Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1 | /* |
| 2 | * kexec.c - kexec system call |
| 3 | * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com> |
| 4 | * |
| 5 | * This source code is licensed under the GNU General Public License, |
| 6 | * Version 2. See the file COPYING for more details. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/mm.h> |
| 10 | #include <linux/file.h> |
| 11 | #include <linux/slab.h> |
| 12 | #include <linux/fs.h> |
| 13 | #include <linux/kexec.h> |
| 14 | #include <linux/spinlock.h> |
| 15 | #include <linux/list.h> |
| 16 | #include <linux/highmem.h> |
| 17 | #include <linux/syscalls.h> |
| 18 | #include <linux/reboot.h> |
| 19 | #include <linux/syscalls.h> |
| 20 | #include <linux/ioport.h> |
Alexander Nyberg | 6e274d1 | 2005-06-25 14:58:26 -0700 | [diff] [blame] | 21 | #include <linux/hardirq.h> |
| 22 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 23 | #include <asm/page.h> |
| 24 | #include <asm/uaccess.h> |
| 25 | #include <asm/io.h> |
| 26 | #include <asm/system.h> |
| 27 | #include <asm/semaphore.h> |
| 28 | |
| 29 | /* Location of the reserved area for the crash kernel */ |
| 30 | struct resource crashk_res = { |
| 31 | .name = "Crash kernel", |
| 32 | .start = 0, |
| 33 | .end = 0, |
| 34 | .flags = IORESOURCE_BUSY | IORESOURCE_MEM |
| 35 | }; |
| 36 | |
Alexander Nyberg | 6e274d1 | 2005-06-25 14:58:26 -0700 | [diff] [blame] | 37 | int kexec_should_crash(struct task_struct *p) |
| 38 | { |
| 39 | if (in_interrupt() || !p->pid || p->pid == 1 || panic_on_oops) |
| 40 | return 1; |
| 41 | return 0; |
| 42 | } |
| 43 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 44 | /* |
| 45 | * When kexec transitions to the new kernel there is a one-to-one |
| 46 | * mapping between physical and virtual addresses. On processors |
| 47 | * where you can disable the MMU this is trivial, and easy. For |
| 48 | * others it is still a simple predictable page table to setup. |
| 49 | * |
| 50 | * In that environment kexec copies the new kernel to its final |
| 51 | * resting place. This means I can only support memory whose |
| 52 | * physical address can fit in an unsigned long. In particular |
| 53 | * addresses where (pfn << PAGE_SHIFT) > ULONG_MAX cannot be handled. |
| 54 | * If the assembly stub has more restrictive requirements |
| 55 | * KEXEC_SOURCE_MEMORY_LIMIT and KEXEC_DEST_MEMORY_LIMIT can be |
| 56 | * defined more restrictively in <asm/kexec.h>. |
| 57 | * |
| 58 | * The code for the transition from the current kernel to the |
| 59 | * the new kernel is placed in the control_code_buffer, whose size |
| 60 | * is given by KEXEC_CONTROL_CODE_SIZE. In the best case only a single |
| 61 | * page of memory is necessary, but some architectures require more. |
| 62 | * Because this memory must be identity mapped in the transition from |
| 63 | * virtual to physical addresses it must live in the range |
| 64 | * 0 - TASK_SIZE, as only the user space mappings are arbitrarily |
| 65 | * modifiable. |
| 66 | * |
| 67 | * The assembly stub in the control code buffer is passed a linked list |
| 68 | * of descriptor pages detailing the source pages of the new kernel, |
| 69 | * and the destination addresses of those source pages. As this data |
| 70 | * structure is not used in the context of the current OS, it must |
| 71 | * be self-contained. |
| 72 | * |
| 73 | * The code has been made to work with highmem pages and will use a |
| 74 | * destination page in its final resting place (if it happens |
| 75 | * to allocate it). The end product of this is that most of the |
| 76 | * physical address space, and most of RAM can be used. |
| 77 | * |
| 78 | * Future directions include: |
| 79 | * - allocating a page table with the control code buffer identity |
| 80 | * mapped, to simplify machine_kexec and make kexec_on_panic more |
| 81 | * reliable. |
| 82 | */ |
| 83 | |
| 84 | /* |
| 85 | * KIMAGE_NO_DEST is an impossible destination address..., for |
| 86 | * allocating pages whose destination address we do not care about. |
| 87 | */ |
| 88 | #define KIMAGE_NO_DEST (-1UL) |
| 89 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 90 | static int kimage_is_destination_range(struct kimage *image, |
| 91 | unsigned long start, unsigned long end); |
| 92 | static struct page *kimage_alloc_page(struct kimage *image, |
Al Viro | 9796fdd | 2005-10-21 03:22:03 -0400 | [diff] [blame] | 93 | gfp_t gfp_mask, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 94 | unsigned long dest); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 95 | |
| 96 | static int do_kimage_alloc(struct kimage **rimage, unsigned long entry, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 97 | unsigned long nr_segments, |
| 98 | struct kexec_segment __user *segments) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 99 | { |
| 100 | size_t segment_bytes; |
| 101 | struct kimage *image; |
| 102 | unsigned long i; |
| 103 | int result; |
| 104 | |
| 105 | /* Allocate a controlling structure */ |
| 106 | result = -ENOMEM; |
| 107 | image = kmalloc(sizeof(*image), GFP_KERNEL); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 108 | if (!image) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 109 | goto out; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 110 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 111 | memset(image, 0, sizeof(*image)); |
| 112 | image->head = 0; |
| 113 | image->entry = &image->head; |
| 114 | image->last_entry = &image->head; |
| 115 | image->control_page = ~0; /* By default this does not apply */ |
| 116 | image->start = entry; |
| 117 | image->type = KEXEC_TYPE_DEFAULT; |
| 118 | |
| 119 | /* Initialize the list of control pages */ |
| 120 | INIT_LIST_HEAD(&image->control_pages); |
| 121 | |
| 122 | /* Initialize the list of destination pages */ |
| 123 | INIT_LIST_HEAD(&image->dest_pages); |
| 124 | |
| 125 | /* Initialize the list of unuseable pages */ |
| 126 | INIT_LIST_HEAD(&image->unuseable_pages); |
| 127 | |
| 128 | /* Read in the segments */ |
| 129 | image->nr_segments = nr_segments; |
| 130 | segment_bytes = nr_segments * sizeof(*segments); |
| 131 | result = copy_from_user(image->segment, segments, segment_bytes); |
| 132 | if (result) |
| 133 | goto out; |
| 134 | |
| 135 | /* |
| 136 | * Verify we have good destination addresses. The caller is |
| 137 | * responsible for making certain we don't attempt to load |
| 138 | * the new image into invalid or reserved areas of RAM. This |
| 139 | * just verifies it is an address we can use. |
| 140 | * |
| 141 | * Since the kernel does everything in page size chunks ensure |
| 142 | * the destination addreses are page aligned. Too many |
| 143 | * special cases crop of when we don't do this. The most |
| 144 | * insidious is getting overlapping destination addresses |
| 145 | * simply because addresses are changed to page size |
| 146 | * granularity. |
| 147 | */ |
| 148 | result = -EADDRNOTAVAIL; |
| 149 | for (i = 0; i < nr_segments; i++) { |
| 150 | unsigned long mstart, mend; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 151 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 152 | mstart = image->segment[i].mem; |
| 153 | mend = mstart + image->segment[i].memsz; |
| 154 | if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK)) |
| 155 | goto out; |
| 156 | if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT) |
| 157 | goto out; |
| 158 | } |
| 159 | |
| 160 | /* Verify our destination addresses do not overlap. |
| 161 | * If we alloed overlapping destination addresses |
| 162 | * through very weird things can happen with no |
| 163 | * easy explanation as one segment stops on another. |
| 164 | */ |
| 165 | result = -EINVAL; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 166 | for (i = 0; i < nr_segments; i++) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 167 | unsigned long mstart, mend; |
| 168 | unsigned long j; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 169 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 170 | mstart = image->segment[i].mem; |
| 171 | mend = mstart + image->segment[i].memsz; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 172 | for (j = 0; j < i; j++) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 173 | unsigned long pstart, pend; |
| 174 | pstart = image->segment[j].mem; |
| 175 | pend = pstart + image->segment[j].memsz; |
| 176 | /* Do the segments overlap ? */ |
| 177 | if ((mend > pstart) && (mstart < pend)) |
| 178 | goto out; |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | /* Ensure our buffer sizes are strictly less than |
| 183 | * our memory sizes. This should always be the case, |
| 184 | * and it is easier to check up front than to be surprised |
| 185 | * later on. |
| 186 | */ |
| 187 | result = -EINVAL; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 188 | for (i = 0; i < nr_segments; i++) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 189 | if (image->segment[i].bufsz > image->segment[i].memsz) |
| 190 | goto out; |
| 191 | } |
| 192 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 193 | result = 0; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 194 | out: |
| 195 | if (result == 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 196 | *rimage = image; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 197 | else |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 198 | kfree(image); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 199 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 200 | return result; |
| 201 | |
| 202 | } |
| 203 | |
| 204 | static int kimage_normal_alloc(struct kimage **rimage, unsigned long entry, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 205 | unsigned long nr_segments, |
| 206 | struct kexec_segment __user *segments) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 207 | { |
| 208 | int result; |
| 209 | struct kimage *image; |
| 210 | |
| 211 | /* Allocate and initialize a controlling structure */ |
| 212 | image = NULL; |
| 213 | result = do_kimage_alloc(&image, entry, nr_segments, segments); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 214 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 215 | goto out; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 216 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 217 | *rimage = image; |
| 218 | |
| 219 | /* |
| 220 | * Find a location for the control code buffer, and add it |
| 221 | * the vector of segments so that it's pages will also be |
| 222 | * counted as destination pages. |
| 223 | */ |
| 224 | result = -ENOMEM; |
| 225 | image->control_code_page = kimage_alloc_control_pages(image, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 226 | get_order(KEXEC_CONTROL_CODE_SIZE)); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 227 | if (!image->control_code_page) { |
| 228 | printk(KERN_ERR "Could not allocate control_code_buffer\n"); |
| 229 | goto out; |
| 230 | } |
| 231 | |
| 232 | result = 0; |
| 233 | out: |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 234 | if (result == 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 235 | *rimage = image; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 236 | else |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 237 | kfree(image); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 238 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 239 | return result; |
| 240 | } |
| 241 | |
| 242 | static int kimage_crash_alloc(struct kimage **rimage, unsigned long entry, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 243 | unsigned long nr_segments, |
Alexey Dobriyan | 314b6a4 | 2005-06-27 22:29:33 -0700 | [diff] [blame] | 244 | struct kexec_segment __user *segments) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 245 | { |
| 246 | int result; |
| 247 | struct kimage *image; |
| 248 | unsigned long i; |
| 249 | |
| 250 | image = NULL; |
| 251 | /* Verify we have a valid entry point */ |
| 252 | if ((entry < crashk_res.start) || (entry > crashk_res.end)) { |
| 253 | result = -EADDRNOTAVAIL; |
| 254 | goto out; |
| 255 | } |
| 256 | |
| 257 | /* Allocate and initialize a controlling structure */ |
| 258 | result = do_kimage_alloc(&image, entry, nr_segments, segments); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 259 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 260 | goto out; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 261 | |
| 262 | /* Enable the special crash kernel control page |
| 263 | * allocation policy. |
| 264 | */ |
| 265 | image->control_page = crashk_res.start; |
| 266 | image->type = KEXEC_TYPE_CRASH; |
| 267 | |
| 268 | /* |
| 269 | * Verify we have good destination addresses. Normally |
| 270 | * the caller is responsible for making certain we don't |
| 271 | * attempt to load the new image into invalid or reserved |
| 272 | * areas of RAM. But crash kernels are preloaded into a |
| 273 | * reserved area of ram. We must ensure the addresses |
| 274 | * are in the reserved area otherwise preloading the |
| 275 | * kernel could corrupt things. |
| 276 | */ |
| 277 | result = -EADDRNOTAVAIL; |
| 278 | for (i = 0; i < nr_segments; i++) { |
| 279 | unsigned long mstart, mend; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 280 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 281 | mstart = image->segment[i].mem; |
Vivek Goyal | 50cccc6 | 2005-06-25 14:57:55 -0700 | [diff] [blame] | 282 | mend = mstart + image->segment[i].memsz - 1; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 283 | /* Ensure we are within the crash kernel limits */ |
| 284 | if ((mstart < crashk_res.start) || (mend > crashk_res.end)) |
| 285 | goto out; |
| 286 | } |
| 287 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 288 | /* |
| 289 | * Find a location for the control code buffer, and add |
| 290 | * the vector of segments so that it's pages will also be |
| 291 | * counted as destination pages. |
| 292 | */ |
| 293 | result = -ENOMEM; |
| 294 | image->control_code_page = kimage_alloc_control_pages(image, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 295 | get_order(KEXEC_CONTROL_CODE_SIZE)); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 296 | if (!image->control_code_page) { |
| 297 | printk(KERN_ERR "Could not allocate control_code_buffer\n"); |
| 298 | goto out; |
| 299 | } |
| 300 | |
| 301 | result = 0; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 302 | out: |
| 303 | if (result == 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 304 | *rimage = image; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 305 | else |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 306 | kfree(image); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 307 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 308 | return result; |
| 309 | } |
| 310 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 311 | static int kimage_is_destination_range(struct kimage *image, |
| 312 | unsigned long start, |
| 313 | unsigned long end) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 314 | { |
| 315 | unsigned long i; |
| 316 | |
| 317 | for (i = 0; i < image->nr_segments; i++) { |
| 318 | unsigned long mstart, mend; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 319 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 320 | mstart = image->segment[i].mem; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 321 | mend = mstart + image->segment[i].memsz; |
| 322 | if ((end > mstart) && (start < mend)) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 323 | return 1; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 324 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 325 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 326 | return 0; |
| 327 | } |
| 328 | |
Al Viro | 9796fdd | 2005-10-21 03:22:03 -0400 | [diff] [blame] | 329 | static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 330 | { |
| 331 | struct page *pages; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 332 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 333 | pages = alloc_pages(gfp_mask, order); |
| 334 | if (pages) { |
| 335 | unsigned int count, i; |
| 336 | pages->mapping = NULL; |
Hugh Dickins | 4c21e2f | 2005-10-29 18:16:40 -0700 | [diff] [blame] | 337 | set_page_private(pages, order); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 338 | count = 1 << order; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 339 | for (i = 0; i < count; i++) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 340 | SetPageReserved(pages + i); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 341 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 342 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 343 | return pages; |
| 344 | } |
| 345 | |
| 346 | static void kimage_free_pages(struct page *page) |
| 347 | { |
| 348 | unsigned int order, count, i; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 349 | |
Hugh Dickins | 4c21e2f | 2005-10-29 18:16:40 -0700 | [diff] [blame] | 350 | order = page_private(page); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 351 | count = 1 << order; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 352 | for (i = 0; i < count; i++) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 353 | ClearPageReserved(page + i); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 354 | __free_pages(page, order); |
| 355 | } |
| 356 | |
| 357 | static void kimage_free_page_list(struct list_head *list) |
| 358 | { |
| 359 | struct list_head *pos, *next; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 360 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 361 | list_for_each_safe(pos, next, list) { |
| 362 | struct page *page; |
| 363 | |
| 364 | page = list_entry(pos, struct page, lru); |
| 365 | list_del(&page->lru); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 366 | kimage_free_pages(page); |
| 367 | } |
| 368 | } |
| 369 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 370 | static struct page *kimage_alloc_normal_control_pages(struct kimage *image, |
| 371 | unsigned int order) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 372 | { |
| 373 | /* Control pages are special, they are the intermediaries |
| 374 | * that are needed while we copy the rest of the pages |
| 375 | * to their final resting place. As such they must |
| 376 | * not conflict with either the destination addresses |
| 377 | * or memory the kernel is already using. |
| 378 | * |
| 379 | * The only case where we really need more than one of |
| 380 | * these are for architectures where we cannot disable |
| 381 | * the MMU and must instead generate an identity mapped |
| 382 | * page table for all of the memory. |
| 383 | * |
| 384 | * At worst this runs in O(N) of the image size. |
| 385 | */ |
| 386 | struct list_head extra_pages; |
| 387 | struct page *pages; |
| 388 | unsigned int count; |
| 389 | |
| 390 | count = 1 << order; |
| 391 | INIT_LIST_HEAD(&extra_pages); |
| 392 | |
| 393 | /* Loop while I can allocate a page and the page allocated |
| 394 | * is a destination page. |
| 395 | */ |
| 396 | do { |
| 397 | unsigned long pfn, epfn, addr, eaddr; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 398 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 399 | pages = kimage_alloc_pages(GFP_KERNEL, order); |
| 400 | if (!pages) |
| 401 | break; |
| 402 | pfn = page_to_pfn(pages); |
| 403 | epfn = pfn + count; |
| 404 | addr = pfn << PAGE_SHIFT; |
| 405 | eaddr = epfn << PAGE_SHIFT; |
| 406 | if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) || |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 407 | kimage_is_destination_range(image, addr, eaddr)) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 408 | list_add(&pages->lru, &extra_pages); |
| 409 | pages = NULL; |
| 410 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 411 | } while (!pages); |
| 412 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 413 | if (pages) { |
| 414 | /* Remember the allocated page... */ |
| 415 | list_add(&pages->lru, &image->control_pages); |
| 416 | |
| 417 | /* Because the page is already in it's destination |
| 418 | * location we will never allocate another page at |
| 419 | * that address. Therefore kimage_alloc_pages |
| 420 | * will not return it (again) and we don't need |
| 421 | * to give it an entry in image->segment[]. |
| 422 | */ |
| 423 | } |
| 424 | /* Deal with the destination pages I have inadvertently allocated. |
| 425 | * |
| 426 | * Ideally I would convert multi-page allocations into single |
| 427 | * page allocations, and add everyting to image->dest_pages. |
| 428 | * |
| 429 | * For now it is simpler to just free the pages. |
| 430 | */ |
| 431 | kimage_free_page_list(&extra_pages); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 432 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 433 | return pages; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 434 | } |
| 435 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 436 | static struct page *kimage_alloc_crash_control_pages(struct kimage *image, |
| 437 | unsigned int order) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 438 | { |
| 439 | /* Control pages are special, they are the intermediaries |
| 440 | * that are needed while we copy the rest of the pages |
| 441 | * to their final resting place. As such they must |
| 442 | * not conflict with either the destination addresses |
| 443 | * or memory the kernel is already using. |
| 444 | * |
| 445 | * Control pages are also the only pags we must allocate |
| 446 | * when loading a crash kernel. All of the other pages |
| 447 | * are specified by the segments and we just memcpy |
| 448 | * into them directly. |
| 449 | * |
| 450 | * The only case where we really need more than one of |
| 451 | * these are for architectures where we cannot disable |
| 452 | * the MMU and must instead generate an identity mapped |
| 453 | * page table for all of the memory. |
| 454 | * |
| 455 | * Given the low demand this implements a very simple |
| 456 | * allocator that finds the first hole of the appropriate |
| 457 | * size in the reserved memory region, and allocates all |
| 458 | * of the memory up to and including the hole. |
| 459 | */ |
| 460 | unsigned long hole_start, hole_end, size; |
| 461 | struct page *pages; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 462 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 463 | pages = NULL; |
| 464 | size = (1 << order) << PAGE_SHIFT; |
| 465 | hole_start = (image->control_page + (size - 1)) & ~(size - 1); |
| 466 | hole_end = hole_start + size - 1; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 467 | while (hole_end <= crashk_res.end) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 468 | unsigned long i; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 469 | |
| 470 | if (hole_end > KEXEC_CONTROL_MEMORY_LIMIT) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 471 | break; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 472 | if (hole_end > crashk_res.end) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 473 | break; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 474 | /* See if I overlap any of the segments */ |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 475 | for (i = 0; i < image->nr_segments; i++) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 476 | unsigned long mstart, mend; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 477 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 478 | mstart = image->segment[i].mem; |
| 479 | mend = mstart + image->segment[i].memsz - 1; |
| 480 | if ((hole_end >= mstart) && (hole_start <= mend)) { |
| 481 | /* Advance the hole to the end of the segment */ |
| 482 | hole_start = (mend + (size - 1)) & ~(size - 1); |
| 483 | hole_end = hole_start + size - 1; |
| 484 | break; |
| 485 | } |
| 486 | } |
| 487 | /* If I don't overlap any segments I have found my hole! */ |
| 488 | if (i == image->nr_segments) { |
| 489 | pages = pfn_to_page(hole_start >> PAGE_SHIFT); |
| 490 | break; |
| 491 | } |
| 492 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 493 | if (pages) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 494 | image->control_page = hole_end; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 495 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 496 | return pages; |
| 497 | } |
| 498 | |
| 499 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 500 | struct page *kimage_alloc_control_pages(struct kimage *image, |
| 501 | unsigned int order) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 502 | { |
| 503 | struct page *pages = NULL; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 504 | |
| 505 | switch (image->type) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 506 | case KEXEC_TYPE_DEFAULT: |
| 507 | pages = kimage_alloc_normal_control_pages(image, order); |
| 508 | break; |
| 509 | case KEXEC_TYPE_CRASH: |
| 510 | pages = kimage_alloc_crash_control_pages(image, order); |
| 511 | break; |
| 512 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 513 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 514 | return pages; |
| 515 | } |
| 516 | |
| 517 | static int kimage_add_entry(struct kimage *image, kimage_entry_t entry) |
| 518 | { |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 519 | if (*image->entry != 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 520 | image->entry++; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 521 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 522 | if (image->entry == image->last_entry) { |
| 523 | kimage_entry_t *ind_page; |
| 524 | struct page *page; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 525 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 526 | page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 527 | if (!page) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 528 | return -ENOMEM; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 529 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 530 | ind_page = page_address(page); |
| 531 | *image->entry = virt_to_phys(ind_page) | IND_INDIRECTION; |
| 532 | image->entry = ind_page; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 533 | image->last_entry = ind_page + |
| 534 | ((PAGE_SIZE/sizeof(kimage_entry_t)) - 1); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 535 | } |
| 536 | *image->entry = entry; |
| 537 | image->entry++; |
| 538 | *image->entry = 0; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 539 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 540 | return 0; |
| 541 | } |
| 542 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 543 | static int kimage_set_destination(struct kimage *image, |
| 544 | unsigned long destination) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 545 | { |
| 546 | int result; |
| 547 | |
| 548 | destination &= PAGE_MASK; |
| 549 | result = kimage_add_entry(image, destination | IND_DESTINATION); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 550 | if (result == 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 551 | image->destination = destination; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 552 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 553 | return result; |
| 554 | } |
| 555 | |
| 556 | |
| 557 | static int kimage_add_page(struct kimage *image, unsigned long page) |
| 558 | { |
| 559 | int result; |
| 560 | |
| 561 | page &= PAGE_MASK; |
| 562 | result = kimage_add_entry(image, page | IND_SOURCE); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 563 | if (result == 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 564 | image->destination += PAGE_SIZE; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 565 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 566 | return result; |
| 567 | } |
| 568 | |
| 569 | |
| 570 | static void kimage_free_extra_pages(struct kimage *image) |
| 571 | { |
| 572 | /* Walk through and free any extra destination pages I may have */ |
| 573 | kimage_free_page_list(&image->dest_pages); |
| 574 | |
| 575 | /* Walk through and free any unuseable pages I have cached */ |
| 576 | kimage_free_page_list(&image->unuseable_pages); |
| 577 | |
| 578 | } |
| 579 | static int kimage_terminate(struct kimage *image) |
| 580 | { |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 581 | if (*image->entry != 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 582 | image->entry++; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 583 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 584 | *image->entry = IND_DONE; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 585 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 586 | return 0; |
| 587 | } |
| 588 | |
| 589 | #define for_each_kimage_entry(image, ptr, entry) \ |
| 590 | for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \ |
| 591 | ptr = (entry & IND_INDIRECTION)? \ |
| 592 | phys_to_virt((entry & PAGE_MASK)): ptr +1) |
| 593 | |
| 594 | static void kimage_free_entry(kimage_entry_t entry) |
| 595 | { |
| 596 | struct page *page; |
| 597 | |
| 598 | page = pfn_to_page(entry >> PAGE_SHIFT); |
| 599 | kimage_free_pages(page); |
| 600 | } |
| 601 | |
| 602 | static void kimage_free(struct kimage *image) |
| 603 | { |
| 604 | kimage_entry_t *ptr, entry; |
| 605 | kimage_entry_t ind = 0; |
| 606 | |
| 607 | if (!image) |
| 608 | return; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 609 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 610 | kimage_free_extra_pages(image); |
| 611 | for_each_kimage_entry(image, ptr, entry) { |
| 612 | if (entry & IND_INDIRECTION) { |
| 613 | /* Free the previous indirection page */ |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 614 | if (ind & IND_INDIRECTION) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 615 | kimage_free_entry(ind); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 616 | /* Save this indirection page until we are |
| 617 | * done with it. |
| 618 | */ |
| 619 | ind = entry; |
| 620 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 621 | else if (entry & IND_SOURCE) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 622 | kimage_free_entry(entry); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 623 | } |
| 624 | /* Free the final indirection page */ |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 625 | if (ind & IND_INDIRECTION) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 626 | kimage_free_entry(ind); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 627 | |
| 628 | /* Handle any machine specific cleanup */ |
| 629 | machine_kexec_cleanup(image); |
| 630 | |
| 631 | /* Free the kexec control pages... */ |
| 632 | kimage_free_page_list(&image->control_pages); |
| 633 | kfree(image); |
| 634 | } |
| 635 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 636 | static kimage_entry_t *kimage_dst_used(struct kimage *image, |
| 637 | unsigned long page) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 638 | { |
| 639 | kimage_entry_t *ptr, entry; |
| 640 | unsigned long destination = 0; |
| 641 | |
| 642 | for_each_kimage_entry(image, ptr, entry) { |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 643 | if (entry & IND_DESTINATION) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 644 | destination = entry & PAGE_MASK; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 645 | else if (entry & IND_SOURCE) { |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 646 | if (page == destination) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 647 | return ptr; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 648 | destination += PAGE_SIZE; |
| 649 | } |
| 650 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 651 | |
Alexey Dobriyan | 314b6a4 | 2005-06-27 22:29:33 -0700 | [diff] [blame] | 652 | return NULL; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 653 | } |
| 654 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 655 | static struct page *kimage_alloc_page(struct kimage *image, |
Al Viro | 9796fdd | 2005-10-21 03:22:03 -0400 | [diff] [blame] | 656 | gfp_t gfp_mask, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 657 | unsigned long destination) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 658 | { |
| 659 | /* |
| 660 | * Here we implement safeguards to ensure that a source page |
| 661 | * is not copied to its destination page before the data on |
| 662 | * the destination page is no longer useful. |
| 663 | * |
| 664 | * To do this we maintain the invariant that a source page is |
| 665 | * either its own destination page, or it is not a |
| 666 | * destination page at all. |
| 667 | * |
| 668 | * That is slightly stronger than required, but the proof |
| 669 | * that no problems will not occur is trivial, and the |
| 670 | * implementation is simply to verify. |
| 671 | * |
| 672 | * When allocating all pages normally this algorithm will run |
| 673 | * in O(N) time, but in the worst case it will run in O(N^2) |
| 674 | * time. If the runtime is a problem the data structures can |
| 675 | * be fixed. |
| 676 | */ |
| 677 | struct page *page; |
| 678 | unsigned long addr; |
| 679 | |
| 680 | /* |
| 681 | * Walk through the list of destination pages, and see if I |
| 682 | * have a match. |
| 683 | */ |
| 684 | list_for_each_entry(page, &image->dest_pages, lru) { |
| 685 | addr = page_to_pfn(page) << PAGE_SHIFT; |
| 686 | if (addr == destination) { |
| 687 | list_del(&page->lru); |
| 688 | return page; |
| 689 | } |
| 690 | } |
| 691 | page = NULL; |
| 692 | while (1) { |
| 693 | kimage_entry_t *old; |
| 694 | |
| 695 | /* Allocate a page, if we run out of memory give up */ |
| 696 | page = kimage_alloc_pages(gfp_mask, 0); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 697 | if (!page) |
Alexey Dobriyan | 314b6a4 | 2005-06-27 22:29:33 -0700 | [diff] [blame] | 698 | return NULL; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 699 | /* If the page cannot be used file it away */ |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 700 | if (page_to_pfn(page) > |
| 701 | (KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 702 | list_add(&page->lru, &image->unuseable_pages); |
| 703 | continue; |
| 704 | } |
| 705 | addr = page_to_pfn(page) << PAGE_SHIFT; |
| 706 | |
| 707 | /* If it is the destination page we want use it */ |
| 708 | if (addr == destination) |
| 709 | break; |
| 710 | |
| 711 | /* If the page is not a destination page use it */ |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 712 | if (!kimage_is_destination_range(image, addr, |
| 713 | addr + PAGE_SIZE)) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 714 | break; |
| 715 | |
| 716 | /* |
| 717 | * I know that the page is someones destination page. |
| 718 | * See if there is already a source page for this |
| 719 | * destination page. And if so swap the source pages. |
| 720 | */ |
| 721 | old = kimage_dst_used(image, addr); |
| 722 | if (old) { |
| 723 | /* If so move it */ |
| 724 | unsigned long old_addr; |
| 725 | struct page *old_page; |
| 726 | |
| 727 | old_addr = *old & PAGE_MASK; |
| 728 | old_page = pfn_to_page(old_addr >> PAGE_SHIFT); |
| 729 | copy_highpage(page, old_page); |
| 730 | *old = addr | (*old & ~PAGE_MASK); |
| 731 | |
| 732 | /* The old page I have found cannot be a |
| 733 | * destination page, so return it. |
| 734 | */ |
| 735 | addr = old_addr; |
| 736 | page = old_page; |
| 737 | break; |
| 738 | } |
| 739 | else { |
| 740 | /* Place the page on the destination list I |
| 741 | * will use it later. |
| 742 | */ |
| 743 | list_add(&page->lru, &image->dest_pages); |
| 744 | } |
| 745 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 746 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 747 | return page; |
| 748 | } |
| 749 | |
| 750 | static int kimage_load_normal_segment(struct kimage *image, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 751 | struct kexec_segment *segment) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 752 | { |
| 753 | unsigned long maddr; |
| 754 | unsigned long ubytes, mbytes; |
| 755 | int result; |
Alexey Dobriyan | 314b6a4 | 2005-06-27 22:29:33 -0700 | [diff] [blame] | 756 | unsigned char __user *buf; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 757 | |
| 758 | result = 0; |
| 759 | buf = segment->buf; |
| 760 | ubytes = segment->bufsz; |
| 761 | mbytes = segment->memsz; |
| 762 | maddr = segment->mem; |
| 763 | |
| 764 | result = kimage_set_destination(image, maddr); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 765 | if (result < 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 766 | goto out; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 767 | |
| 768 | while (mbytes) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 769 | struct page *page; |
| 770 | char *ptr; |
| 771 | size_t uchunk, mchunk; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 772 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 773 | page = kimage_alloc_page(image, GFP_HIGHUSER, maddr); |
| 774 | if (page == 0) { |
| 775 | result = -ENOMEM; |
| 776 | goto out; |
| 777 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 778 | result = kimage_add_page(image, page_to_pfn(page) |
| 779 | << PAGE_SHIFT); |
| 780 | if (result < 0) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 781 | goto out; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 782 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 783 | ptr = kmap(page); |
| 784 | /* Start with a clear page */ |
| 785 | memset(ptr, 0, PAGE_SIZE); |
| 786 | ptr += maddr & ~PAGE_MASK; |
| 787 | mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 788 | if (mchunk > mbytes) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 789 | mchunk = mbytes; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 790 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 791 | uchunk = mchunk; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 792 | if (uchunk > ubytes) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 793 | uchunk = ubytes; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 794 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 795 | result = copy_from_user(ptr, buf, uchunk); |
| 796 | kunmap(page); |
| 797 | if (result) { |
| 798 | result = (result < 0) ? result : -EIO; |
| 799 | goto out; |
| 800 | } |
| 801 | ubytes -= uchunk; |
| 802 | maddr += mchunk; |
| 803 | buf += mchunk; |
| 804 | mbytes -= mchunk; |
| 805 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 806 | out: |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 807 | return result; |
| 808 | } |
| 809 | |
| 810 | static int kimage_load_crash_segment(struct kimage *image, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 811 | struct kexec_segment *segment) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 812 | { |
| 813 | /* For crash dumps kernels we simply copy the data from |
| 814 | * user space to it's destination. |
| 815 | * We do things a page at a time for the sake of kmap. |
| 816 | */ |
| 817 | unsigned long maddr; |
| 818 | unsigned long ubytes, mbytes; |
| 819 | int result; |
Alexey Dobriyan | 314b6a4 | 2005-06-27 22:29:33 -0700 | [diff] [blame] | 820 | unsigned char __user *buf; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 821 | |
| 822 | result = 0; |
| 823 | buf = segment->buf; |
| 824 | ubytes = segment->bufsz; |
| 825 | mbytes = segment->memsz; |
| 826 | maddr = segment->mem; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 827 | while (mbytes) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 828 | struct page *page; |
| 829 | char *ptr; |
| 830 | size_t uchunk, mchunk; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 831 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 832 | page = pfn_to_page(maddr >> PAGE_SHIFT); |
| 833 | if (page == 0) { |
| 834 | result = -ENOMEM; |
| 835 | goto out; |
| 836 | } |
| 837 | ptr = kmap(page); |
| 838 | ptr += maddr & ~PAGE_MASK; |
| 839 | mchunk = PAGE_SIZE - (maddr & ~PAGE_MASK); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 840 | if (mchunk > mbytes) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 841 | mchunk = mbytes; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 842 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 843 | uchunk = mchunk; |
| 844 | if (uchunk > ubytes) { |
| 845 | uchunk = ubytes; |
| 846 | /* Zero the trailing part of the page */ |
| 847 | memset(ptr + uchunk, 0, mchunk - uchunk); |
| 848 | } |
| 849 | result = copy_from_user(ptr, buf, uchunk); |
| 850 | kunmap(page); |
| 851 | if (result) { |
| 852 | result = (result < 0) ? result : -EIO; |
| 853 | goto out; |
| 854 | } |
| 855 | ubytes -= uchunk; |
| 856 | maddr += mchunk; |
| 857 | buf += mchunk; |
| 858 | mbytes -= mchunk; |
| 859 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 860 | out: |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 861 | return result; |
| 862 | } |
| 863 | |
| 864 | static int kimage_load_segment(struct kimage *image, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 865 | struct kexec_segment *segment) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 866 | { |
| 867 | int result = -ENOMEM; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 868 | |
| 869 | switch (image->type) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 870 | case KEXEC_TYPE_DEFAULT: |
| 871 | result = kimage_load_normal_segment(image, segment); |
| 872 | break; |
| 873 | case KEXEC_TYPE_CRASH: |
| 874 | result = kimage_load_crash_segment(image, segment); |
| 875 | break; |
| 876 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 877 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 878 | return result; |
| 879 | } |
| 880 | |
| 881 | /* |
| 882 | * Exec Kernel system call: for obvious reasons only root may call it. |
| 883 | * |
| 884 | * This call breaks up into three pieces. |
| 885 | * - A generic part which loads the new kernel from the current |
| 886 | * address space, and very carefully places the data in the |
| 887 | * allocated pages. |
| 888 | * |
| 889 | * - A generic part that interacts with the kernel and tells all of |
| 890 | * the devices to shut down. Preventing on-going dmas, and placing |
| 891 | * the devices in a consistent state so a later kernel can |
| 892 | * reinitialize them. |
| 893 | * |
| 894 | * - A machine specific part that includes the syscall number |
| 895 | * and the copies the image to it's final destination. And |
| 896 | * jumps into the image at entry. |
| 897 | * |
| 898 | * kexec does not sync, or unmount filesystems so if you need |
| 899 | * that to happen you need to do that yourself. |
| 900 | */ |
| 901 | struct kimage *kexec_image = NULL; |
| 902 | static struct kimage *kexec_crash_image = NULL; |
| 903 | /* |
| 904 | * A home grown binary mutex. |
| 905 | * Nothing can wait so this mutex is safe to use |
| 906 | * in interrupt context :) |
| 907 | */ |
| 908 | static int kexec_lock = 0; |
| 909 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 910 | asmlinkage long sys_kexec_load(unsigned long entry, unsigned long nr_segments, |
| 911 | struct kexec_segment __user *segments, |
| 912 | unsigned long flags) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 913 | { |
| 914 | struct kimage **dest_image, *image; |
| 915 | int locked; |
| 916 | int result; |
| 917 | |
| 918 | /* We only trust the superuser with rebooting the system. */ |
| 919 | if (!capable(CAP_SYS_BOOT)) |
| 920 | return -EPERM; |
| 921 | |
| 922 | /* |
| 923 | * Verify we have a legal set of flags |
| 924 | * This leaves us room for future extensions. |
| 925 | */ |
| 926 | if ((flags & KEXEC_FLAGS) != (flags & ~KEXEC_ARCH_MASK)) |
| 927 | return -EINVAL; |
| 928 | |
| 929 | /* Verify we are on the appropriate architecture */ |
| 930 | if (((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH) && |
| 931 | ((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT)) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 932 | return -EINVAL; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 933 | |
| 934 | /* Put an artificial cap on the number |
| 935 | * of segments passed to kexec_load. |
| 936 | */ |
| 937 | if (nr_segments > KEXEC_SEGMENT_MAX) |
| 938 | return -EINVAL; |
| 939 | |
| 940 | image = NULL; |
| 941 | result = 0; |
| 942 | |
| 943 | /* Because we write directly to the reserved memory |
| 944 | * region when loading crash kernels we need a mutex here to |
| 945 | * prevent multiple crash kernels from attempting to load |
| 946 | * simultaneously, and to prevent a crash kernel from loading |
| 947 | * over the top of a in use crash kernel. |
| 948 | * |
| 949 | * KISS: always take the mutex. |
| 950 | */ |
| 951 | locked = xchg(&kexec_lock, 1); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 952 | if (locked) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 953 | return -EBUSY; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 954 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 955 | dest_image = &kexec_image; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 956 | if (flags & KEXEC_ON_CRASH) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 957 | dest_image = &kexec_crash_image; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 958 | if (nr_segments > 0) { |
| 959 | unsigned long i; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 960 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 961 | /* Loading another kernel to reboot into */ |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 962 | if ((flags & KEXEC_ON_CRASH) == 0) |
| 963 | result = kimage_normal_alloc(&image, entry, |
| 964 | nr_segments, segments); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 965 | /* Loading another kernel to switch to if this one crashes */ |
| 966 | else if (flags & KEXEC_ON_CRASH) { |
| 967 | /* Free any current crash dump kernel before |
| 968 | * we corrupt it. |
| 969 | */ |
| 970 | kimage_free(xchg(&kexec_crash_image, NULL)); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 971 | result = kimage_crash_alloc(&image, entry, |
| 972 | nr_segments, segments); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 973 | } |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 974 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 975 | goto out; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 976 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 977 | result = machine_kexec_prepare(image); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 978 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 979 | goto out; |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 980 | |
| 981 | for (i = 0; i < nr_segments; i++) { |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 982 | result = kimage_load_segment(image, &image->segment[i]); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 983 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 984 | goto out; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 985 | } |
| 986 | result = kimage_terminate(image); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 987 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 988 | goto out; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 989 | } |
| 990 | /* Install the new kernel, and Uninstall the old */ |
| 991 | image = xchg(dest_image, image); |
| 992 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 993 | out: |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 994 | xchg(&kexec_lock, 0); /* Release the mutex */ |
| 995 | kimage_free(image); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 996 | |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 997 | return result; |
| 998 | } |
| 999 | |
| 1000 | #ifdef CONFIG_COMPAT |
| 1001 | asmlinkage long compat_sys_kexec_load(unsigned long entry, |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 1002 | unsigned long nr_segments, |
| 1003 | struct compat_kexec_segment __user *segments, |
| 1004 | unsigned long flags) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1005 | { |
| 1006 | struct compat_kexec_segment in; |
| 1007 | struct kexec_segment out, __user *ksegments; |
| 1008 | unsigned long i, result; |
| 1009 | |
| 1010 | /* Don't allow clients that don't understand the native |
| 1011 | * architecture to do anything. |
| 1012 | */ |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 1013 | if ((flags & KEXEC_ARCH_MASK) == KEXEC_ARCH_DEFAULT) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1014 | return -EINVAL; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1015 | |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 1016 | if (nr_segments > KEXEC_SEGMENT_MAX) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1017 | return -EINVAL; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1018 | |
| 1019 | ksegments = compat_alloc_user_space(nr_segments * sizeof(out)); |
| 1020 | for (i=0; i < nr_segments; i++) { |
| 1021 | result = copy_from_user(&in, &segments[i], sizeof(in)); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 1022 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1023 | return -EFAULT; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1024 | |
| 1025 | out.buf = compat_ptr(in.buf); |
| 1026 | out.bufsz = in.bufsz; |
| 1027 | out.mem = in.mem; |
| 1028 | out.memsz = in.memsz; |
| 1029 | |
| 1030 | result = copy_to_user(&ksegments[i], &out, sizeof(out)); |
Maneesh Soni | 72414d3 | 2005-06-25 14:58:28 -0700 | [diff] [blame] | 1031 | if (result) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1032 | return -EFAULT; |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1033 | } |
| 1034 | |
| 1035 | return sys_kexec_load(entry, nr_segments, ksegments, flags); |
| 1036 | } |
| 1037 | #endif |
| 1038 | |
Alexander Nyberg | 6e274d1 | 2005-06-25 14:58:26 -0700 | [diff] [blame] | 1039 | void crash_kexec(struct pt_regs *regs) |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1040 | { |
| 1041 | struct kimage *image; |
| 1042 | int locked; |
| 1043 | |
| 1044 | |
| 1045 | /* Take the kexec_lock here to prevent sys_kexec_load |
| 1046 | * running on one cpu from replacing the crash kernel |
| 1047 | * we are using after a panic on a different cpu. |
| 1048 | * |
| 1049 | * If the crash kernel was not located in a fixed area |
| 1050 | * of memory the xchg(&kexec_crash_image) would be |
| 1051 | * sufficient. But since I reuse the memory... |
| 1052 | */ |
| 1053 | locked = xchg(&kexec_lock, 1); |
| 1054 | if (!locked) { |
| 1055 | image = xchg(&kexec_crash_image, NULL); |
| 1056 | if (image) { |
Alexander Nyberg | 6e274d1 | 2005-06-25 14:58:26 -0700 | [diff] [blame] | 1057 | machine_crash_shutdown(regs); |
Eric W. Biederman | dc009d9 | 2005-06-25 14:57:52 -0700 | [diff] [blame] | 1058 | machine_kexec(image); |
| 1059 | } |
| 1060 | xchg(&kexec_lock, 0); |
| 1061 | } |
| 1062 | } |