ return result;
+}
+
+
+static void kimage_free_extra_pages(struct kimage *image)
+{
+ /* Walk through and free any extra destination pages I may have */
+ kimage_free_page_list(&image->dest_pages);
+
+ /* Walk through and free any unusable pages I have cached */
+ kimage_free_page_list(&image->unusable_pages);
+
+}
+void kimage_terminate(struct kimage *image)
+{
+ if (*image->entry != 0)
+ image->entry++;
+
+ *image->entry = IND_DONE;
+}
+
+#define for_each_kimage_entry(image, ptr, entry) \
+ for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \
+ ptr = (entry & IND_INDIRECTION) ? \
+ phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
+
+static void kimage_free_entry(kimage_entry_t entry)
+{
+ struct page *page;
+
+ page = pfn_to_page(entry >> PAGE_SHIFT);
+ kimage_free_pages(page);
+}
+
+void kimage_free(struct kimage *image)
+{
+ kimage_entry_t *ptr, entry;
+ kimage_entry_t ind = 0;
+
+ if (!image)
+ return;
+
+ kimage_free_extra_pages(image);
+ for_each_kimage_entry(image, ptr, entry) {
+ if (entry & IND_INDIRECTION) {
+ /* Free the previous indirection page */
+ if (ind & IND_INDIRECTION)
+ kimage_free_entry(ind);
+ /* Save this indirection page until we are
+ * done with it.
+ */
+ ind = entry;
+ } else if (entry & IND_SOURCE)
+ kimage_free_entry(entry);
+ }
+ /* Free the final indirection page */
+ if (ind & IND_INDIRECTION)
+ kimage_free_entry(ind);
+
+ /* Handle any machine specific cleanup */
+ machine_kexec_cleanup(image);
+
+ /* Free the kexec control pages... */
+ kimage_free_page_list(&image->control_pages);
+
+ /*
+ * Free up any temporary buffers allocated. This might hit if
+ * error occurred much later after buffer allocation.
+ */
+ if (image->file_mode)
+ kimage_file_post_load_cleanup(image);
+
+ kfree(image);
+}
+
+static kimage_entry_t *kimage_dst_used(struct kimage *image,
+ unsigned long page)
+{
+ kimage_entry_t *ptr, entry;
+ unsigned long destination = 0;
+
+ for_each_kimage_entry(image, ptr, entry) {
+ if (entry & IND_DESTINATION)
+ destination = entry & PAGE_MASK;
+ else if (entry & IND_SOURCE) {
+ if (page == destination)
+ return ptr;
+ destination += PAGE_SIZE;
+ }
+ }
+
+ return NULL;
+}
+
+static struct page *kimage_alloc_page(struct kimage *image,
+ gfp_t gfp_mask,
+ unsigned long destination)
+{
+ /*
+ * Here we implement safeguards to ensure that a source page
+ * is not copied to its destination page before the data on
+ * the destination page is no longer useful.
+ *
+ * To do this we maintain the invariant that a source page is
+ * either its own destination page, or it is not a
+ * destination page at all.
+ *
+ * That is slightly stronger than required, but the proof
+ * that no problems will not occur is trivial, and the
+ * implementation is simply to verify.
+ *
+ * When allocating all pages normally this algorithm will run
+ * in O(N) time, but in the worst case it will run in O(N^2)
+ * time. If the runtime is a problem the data structures can
+ * be fixed.
+ */
+ struct page *page;
+ unsigned long addr;
+
+ /*
+ * Walk through the list of destination pages, and see if I
+ * have a match.
+ */
+ list_for_each_entry(page, &image->dest_pages, lru) {
+ addr = page_to_pfn(page) << PAGE_SHIFT;
+ if (addr == destination) {
+ list_del(&page->lru);
+ return page;
+ }
+ }
+ page = NULL;
+ while (1) {
+ kimage_entry_t *old;
+
+ /* Allocate a page, if we run out of memory give up */
+ page = kimage_alloc_pages(gfp_mask, 0);
+ if (!page)
+ return NULL;
+ /* If the page cannot be used file it away */
+ if (page_to_pfn(page) >
+ (KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) {
+ list_add(&page->lru, &image->unusable_pages);
+ continue;
+ }
+ addr = page_to_pfn(page) << PAGE_SHIFT;
+
+ /* If it is the destination page we want use it */
+ if (addr == destination)
+ break;
+
+ /* If the page is not a destination page use it */
+ if (!kimage_is_destination_range(image, addr,
+ addr + PAGE_SIZE))
+ break;
+
+ /*
+ * I know that the page is someones destination page.
+ * See if there is already a source page for this
+ * destination page. And if so swap the source pages.
+ */
+ old = kimage_dst_used(image, addr);
+ if (old) {
+ /* If so move it */
+ unsigned long old_addr;
+ struct page *old_page;
+
+ old_addr = *old & PAGE_MASK;
+ old_page = pfn_to_page(old_addr >> PAGE_SHIFT);
+ copy_highpage(page, old_page);
+ *old = addr | (*old & ~PAGE_MASK);
+
+ /* The old page I have found cannot be a
+ * destination page, so return it if it's
+ * gfp_flags honor the ones passed in.
+ */
+ if (!(gfp_mask & __GFP_HIGHMEM) &&
+ PageHighMem(old_page)) {
+ kimage_free_pages(old_page);
+ continue;
+ }
+ addr = old_addr;
+ page = old_page;
+ break;
+ } else {
+ /* Place the page on the destination list I
+ * will use it later.
+ */
+ list_add(&page->lru, &image->dest_pages);
+ }
+ }
+
+ return page;
+}
+
+static int kimage_load_normal_segment(struct kimage *image,
+ struct kexec_segment *segment)
+{
+ unsigned long maddr;
+ size_t ubytes, mbytes;
+ int result;
+ unsigned char __user *buf = NULL;
+ unsigned char *kbuf = NULL;
+
+ result = 0;
+ if (image->file_mode)
+ kbuf = segment->kbuf;
+ else
+ buf = segment->buf;
+ ubytes = segment->bufsz;
+ mbytes = segment->memsz;
+ maddr = segment->mem;
+
+ result = kimage_set_destination(image, maddr);
+ if (result < 0)
+ goto out;
+
+ while (mbytes) {
+ struct page *page;
+ char *ptr;
+ size_t uchunk, mchunk;
+
+ page = kimage_alloc_page(image, GFP_HIGHUSER, maddr);
+ if (!page) {
+ result = -ENOMEM;
+ goto out;
+ }
+ result = kimage_add_page(image, page_to_pfn(page)
+ << PAGE_SHIFT);
+ if (result < 0)
+ goto out;
+
+ ptr = kmap(page);
+ /* Start with a clear page */
+ clear_page(ptr);
+ ptr += maddr & ~PAGE_MASK;
+ mchunk = min_t(size_t, mbytes,
+ PAGE_SIZE - (maddr & ~PAGE_MASK));
+ uchunk = min(ubytes, mchunk);
+
+ /* For file based kexec, source pages are in kernel memory */
+ if (image->file_mode)
+ memcpy(ptr, kbuf, uchunk);
+ else
+ result = copy_from_user(ptr, buf, uchunk);
+ kunmap(page);
+ if (result) {
+ result = -EFAULT;
+ goto out;
+ }
+ ubytes -= uchunk;
+ maddr += mchunk;
+ if (image->file_mode)
+ kbuf += mchunk;
+ else
+ buf += mchunk;
+ mbytes -= mchunk;
+ }
+out:
+ return result;
+}
+
+static int kimage_load_crash_segment(struct kimage *image,
+ struct kexec_segment *segment)
+{
+ /* For crash dumps kernels we simply copy the data from
+ * user space to it's destination.
+ * We do things a page at a time for the sake of kmap.
+ */
+ unsigned long maddr;
+ size_t ubytes, mbytes;
+ int result;
+ unsigned char __user *buf = NULL;
+ unsigned char *kbuf = NULL;
+
+ result = 0;
+ if (image->file_mode)
+ kbuf = segment->kbuf;
+ else
+ buf = segment->buf;
+ ubytes = segment->bufsz;
+ mbytes = segment->memsz;
+ maddr = segment->mem;
+ while (mbytes) {
+ struct page *page;
+ char *ptr;
+ size_t uchunk, mchunk;
+
+ page = pfn_to_page(maddr >> PAGE_SHIFT);
+ if (!page) {
+ result = -ENOMEM;
+ goto out;
+ }
+ ptr = kmap(page);
+ ptr += maddr & ~PAGE_MASK;
+ mchunk = min_t(size_t, mbytes,
+ PAGE_SIZE - (maddr & ~PAGE_MASK));
+ uchunk = min(ubytes, mchunk);
+ if (mchunk > uchunk) {
+ /* Zero the trailing part of the page */
+ memset(ptr + uchunk, 0, mchunk - uchunk);
+ }
+
+ /* For file based kexec, source pages are in kernel memory */
+ if (image->file_mode)
+ memcpy(ptr, kbuf, uchunk);
+ else
+ result = copy_from_user(ptr, buf, uchunk);
+ kexec_flush_icache_page(page);
+ kunmap(page);
+ if (result) {
+ result = -EFAULT;
+ goto out;
+ }
+ ubytes -= uchunk;
+ maddr += mchunk;
+ if (image->file_mode)
+ kbuf += mchunk;
+ else
+ buf += mchunk;
+ mbytes -= mchunk;
+ }
+out:
+ return result;
+}
+
+int kimage_load_segment(struct kimage *image,
+ struct kexec_segment *segment)
+{
+ int result = -ENOMEM;
+
+ switch (image->type) {
+ case KEXEC_TYPE_DEFAULT:
+ result = kimage_load_normal_segment(image, segment);
+ break;
+ case KEXEC_TYPE_CRASH:
+ result = kimage_load_crash_segment(image, segment);
+ break;
+ }
+
+ return result;
+}
+
+struct kimage *kexec_image;
+struct kimage *kexec_crash_image;
+int kexec_load_disabled;
+
+void crash_kexec(struct pt_regs *regs)
+{
+ /* Take the kexec_mutex here to prevent sys_kexec_load
+ * running on one cpu from replacing the crash kernel
+ * we are using after a panic on a different cpu.
+ *
+ * If the crash kernel was not located in a fixed area
+ * of memory the xchg(&kexec_crash_image) would be
+ * sufficient. But since I reuse the memory...
+ */
+ if (mutex_trylock(&kexec_mutex)) {
+ if (kexec_crash_image) {
+ struct pt_regs fixed_regs;
+
+ crash_setup_regs(&fixed_regs, regs);
+ crash_save_vmcoreinfo();
+ machine_crash_shutdown(&fixed_regs);
+ machine_kexec(kexec_crash_image);
+ }
+ mutex_unlock(&kexec_mutex);
+ }
+}
+
+size_t crash_get_memory_size(void)
+{
+ size_t size = 0;
+ mutex_lock(&kexec_mutex);
+ if (crashk_res.end != crashk_res.start)
+ size = resource_size(&crashk_res);
+ mutex_unlock(&kexec_mutex);
+ return size;
+}
+
+void __weak crash_free_reserved_phys_range(unsigned long begin,
+ unsigned long end)
+{
+ unsigned long addr;
+
+ for (addr = begin; addr < end; addr += PAGE_SIZE)
+ free_reserved_page(pfn_to_page(addr >> PAGE_SHIFT));
+}
+
+int crash_shrink_memory(unsigned long new_size)
+{
+ int ret = 0;
+ unsigned long start, end;
+ unsigned long old_size;
+ struct resource *ram_res;
+
+ mutex_lock(&kexec_mutex);
+
+ if (kexec_crash_image) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+ start = crashk_res.start;
+ end = crashk_res.end;
+ old_size = (end == 0) ? 0 : end - start + 1;
+ if (new_size >= old_size) {
+ ret = (new_size == old_size) ? 0 : -EINVAL;
+ goto unlock;
+ }
+
+ ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
+ if (!ram_res) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+
+ start = roundup(start, KEXEC_CRASH_MEM_ALIGN);
+ end = roundup(start + new_size, KEXEC_CRASH_MEM_ALIGN);
+
+ crash_map_reserved_pages();
+ crash_free_reserved_phys_range(end, crashk_res.end);
+
+ if ((start == end) && (crashk_res.parent != NULL))
+ release_resource(&crashk_res);
+
+ ram_res->start = end;
+ ram_res->end = crashk_res.end;
+ ram_res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
+ ram_res->name = "System RAM";
+
+ crashk_res.end = end - 1;
+
+ insert_resource(&iomem_resource, ram_res);
+ crash_unmap_reserved_pages();
+
+unlock:
+ mutex_unlock(&kexec_mutex);
+ return ret;
+}
+
+static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
+ size_t data_len)
+{
+ struct elf_note note;
+
+ note.n_namesz = strlen(name) + 1;
+ note.n_descsz = data_len;
+ note.n_type = type;
+ memcpy(buf, ¬e, sizeof(note));
+ buf += (sizeof(note) + 3)/4;
+ memcpy(buf, name, note.n_namesz);
+ buf += (note.n_namesz + 3)/4;
+ memcpy(buf, data, note.n_descsz);
+ buf += (note.n_descsz + 3)/4;
+
+ return buf;
+}
+
+static void final_note(u32 *buf)
+{
+ struct elf_note note;
+
+ note.n_namesz = 0;
+ note.n_descsz = 0;
+ note.n_type = 0;
+ memcpy(buf, ¬e, sizeof(note));
+}
+
+void crash_save_cpu(struct pt_regs *regs, int cpu)
+{
+ struct elf_prstatus prstatus;
+ u32 *buf;
+
+ if ((cpu < 0) || (cpu >= nr_cpu_ids))
+ return;
+
+ /* Using ELF notes here is opportunistic.
+ * I need a well defined structure format
+ * for the data I pass, and I need tags
+ * on the data to indicate what information I have
+ * squirrelled away. ELF notes happen to provide
+ * all of that, so there is no need to invent something new.
+ */
+ buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
+ if (!buf)
+ return;
+ memset(&prstatus, 0, sizeof(prstatus));
+ prstatus.pr_pid = current->pid;
+ elf_core_copy_kernel_regs(&prstatus.pr_reg, regs);
+ buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
+ &prstatus, sizeof(prstatus));
+ final_note(buf);
+}
+
+static int __init crash_notes_memory_init(void)
+{
+ /* Allocate memory for saving cpu registers. */
+ crash_notes = alloc_percpu(note_buf_t);
+ if (!crash_notes) {
+ pr_warn("Kexec: Memory allocation for saving cpu register states failed\n");
+ return -ENOMEM;
+ }
+ return 0;
+}
+subsys_initcall(crash_notes_memory_init);
+
+
+/*
+ * parsing the "crashkernel" commandline
+ *
+ * this code is intended to be called from architecture specific code
+ */
+
+
+/*
+ * This function parses command lines in the format
+ *
+ * crashkernel=ramsize-range:size[,...][@offset]
+ *
+ * The function returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_mem(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ char *cur = cmdline, *tmp;
+
+ /* for each entry of the comma-separated list */
+ do {
+ unsigned long long start, end = ULLONG_MAX, size;
+
+ /* get the start of the range */
+ start = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("crashkernel: Memory value expected\n");
+ return -EINVAL;
+ }
+ cur = tmp;
+ if (*cur != '-') {
+ pr_warn("crashkernel: '-' expected\n");
+ return -EINVAL;
+ }
+ cur++;
+
+ /* if no ':' is here, than we read the end */
+ if (*cur != ':') {
+ end = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("crashkernel: Memory value expected\n");
+ return -EINVAL;
+ }
+ cur = tmp;
+ if (end <= start) {
+ pr_warn("crashkernel: end <= start\n");
+ return -EINVAL;
+ }
+ }
+
+ if (*cur != ':') {
+ pr_warn("crashkernel: ':' expected\n");
+ return -EINVAL;
+ }
+ cur++;
+
+ size = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("Memory value expected\n");
+ return -EINVAL;
+ }
+ cur = tmp;
+ if (size >= system_ram) {
+ pr_warn("crashkernel: invalid size\n");
+ return -EINVAL;
+ }
+
+ /* match ? */
+ if (system_ram >= start && system_ram < end) {
+ *crash_size = size;
+ break;
+ }
+ } while (*cur++ == ',');
+
+ if (*crash_size > 0) {
+ while (*cur && *cur != ' ' && *cur != '@')
+ cur++;
+ if (*cur == '@') {
+ cur++;
+ *crash_base = memparse(cur, &tmp);
+ if (cur == tmp) {
+ pr_warn("Memory value expected after '@'\n");
+ return -EINVAL;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * That function parses "simple" (old) crashkernel command lines like
+ *
+ * crashkernel=size[@offset]
+ *
+ * It returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_simple(char *cmdline,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ char *cur = cmdline;
+
+ *crash_size = memparse(cmdline, &cur);
+ if (cmdline == cur) {
+ pr_warn("crashkernel: memory value expected\n");
+ return -EINVAL;
+ }
+
+ if (*cur == '@')
+ *crash_base = memparse(cur+1, &cur);
+ else if (*cur != ' ' && *cur != '\0') {
+ pr_warn("crashkernel: unrecognized char\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+#define SUFFIX_HIGH 0
+#define SUFFIX_LOW 1
+#define SUFFIX_NULL 2
+static __initdata char *suffix_tbl[] = {
+ [SUFFIX_HIGH] = ",high",
+ [SUFFIX_LOW] = ",low",
+ [SUFFIX_NULL] = NULL,
+};
+
+/*
+ * That function parses "suffix" crashkernel command lines like
+ *
+ * crashkernel=size,[high|low]
+ *
+ * It returns 0 on success and -EINVAL on failure.
+ */
+static int __init parse_crashkernel_suffix(char *cmdline,
+ unsigned long long *crash_size,
+ const char *suffix)
+{
+ char *cur = cmdline;
+
+ *crash_size = memparse(cmdline, &cur);
+ if (cmdline == cur) {
+ pr_warn("crashkernel: memory value expected\n");
+ return -EINVAL;
+ }
+
+ /* check with suffix */
+ if (strncmp(cur, suffix, strlen(suffix))) {
+ pr_warn("crashkernel: unrecognized char\n");
+ return -EINVAL;
+ }
+ cur += strlen(suffix);
+ if (*cur != ' ' && *cur != '\0') {
+ pr_warn("crashkernel: unrecognized char\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static __init char *get_last_crashkernel(char *cmdline,
+ const char *name,
+ const char *suffix)
+{
+ char *p = cmdline, *ck_cmdline = NULL;
+
+ /* find crashkernel and use the last one if there are more */
+ p = strstr(p, name);
+ while (p) {
+ char *end_p = strchr(p, ' ');
+ char *q;
+
+ if (!end_p)
+ end_p = p + strlen(p);
+
+ if (!suffix) {
+ int i;
+
+ /* skip the one with any known suffix */
+ for (i = 0; suffix_tbl[i]; i++) {
+ q = end_p - strlen(suffix_tbl[i]);
+ if (!strncmp(q, suffix_tbl[i],
+ strlen(suffix_tbl[i])))
+ goto next;
+ }
+ ck_cmdline = p;
+ } else {
+ q = end_p - strlen(suffix);
+ if (!strncmp(q, suffix, strlen(suffix)))
+ ck_cmdline = p;
+ }
+next:
+ p = strstr(p+1, name);
+ }
+
+ if (!ck_cmdline)
+ return NULL;
+
+ return ck_cmdline;
+}
+
+static int __init __parse_crashkernel(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base,
+ const char *name,
+ const char *suffix)
+{
+ char *first_colon, *first_space;
+ char *ck_cmdline;
+
+ BUG_ON(!crash_size || !crash_base);
+ *crash_size = 0;
+ *crash_base = 0;
+
+ ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
+
+ if (!ck_cmdline)
+ return -EINVAL;
+
+ ck_cmdline += strlen(name);
+
+ if (suffix)
+ return parse_crashkernel_suffix(ck_cmdline, crash_size,
+ suffix);
+ /*
+ * if the commandline contains a ':', then that's the extended
+ * syntax -- if not, it must be the classic syntax
+ */
+ first_colon = strchr(ck_cmdline, ':');
+ first_space = strchr(ck_cmdline, ' ');
+ if (first_colon && (!first_space || first_colon < first_space))
+ return parse_crashkernel_mem(ck_cmdline, system_ram,
+ crash_size, crash_base);
+
+ return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base);
+}
+
+/*
+ * That function is the entry point for command line parsing and should be
+ * called from the arch-specific code.
+ */
+int __init parse_crashkernel(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+ "crashkernel=", NULL);
+}
+
+int __init parse_crashkernel_high(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+ "crashkernel=", suffix_tbl[SUFFIX_HIGH]);
+}
+
+int __init parse_crashkernel_low(char *cmdline,
+ unsigned long long system_ram,
+ unsigned long long *crash_size,
+ unsigned long long *crash_base)
+{
+ return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
+ "crashkernel=", suffix_tbl[SUFFIX_LOW]);
+}
+
+static void update_vmcoreinfo_note(void)
+{
+ u32 *buf = vmcoreinfo_note;
+
+ if (!vmcoreinfo_size)
+ return;
+ buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
+ vmcoreinfo_size);
+ final_note(buf);
+}
+
+void crash_save_vmcoreinfo(void)
+{
+ vmcoreinfo_append_str("CRASHTIME=%ld\n", get_seconds());
+ update_vmcoreinfo_note();
+}
+
+void vmcoreinfo_append_str(const char *fmt, ...)
+{
+ va_list args;
+ char buf[0x50];
+ size_t r;
+
+ va_start(args, fmt);
+ r = vscnprintf(buf, sizeof(buf), fmt, args);
+ va_end(args);
+
+ r = min(r, vmcoreinfo_max_size - vmcoreinfo_size);
+
+ memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
+
+ vmcoreinfo_size += r;
+}
+
+/*
+ * provide an empty default implementation here -- architecture
+ * code may override this
+ */
+void __weak arch_crash_save_vmcoreinfo(void)
+{}
+
+unsigned long __weak paddr_vmcoreinfo_note(void)
+{
+ return __pa((unsigned long)(char *)&vmcoreinfo_note);
+}
+
+static int __init crash_save_vmcoreinfo_init(void)
+{
+ VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
+ VMCOREINFO_PAGESIZE(PAGE_SIZE);
+
+ VMCOREINFO_SYMBOL(init_uts_ns);
+ VMCOREINFO_SYMBOL(node_online_map);
+#ifdef CONFIG_MMU
+ VMCOREINFO_SYMBOL(swapper_pg_dir);
+#endif
+ VMCOREINFO_SYMBOL(_stext);
+ VMCOREINFO_SYMBOL(vmap_area_list);
+
+#ifndef CONFIG_NEED_MULTIPLE_NODES
+ VMCOREINFO_SYMBOL(mem_map);
+ VMCOREINFO_SYMBOL(contig_page_data);
+#endif
+#ifdef CONFIG_SPARSEMEM
+ VMCOREINFO_SYMBOL(mem_section);
+ VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
+ VMCOREINFO_STRUCT_SIZE(mem_section);
+ VMCOREINFO_OFFSET(mem_section, section_mem_map);
+#endif
+ VMCOREINFO_STRUCT_SIZE(page);
+ VMCOREINFO_STRUCT_SIZE(pglist_data);
+ VMCOREINFO_STRUCT_SIZE(zone);
+ VMCOREINFO_STRUCT_SIZE(free_area);
+ VMCOREINFO_STRUCT_SIZE(list_head);
+ VMCOREINFO_SIZE(nodemask_t);
+ VMCOREINFO_OFFSET(page, flags);
+ VMCOREINFO_OFFSET(page, _count);
+ VMCOREINFO_OFFSET(page, mapping);
+ VMCOREINFO_OFFSET(page, lru);
+ VMCOREINFO_OFFSET(page, _mapcount);
+ VMCOREINFO_OFFSET(page, private);
+ VMCOREINFO_OFFSET(pglist_data, node_zones);
+ VMCOREINFO_OFFSET(pglist_data, nr_zones);
+#ifdef CONFIG_FLAT_NODE_MEM_MAP
+ VMCOREINFO_OFFSET(pglist_data, node_mem_map);
+#endif
+ VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
+ VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
+ VMCOREINFO_OFFSET(pglist_data, node_id);
+ VMCOREINFO_OFFSET(zone, free_area);
+ VMCOREINFO_OFFSET(zone, vm_stat);
+ VMCOREINFO_OFFSET(zone, spanned_pages);
+ VMCOREINFO_OFFSET(free_area, free_list);
+ VMCOREINFO_OFFSET(list_head, next);
+ VMCOREINFO_OFFSET(list_head, prev);
+ VMCOREINFO_OFFSET(vmap_area, va_start);
+ VMCOREINFO_OFFSET(vmap_area, list);
+ VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);
+ log_buf_kexec_setup();
+ VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
+ VMCOREINFO_NUMBER(NR_FREE_PAGES);
+ VMCOREINFO_NUMBER(PG_lru);
+ VMCOREINFO_NUMBER(PG_private);
+ VMCOREINFO_NUMBER(PG_swapcache);
+ VMCOREINFO_NUMBER(PG_slab);
+#ifdef CONFIG_MEMORY_FAILURE
+ VMCOREINFO_NUMBER(PG_hwpoison);
+#endif
+ VMCOREINFO_NUMBER(PG_head_mask);
+ VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
+#ifdef CONFIG_HUGETLBFS
+ VMCOREINFO_SYMBOL(free_huge_page);
+#endif
+
+ arch_crash_save_vmcoreinfo();
+ update_vmcoreinfo_note();
+
+ return 0;
+}
+
+subsys_initcall(crash_save_vmcoreinfo_init);
+
+/*
+ * Move into place and start executing a preloaded standalone
+ * executable. If nothing was preloaded return an error.
+ */
+int kernel_kexec(void)
+{
+ int error = 0;
+
+ if (!mutex_trylock(&kexec_mutex))
+ return -EBUSY;
+ if (!kexec_image) {
+ error = -EINVAL;
+ goto Unlock;
+ }
+
+#ifdef CONFIG_KEXEC_JUMP
+ if (kexec_image->preserve_context) {
+ lock_system_sleep();
+ pm_prepare_console();
+ error = freeze_processes();
+ if (error) {
+ error = -EBUSY;
+ goto Restore_console;
+ }
+ suspend_console();
+ error = dpm_suspend_start(PMSG_FREEZE);
+ if (error)
+ goto Resume_console;
+ /* At this point, dpm_suspend_start() has been called,
+ * but *not* dpm_suspend_end(). We *must* call
+ * dpm_suspend_end() now. Otherwise, drivers for
+ * some devices (e.g. interrupt controllers) become
+ * desynchronized with the actual state of the
+ * hardware at resume time, and evil weirdness ensues.
+ */
+ error = dpm_suspend_end(PMSG_FREEZE);
+ if (error)
+ goto Resume_devices;
+ error = disable_nonboot_cpus();
+ if (error)
+ goto Enable_cpus;
+ local_irq_disable();
+ error = syscore_suspend();
+ if (error)
+ goto Enable_irqs;
+ } else
+#endif
+ {
+ kexec_in_progress = true;
+ kernel_restart_prepare(NULL);
+ migrate_to_reboot_cpu();
+
+ /*
+ * migrate_to_reboot_cpu() disables CPU hotplug assuming that
+ * no further code needs to use CPU hotplug (which is true in
+ * the reboot case). However, the kexec path depends on using
+ * CPU hotplug again; so re-enable it here.
+ */
+ cpu_hotplug_enable();
+ pr_emerg("Starting new kernel\n");
+ machine_shutdown();
+ }
+
+ machine_kexec(kexec_image);
+
+#ifdef CONFIG_KEXEC_JUMP
+ if (kexec_image->preserve_context) {
+ syscore_resume();
+ Enable_irqs:
+ local_irq_enable();
+ Enable_cpus:
+ enable_nonboot_cpus();
+ dpm_resume_start(PMSG_RESTORE);
+ Resume_devices:
+ dpm_resume_end(PMSG_RESTORE);
+ Resume_console:
+ resume_console();
+ thaw_processes();
+ Restore_console:
+ pm_restore_console();
+ unlock_system_sleep();
+ }
+#endif
+
+ Unlock:
+ mutex_unlock(&kexec_mutex);
+ return error;
+}
+
+/*
+ * Add and remove page tables for crashkernel memory
+ *
+ * Provide an empty default implementation here -- architecture
+ * code may override this
+ */
+void __weak crash_map_reserved_pages(void)
+{}
+
+void __weak crash_unmap_reserved_pages(void)
+{}
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 6683cce..e83b264 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -90,7 +90,7 @@ static ssize_t profiling_store(struct kobject *kobj,
KERNEL_ATTR_RW(profiling);
#endif
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
static ssize_t kexec_loaded_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
@@ -134,7 +134,7 @@ static ssize_t vmcoreinfo_show(struct kobject *kobj,
}
KERNEL_ATTR_RO(vmcoreinfo);
-#endif /* CONFIG_KEXEC */
+#endif /* CONFIG_KEXEC_CORE */
/* whether file capabilities are enabled */
static ssize_t fscaps_show(struct kobject *kobj,
@@ -196,7 +196,7 @@ static struct attribute * kernel_attrs[] = {
#ifdef CONFIG_PROFILING
&profiling_attr.attr,
#endif
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
&kexec_loaded_attr.attr,
&kexec_crash_loaded_attr.attr,
&kexec_crash_size_attr.attr,
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index cf8c242..8f0324e 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -835,7 +835,7 @@ const struct file_operations kmsg_fops = {
.release = devkmsg_release,
};
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
/*
* This appends the listed symbols to /proc/vmcore
*
diff --git a/kernel/reboot.c b/kernel/reboot.c
index d20c85d..bd30a97 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -346,7 +346,7 @@ SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd,
kernel_restart(buffer);
break;
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
case LINUX_REBOOT_CMD_KEXEC:
ret = kernel_kexec();
break;
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 19b62b5..715cc57 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -621,7 +621,7 @@ static struct ctl_table kern_table[] = {
.proc_handler = proc_dointvec,
},
#endif
-#ifdef CONFIG_KEXEC
+#ifdef CONFIG_KEXEC_CORE
{
.procname = "kexec_load_disabled",
.data = &kexec_load_disabled,
--
1.8.3.1
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