1 /* 2 * ipmi_watchdog.c 3 * 4 * A watchdog timer based upon the IPMI interface. 5 * 6 * Author: MontaVista Software, Inc. 7 * Corey Minyard <minyard@mvista.com> 8 * source@mvista.com 9 * 10 * Copyright 2002 MontaVista Software Inc. 11 * 12 * This program is free software; you can redistribute it and/or modify it 13 * under the terms of the GNU General Public License as published by the 14 * Free Software Foundation; either version 2 of the License, or (at your 15 * option) any later version. 16 * 17 * 18 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 19 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 23 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 24 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 25 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR 26 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE 27 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * You should have received a copy of the GNU General Public License along 30 * with this program; if not, write to the Free Software Foundation, Inc., 31 * 675 Mass Ave, Cambridge, MA 02139, USA. 32 */ 33 34 #include <linux/module.h> 35 #include <linux/moduleparam.h> 36 #include <linux/ipmi.h> 37 #include <linux/ipmi_smi.h> 38 #include <linux/mutex.h> 39 #include <linux/watchdog.h> 40 #include <linux/miscdevice.h> 41 #include <linux/init.h> 42 #include <linux/completion.h> 43 #include <linux/kdebug.h> 44 #include <linux/rwsem.h> 45 #include <linux/errno.h> 46 #include <asm/uaccess.h> 47 #include <linux/notifier.h> 48 #include <linux/nmi.h> 49 #include <linux/reboot.h> 50 #include <linux/wait.h> 51 #include <linux/poll.h> 52 #include <linux/string.h> 53 #include <linux/ctype.h> 54 #include <linux/delay.h> 55 #include <linux/atomic.h> 56 57 #ifdef CONFIG_X86 58 /* 59 * This is ugly, but I've determined that x86 is the only architecture 60 * that can reasonably support the IPMI NMI watchdog timeout at this 61 * time. If another architecture adds this capability somehow, it 62 * will have to be a somewhat different mechanism and I have no idea 63 * how it will work. So in the unlikely event that another 64 * architecture supports this, we can figure out a good generic 65 * mechanism for it at that time. 66 */ 67 #include <asm/kdebug.h> 68 #include <asm/nmi.h> 69 #define HAVE_DIE_NMI 70 #endif 71 72 #define PFX "IPMI Watchdog: " 73 74 /* 75 * The IPMI command/response information for the watchdog timer. 76 */ 77 78 /* values for byte 1 of the set command, byte 2 of the get response. */ 79 #define WDOG_DONT_LOG (1 << 7) 80 #define WDOG_DONT_STOP_ON_SET (1 << 6) 81 #define WDOG_SET_TIMER_USE(byte, use) \ 82 byte = ((byte) & 0xf8) | ((use) & 0x7) 83 #define WDOG_GET_TIMER_USE(byte) ((byte) & 0x7) 84 #define WDOG_TIMER_USE_BIOS_FRB2 1 85 #define WDOG_TIMER_USE_BIOS_POST 2 86 #define WDOG_TIMER_USE_OS_LOAD 3 87 #define WDOG_TIMER_USE_SMS_OS 4 88 #define WDOG_TIMER_USE_OEM 5 89 90 /* values for byte 2 of the set command, byte 3 of the get response. */ 91 #define WDOG_SET_PRETIMEOUT_ACT(byte, use) \ 92 byte = ((byte) & 0x8f) | (((use) & 0x7) << 4) 93 #define WDOG_GET_PRETIMEOUT_ACT(byte) (((byte) >> 4) & 0x7) 94 #define WDOG_PRETIMEOUT_NONE 0 95 #define WDOG_PRETIMEOUT_SMI 1 96 #define WDOG_PRETIMEOUT_NMI 2 97 #define WDOG_PRETIMEOUT_MSG_INT 3 98 99 /* Operations that can be performed on a pretimout. */ 100 #define WDOG_PREOP_NONE 0 101 #define WDOG_PREOP_PANIC 1 102 /* Cause data to be available to read. Doesn't work in NMI mode. */ 103 #define WDOG_PREOP_GIVE_DATA 2 104 105 /* Actions to perform on a full timeout. */ 106 #define WDOG_SET_TIMEOUT_ACT(byte, use) \ 107 byte = ((byte) & 0xf8) | ((use) & 0x7) 108 #define WDOG_GET_TIMEOUT_ACT(byte) ((byte) & 0x7) 109 #define WDOG_TIMEOUT_NONE 0 110 #define WDOG_TIMEOUT_RESET 1 111 #define WDOG_TIMEOUT_POWER_DOWN 2 112 #define WDOG_TIMEOUT_POWER_CYCLE 3 113 114 /* 115 * Byte 3 of the get command, byte 4 of the get response is the 116 * pre-timeout in seconds. 117 */ 118 119 /* Bits for setting byte 4 of the set command, byte 5 of the get response. */ 120 #define WDOG_EXPIRE_CLEAR_BIOS_FRB2 (1 << 1) 121 #define WDOG_EXPIRE_CLEAR_BIOS_POST (1 << 2) 122 #define WDOG_EXPIRE_CLEAR_OS_LOAD (1 << 3) 123 #define WDOG_EXPIRE_CLEAR_SMS_OS (1 << 4) 124 #define WDOG_EXPIRE_CLEAR_OEM (1 << 5) 125 126 /* 127 * Setting/getting the watchdog timer value. This is for bytes 5 and 128 * 6 (the timeout time) of the set command, and bytes 6 and 7 (the 129 * timeout time) and 8 and 9 (the current countdown value) of the 130 * response. The timeout value is given in seconds (in the command it 131 * is 100ms intervals). 132 */ 133 #define WDOG_SET_TIMEOUT(byte1, byte2, val) \ 134 (byte1) = (((val) * 10) & 0xff), (byte2) = (((val) * 10) >> 8) 135 #define WDOG_GET_TIMEOUT(byte1, byte2) \ 136 (((byte1) | ((byte2) << 8)) / 10) 137 138 #define IPMI_WDOG_RESET_TIMER 0x22 139 #define IPMI_WDOG_SET_TIMER 0x24 140 #define IPMI_WDOG_GET_TIMER 0x25 141 142 #define IPMI_WDOG_TIMER_NOT_INIT_RESP 0x80 143 144 static DEFINE_MUTEX(ipmi_watchdog_mutex); 145 static bool nowayout = WATCHDOG_NOWAYOUT; 146 147 static ipmi_user_t watchdog_user; 148 static int watchdog_ifnum; 149 150 /* Default the timeout to 10 seconds. */ 151 static int timeout = 10; 152 153 /* The pre-timeout is disabled by default. */ 154 static int pretimeout; 155 156 /* Default timeout to set on panic */ 157 static int panic_wdt_timeout = 255; 158 159 /* Default action is to reset the board on a timeout. */ 160 static unsigned char action_val = WDOG_TIMEOUT_RESET; 161 162 static char action[16] = "reset"; 163 164 static unsigned char preaction_val = WDOG_PRETIMEOUT_NONE; 165 166 static char preaction[16] = "pre_none"; 167 168 static unsigned char preop_val = WDOG_PREOP_NONE; 169 170 static char preop[16] = "preop_none"; 171 static DEFINE_SPINLOCK(ipmi_read_lock); 172 static char data_to_read; 173 static DECLARE_WAIT_QUEUE_HEAD(read_q); 174 static struct fasync_struct *fasync_q; 175 static char pretimeout_since_last_heartbeat; 176 static char expect_close; 177 178 static int ifnum_to_use = -1; 179 180 /* Parameters to ipmi_set_timeout */ 181 #define IPMI_SET_TIMEOUT_NO_HB 0 182 #define IPMI_SET_TIMEOUT_HB_IF_NECESSARY 1 183 #define IPMI_SET_TIMEOUT_FORCE_HB 2 184 185 static int ipmi_set_timeout(int do_heartbeat); 186 static void ipmi_register_watchdog(int ipmi_intf); 187 static void ipmi_unregister_watchdog(int ipmi_intf); 188 189 /* 190 * If true, the driver will start running as soon as it is configured 191 * and ready. 192 */ 193 static int start_now; 194 195 static int set_param_timeout(const char *val, const struct kernel_param *kp) 196 { 197 char *endp; 198 int l; 199 int rv = 0; 200 201 if (!val) 202 return -EINVAL; 203 l = simple_strtoul(val, &endp, 0); 204 if (endp == val) 205 return -EINVAL; 206 207 *((int *)kp->arg) = l; 208 if (watchdog_user) 209 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 210 211 return rv; 212 } 213 214 static const struct kernel_param_ops param_ops_timeout = { 215 .set = set_param_timeout, 216 .get = param_get_int, 217 }; 218 #define param_check_timeout param_check_int 219 220 typedef int (*action_fn)(const char *intval, char *outval); 221 222 static int action_op(const char *inval, char *outval); 223 static int preaction_op(const char *inval, char *outval); 224 static int preop_op(const char *inval, char *outval); 225 static void check_parms(void); 226 227 static int set_param_str(const char *val, const struct kernel_param *kp) 228 { 229 action_fn fn = (action_fn) kp->arg; 230 int rv = 0; 231 char valcp[16]; 232 char *s; 233 234 strncpy(valcp, val, 16); 235 valcp[15] = '\0'; 236 237 s = strstrip(valcp); 238 239 rv = fn(s, NULL); 240 if (rv) 241 goto out; 242 243 check_parms(); 244 if (watchdog_user) 245 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 246 247 out: 248 return rv; 249 } 250 251 static int get_param_str(char *buffer, const struct kernel_param *kp) 252 { 253 action_fn fn = (action_fn) kp->arg; 254 int rv; 255 256 rv = fn(NULL, buffer); 257 if (rv) 258 return rv; 259 return strlen(buffer); 260 } 261 262 263 static int set_param_wdog_ifnum(const char *val, const struct kernel_param *kp) 264 { 265 int rv = param_set_int(val, kp); 266 if (rv) 267 return rv; 268 if ((ifnum_to_use < 0) || (ifnum_to_use == watchdog_ifnum)) 269 return 0; 270 271 ipmi_unregister_watchdog(watchdog_ifnum); 272 ipmi_register_watchdog(ifnum_to_use); 273 return 0; 274 } 275 276 static const struct kernel_param_ops param_ops_wdog_ifnum = { 277 .set = set_param_wdog_ifnum, 278 .get = param_get_int, 279 }; 280 281 #define param_check_wdog_ifnum param_check_int 282 283 static const struct kernel_param_ops param_ops_str = { 284 .set = set_param_str, 285 .get = get_param_str, 286 }; 287 288 module_param(ifnum_to_use, wdog_ifnum, 0644); 289 MODULE_PARM_DESC(ifnum_to_use, "The interface number to use for the watchdog " 290 "timer. Setting to -1 defaults to the first registered " 291 "interface"); 292 293 module_param(timeout, timeout, 0644); 294 MODULE_PARM_DESC(timeout, "Timeout value in seconds."); 295 296 module_param(pretimeout, timeout, 0644); 297 MODULE_PARM_DESC(pretimeout, "Pretimeout value in seconds."); 298 299 module_param(panic_wdt_timeout, timeout, 0644); 300 MODULE_PARM_DESC(timeout, "Timeout value on kernel panic in seconds."); 301 302 module_param_cb(action, ¶m_ops_str, action_op, 0644); 303 MODULE_PARM_DESC(action, "Timeout action. One of: " 304 "reset, none, power_cycle, power_off."); 305 306 module_param_cb(preaction, ¶m_ops_str, preaction_op, 0644); 307 MODULE_PARM_DESC(preaction, "Pretimeout action. One of: " 308 "pre_none, pre_smi, pre_nmi, pre_int."); 309 310 module_param_cb(preop, ¶m_ops_str, preop_op, 0644); 311 MODULE_PARM_DESC(preop, "Pretimeout driver operation. One of: " 312 "preop_none, preop_panic, preop_give_data."); 313 314 module_param(start_now, int, 0444); 315 MODULE_PARM_DESC(start_now, "Set to 1 to start the watchdog as" 316 "soon as the driver is loaded."); 317 318 module_param(nowayout, bool, 0644); 319 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " 320 "(default=CONFIG_WATCHDOG_NOWAYOUT)"); 321 322 /* Default state of the timer. */ 323 static unsigned char ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 324 325 /* If shutting down via IPMI, we ignore the heartbeat. */ 326 static int ipmi_ignore_heartbeat; 327 328 /* Is someone using the watchdog? Only one user is allowed. */ 329 static unsigned long ipmi_wdog_open; 330 331 /* 332 * If set to 1, the heartbeat command will set the state to reset and 333 * start the timer. The timer doesn't normally run when the driver is 334 * first opened until the heartbeat is set the first time, this 335 * variable is used to accomplish this. 336 */ 337 static int ipmi_start_timer_on_heartbeat; 338 339 /* IPMI version of the BMC. */ 340 static unsigned char ipmi_version_major; 341 static unsigned char ipmi_version_minor; 342 343 /* If a pretimeout occurs, this is used to allow only one panic to happen. */ 344 static atomic_t preop_panic_excl = ATOMIC_INIT(-1); 345 346 #ifdef HAVE_DIE_NMI 347 static int testing_nmi; 348 static int nmi_handler_registered; 349 #endif 350 351 static int ipmi_heartbeat(void); 352 353 /* 354 * We use a mutex to make sure that only one thing can send a set 355 * timeout at one time, because we only have one copy of the data. 356 * The mutex is claimed when the set_timeout is sent and freed 357 * when both messages are free. 358 */ 359 static atomic_t set_timeout_tofree = ATOMIC_INIT(0); 360 static DEFINE_MUTEX(set_timeout_lock); 361 static DECLARE_COMPLETION(set_timeout_wait); 362 static void set_timeout_free_smi(struct ipmi_smi_msg *msg) 363 { 364 if (atomic_dec_and_test(&set_timeout_tofree)) 365 complete(&set_timeout_wait); 366 } 367 static void set_timeout_free_recv(struct ipmi_recv_msg *msg) 368 { 369 if (atomic_dec_and_test(&set_timeout_tofree)) 370 complete(&set_timeout_wait); 371 } 372 static struct ipmi_smi_msg set_timeout_smi_msg = { 373 .done = set_timeout_free_smi 374 }; 375 static struct ipmi_recv_msg set_timeout_recv_msg = { 376 .done = set_timeout_free_recv 377 }; 378 379 static int i_ipmi_set_timeout(struct ipmi_smi_msg *smi_msg, 380 struct ipmi_recv_msg *recv_msg, 381 int *send_heartbeat_now) 382 { 383 struct kernel_ipmi_msg msg; 384 unsigned char data[6]; 385 int rv; 386 struct ipmi_system_interface_addr addr; 387 int hbnow = 0; 388 389 390 /* These can be cleared as we are setting the timeout. */ 391 pretimeout_since_last_heartbeat = 0; 392 393 data[0] = 0; 394 WDOG_SET_TIMER_USE(data[0], WDOG_TIMER_USE_SMS_OS); 395 396 if ((ipmi_version_major > 1) 397 || ((ipmi_version_major == 1) && (ipmi_version_minor >= 5))) { 398 /* This is an IPMI 1.5-only feature. */ 399 data[0] |= WDOG_DONT_STOP_ON_SET; 400 } else if (ipmi_watchdog_state != WDOG_TIMEOUT_NONE) { 401 /* 402 * In ipmi 1.0, setting the timer stops the watchdog, we 403 * need to start it back up again. 404 */ 405 hbnow = 1; 406 } 407 408 data[1] = 0; 409 WDOG_SET_TIMEOUT_ACT(data[1], ipmi_watchdog_state); 410 if ((pretimeout > 0) && (ipmi_watchdog_state != WDOG_TIMEOUT_NONE)) { 411 WDOG_SET_PRETIMEOUT_ACT(data[1], preaction_val); 412 data[2] = pretimeout; 413 } else { 414 WDOG_SET_PRETIMEOUT_ACT(data[1], WDOG_PRETIMEOUT_NONE); 415 data[2] = 0; /* No pretimeout. */ 416 } 417 data[3] = 0; 418 WDOG_SET_TIMEOUT(data[4], data[5], timeout); 419 420 addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE; 421 addr.channel = IPMI_BMC_CHANNEL; 422 addr.lun = 0; 423 424 msg.netfn = 0x06; 425 msg.cmd = IPMI_WDOG_SET_TIMER; 426 msg.data = data; 427 msg.data_len = sizeof(data); 428 rv = ipmi_request_supply_msgs(watchdog_user, 429 (struct ipmi_addr *) &addr, 430 0, 431 &msg, 432 NULL, 433 smi_msg, 434 recv_msg, 435 1); 436 if (rv) { 437 printk(KERN_WARNING PFX "set timeout error: %d\n", 438 rv); 439 } 440 441 if (send_heartbeat_now) 442 *send_heartbeat_now = hbnow; 443 444 return rv; 445 } 446 447 static int ipmi_set_timeout(int do_heartbeat) 448 { 449 int send_heartbeat_now; 450 int rv; 451 452 453 /* We can only send one of these at a time. */ 454 mutex_lock(&set_timeout_lock); 455 456 atomic_set(&set_timeout_tofree, 2); 457 458 rv = i_ipmi_set_timeout(&set_timeout_smi_msg, 459 &set_timeout_recv_msg, 460 &send_heartbeat_now); 461 if (rv) { 462 mutex_unlock(&set_timeout_lock); 463 goto out; 464 } 465 466 wait_for_completion(&set_timeout_wait); 467 468 mutex_unlock(&set_timeout_lock); 469 470 if ((do_heartbeat == IPMI_SET_TIMEOUT_FORCE_HB) 471 || ((send_heartbeat_now) 472 && (do_heartbeat == IPMI_SET_TIMEOUT_HB_IF_NECESSARY))) 473 rv = ipmi_heartbeat(); 474 475 out: 476 return rv; 477 } 478 479 static atomic_t panic_done_count = ATOMIC_INIT(0); 480 481 static void panic_smi_free(struct ipmi_smi_msg *msg) 482 { 483 atomic_dec(&panic_done_count); 484 } 485 static void panic_recv_free(struct ipmi_recv_msg *msg) 486 { 487 atomic_dec(&panic_done_count); 488 } 489 490 static struct ipmi_smi_msg panic_halt_heartbeat_smi_msg = { 491 .done = panic_smi_free 492 }; 493 static struct ipmi_recv_msg panic_halt_heartbeat_recv_msg = { 494 .done = panic_recv_free 495 }; 496 497 static void panic_halt_ipmi_heartbeat(void) 498 { 499 struct kernel_ipmi_msg msg; 500 struct ipmi_system_interface_addr addr; 501 int rv; 502 503 /* 504 * Don't reset the timer if we have the timer turned off, that 505 * re-enables the watchdog. 506 */ 507 if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) 508 return; 509 510 addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE; 511 addr.channel = IPMI_BMC_CHANNEL; 512 addr.lun = 0; 513 514 msg.netfn = 0x06; 515 msg.cmd = IPMI_WDOG_RESET_TIMER; 516 msg.data = NULL; 517 msg.data_len = 0; 518 atomic_add(2, &panic_done_count); 519 rv = ipmi_request_supply_msgs(watchdog_user, 520 (struct ipmi_addr *) &addr, 521 0, 522 &msg, 523 NULL, 524 &panic_halt_heartbeat_smi_msg, 525 &panic_halt_heartbeat_recv_msg, 526 1); 527 if (rv) 528 atomic_sub(2, &panic_done_count); 529 } 530 531 static struct ipmi_smi_msg panic_halt_smi_msg = { 532 .done = panic_smi_free 533 }; 534 static struct ipmi_recv_msg panic_halt_recv_msg = { 535 .done = panic_recv_free 536 }; 537 538 /* 539 * Special call, doesn't claim any locks. This is only to be called 540 * at panic or halt time, in run-to-completion mode, when the caller 541 * is the only CPU and the only thing that will be going is these IPMI 542 * calls. 543 */ 544 static void panic_halt_ipmi_set_timeout(void) 545 { 546 int send_heartbeat_now; 547 int rv; 548 549 /* Wait for the messages to be free. */ 550 while (atomic_read(&panic_done_count) != 0) 551 ipmi_poll_interface(watchdog_user); 552 atomic_add(2, &panic_done_count); 553 rv = i_ipmi_set_timeout(&panic_halt_smi_msg, 554 &panic_halt_recv_msg, 555 &send_heartbeat_now); 556 if (rv) { 557 atomic_sub(2, &panic_done_count); 558 printk(KERN_WARNING PFX 559 "Unable to extend the watchdog timeout."); 560 } else { 561 if (send_heartbeat_now) 562 panic_halt_ipmi_heartbeat(); 563 } 564 while (atomic_read(&panic_done_count) != 0) 565 ipmi_poll_interface(watchdog_user); 566 } 567 568 /* 569 * We use a mutex to make sure that only one thing can send a 570 * heartbeat at one time, because we only have one copy of the data. 571 * The semaphore is claimed when the set_timeout is sent and freed 572 * when both messages are free. 573 */ 574 static atomic_t heartbeat_tofree = ATOMIC_INIT(0); 575 static DEFINE_MUTEX(heartbeat_lock); 576 static DECLARE_COMPLETION(heartbeat_wait); 577 static void heartbeat_free_smi(struct ipmi_smi_msg *msg) 578 { 579 if (atomic_dec_and_test(&heartbeat_tofree)) 580 complete(&heartbeat_wait); 581 } 582 static void heartbeat_free_recv(struct ipmi_recv_msg *msg) 583 { 584 if (atomic_dec_and_test(&heartbeat_tofree)) 585 complete(&heartbeat_wait); 586 } 587 static struct ipmi_smi_msg heartbeat_smi_msg = { 588 .done = heartbeat_free_smi 589 }; 590 static struct ipmi_recv_msg heartbeat_recv_msg = { 591 .done = heartbeat_free_recv 592 }; 593 594 static int ipmi_heartbeat(void) 595 { 596 struct kernel_ipmi_msg msg; 597 int rv; 598 struct ipmi_system_interface_addr addr; 599 int timeout_retries = 0; 600 601 if (ipmi_ignore_heartbeat) 602 return 0; 603 604 if (ipmi_start_timer_on_heartbeat) { 605 ipmi_start_timer_on_heartbeat = 0; 606 ipmi_watchdog_state = action_val; 607 return ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 608 } else if (pretimeout_since_last_heartbeat) { 609 /* 610 * A pretimeout occurred, make sure we set the timeout. 611 * We don't want to set the action, though, we want to 612 * leave that alone (thus it can't be combined with the 613 * above operation. 614 */ 615 return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 616 } 617 618 mutex_lock(&heartbeat_lock); 619 620 restart: 621 atomic_set(&heartbeat_tofree, 2); 622 623 /* 624 * Don't reset the timer if we have the timer turned off, that 625 * re-enables the watchdog. 626 */ 627 if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) { 628 mutex_unlock(&heartbeat_lock); 629 return 0; 630 } 631 632 addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE; 633 addr.channel = IPMI_BMC_CHANNEL; 634 addr.lun = 0; 635 636 msg.netfn = 0x06; 637 msg.cmd = IPMI_WDOG_RESET_TIMER; 638 msg.data = NULL; 639 msg.data_len = 0; 640 rv = ipmi_request_supply_msgs(watchdog_user, 641 (struct ipmi_addr *) &addr, 642 0, 643 &msg, 644 NULL, 645 &heartbeat_smi_msg, 646 &heartbeat_recv_msg, 647 1); 648 if (rv) { 649 mutex_unlock(&heartbeat_lock); 650 printk(KERN_WARNING PFX "heartbeat failure: %d\n", 651 rv); 652 return rv; 653 } 654 655 /* Wait for the heartbeat to be sent. */ 656 wait_for_completion(&heartbeat_wait); 657 658 if (heartbeat_recv_msg.msg.data[0] == IPMI_WDOG_TIMER_NOT_INIT_RESP) { 659 timeout_retries++; 660 if (timeout_retries > 3) { 661 printk(KERN_ERR PFX ": Unable to restore the IPMI" 662 " watchdog's settings, giving up.\n"); 663 rv = -EIO; 664 goto out_unlock; 665 } 666 667 /* 668 * The timer was not initialized, that means the BMC was 669 * probably reset and lost the watchdog information. Attempt 670 * to restore the timer's info. Note that we still hold 671 * the heartbeat lock, to keep a heartbeat from happening 672 * in this process, so must say no heartbeat to avoid a 673 * deadlock on this mutex. 674 */ 675 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 676 if (rv) { 677 printk(KERN_ERR PFX ": Unable to send the command to" 678 " set the watchdog's settings, giving up.\n"); 679 goto out_unlock; 680 } 681 682 /* We might need a new heartbeat, so do it now */ 683 goto restart; 684 } else if (heartbeat_recv_msg.msg.data[0] != 0) { 685 /* 686 * Got an error in the heartbeat response. It was already 687 * reported in ipmi_wdog_msg_handler, but we should return 688 * an error here. 689 */ 690 rv = -EINVAL; 691 } 692 693 out_unlock: 694 mutex_unlock(&heartbeat_lock); 695 696 return rv; 697 } 698 699 static struct watchdog_info ident = { 700 .options = 0, /* WDIOF_SETTIMEOUT, */ 701 .firmware_version = 1, 702 .identity = "IPMI" 703 }; 704 705 static int ipmi_ioctl(struct file *file, 706 unsigned int cmd, unsigned long arg) 707 { 708 void __user *argp = (void __user *)arg; 709 int i; 710 int val; 711 712 switch (cmd) { 713 case WDIOC_GETSUPPORT: 714 i = copy_to_user(argp, &ident, sizeof(ident)); 715 return i ? -EFAULT : 0; 716 717 case WDIOC_SETTIMEOUT: 718 i = copy_from_user(&val, argp, sizeof(int)); 719 if (i) 720 return -EFAULT; 721 timeout = val; 722 return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 723 724 case WDIOC_GETTIMEOUT: 725 i = copy_to_user(argp, &timeout, sizeof(timeout)); 726 if (i) 727 return -EFAULT; 728 return 0; 729 730 case WDIOC_SETPRETIMEOUT: 731 i = copy_from_user(&val, argp, sizeof(int)); 732 if (i) 733 return -EFAULT; 734 pretimeout = val; 735 return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 736 737 case WDIOC_GETPRETIMEOUT: 738 i = copy_to_user(argp, &pretimeout, sizeof(pretimeout)); 739 if (i) 740 return -EFAULT; 741 return 0; 742 743 case WDIOC_KEEPALIVE: 744 return ipmi_heartbeat(); 745 746 case WDIOC_SETOPTIONS: 747 i = copy_from_user(&val, argp, sizeof(int)); 748 if (i) 749 return -EFAULT; 750 if (val & WDIOS_DISABLECARD) { 751 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 752 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 753 ipmi_start_timer_on_heartbeat = 0; 754 } 755 756 if (val & WDIOS_ENABLECARD) { 757 ipmi_watchdog_state = action_val; 758 ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 759 } 760 return 0; 761 762 case WDIOC_GETSTATUS: 763 val = 0; 764 i = copy_to_user(argp, &val, sizeof(val)); 765 if (i) 766 return -EFAULT; 767 return 0; 768 769 default: 770 return -ENOIOCTLCMD; 771 } 772 } 773 774 static long ipmi_unlocked_ioctl(struct file *file, 775 unsigned int cmd, 776 unsigned long arg) 777 { 778 int ret; 779 780 mutex_lock(&ipmi_watchdog_mutex); 781 ret = ipmi_ioctl(file, cmd, arg); 782 mutex_unlock(&ipmi_watchdog_mutex); 783 784 return ret; 785 } 786 787 static ssize_t ipmi_write(struct file *file, 788 const char __user *buf, 789 size_t len, 790 loff_t *ppos) 791 { 792 int rv; 793 794 if (len) { 795 if (!nowayout) { 796 size_t i; 797 798 /* In case it was set long ago */ 799 expect_close = 0; 800 801 for (i = 0; i != len; i++) { 802 char c; 803 804 if (get_user(c, buf + i)) 805 return -EFAULT; 806 if (c == 'V') 807 expect_close = 42; 808 } 809 } 810 rv = ipmi_heartbeat(); 811 if (rv) 812 return rv; 813 } 814 return len; 815 } 816 817 static ssize_t ipmi_read(struct file *file, 818 char __user *buf, 819 size_t count, 820 loff_t *ppos) 821 { 822 int rv = 0; 823 wait_queue_t wait; 824 825 if (count <= 0) 826 return 0; 827 828 /* 829 * Reading returns if the pretimeout has gone off, and it only does 830 * it once per pretimeout. 831 */ 832 spin_lock(&ipmi_read_lock); 833 if (!data_to_read) { 834 if (file->f_flags & O_NONBLOCK) { 835 rv = -EAGAIN; 836 goto out; 837 } 838 839 init_waitqueue_entry(&wait, current); 840 add_wait_queue(&read_q, &wait); 841 while (!data_to_read) { 842 set_current_state(TASK_INTERRUPTIBLE); 843 spin_unlock(&ipmi_read_lock); 844 schedule(); 845 spin_lock(&ipmi_read_lock); 846 } 847 remove_wait_queue(&read_q, &wait); 848 849 if (signal_pending(current)) { 850 rv = -ERESTARTSYS; 851 goto out; 852 } 853 } 854 data_to_read = 0; 855 856 out: 857 spin_unlock(&ipmi_read_lock); 858 859 if (rv == 0) { 860 if (copy_to_user(buf, &data_to_read, 1)) 861 rv = -EFAULT; 862 else 863 rv = 1; 864 } 865 866 return rv; 867 } 868 869 static int ipmi_open(struct inode *ino, struct file *filep) 870 { 871 switch (iminor(ino)) { 872 case WATCHDOG_MINOR: 873 if (test_and_set_bit(0, &ipmi_wdog_open)) 874 return -EBUSY; 875 876 877 /* 878 * Don't start the timer now, let it start on the 879 * first heartbeat. 880 */ 881 ipmi_start_timer_on_heartbeat = 1; 882 return nonseekable_open(ino, filep); 883 884 default: 885 return (-ENODEV); 886 } 887 } 888 889 static unsigned int ipmi_poll(struct file *file, poll_table *wait) 890 { 891 unsigned int mask = 0; 892 893 poll_wait(file, &read_q, wait); 894 895 spin_lock(&ipmi_read_lock); 896 if (data_to_read) 897 mask |= (POLLIN | POLLRDNORM); 898 spin_unlock(&ipmi_read_lock); 899 900 return mask; 901 } 902 903 static int ipmi_fasync(int fd, struct file *file, int on) 904 { 905 int result; 906 907 result = fasync_helper(fd, file, on, &fasync_q); 908 909 return (result); 910 } 911 912 static int ipmi_close(struct inode *ino, struct file *filep) 913 { 914 if (iminor(ino) == WATCHDOG_MINOR) { 915 if (expect_close == 42) { 916 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 917 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 918 } else { 919 printk(KERN_CRIT PFX 920 "Unexpected close, not stopping watchdog!\n"); 921 ipmi_heartbeat(); 922 } 923 clear_bit(0, &ipmi_wdog_open); 924 } 925 926 expect_close = 0; 927 928 return 0; 929 } 930 931 static const struct file_operations ipmi_wdog_fops = { 932 .owner = THIS_MODULE, 933 .read = ipmi_read, 934 .poll = ipmi_poll, 935 .write = ipmi_write, 936 .unlocked_ioctl = ipmi_unlocked_ioctl, 937 .open = ipmi_open, 938 .release = ipmi_close, 939 .fasync = ipmi_fasync, 940 .llseek = no_llseek, 941 }; 942 943 static struct miscdevice ipmi_wdog_miscdev = { 944 .minor = WATCHDOG_MINOR, 945 .name = "watchdog", 946 .fops = &ipmi_wdog_fops 947 }; 948 949 static void ipmi_wdog_msg_handler(struct ipmi_recv_msg *msg, 950 void *handler_data) 951 { 952 if (msg->msg.cmd == IPMI_WDOG_RESET_TIMER && 953 msg->msg.data[0] == IPMI_WDOG_TIMER_NOT_INIT_RESP) 954 printk(KERN_INFO PFX "response: The IPMI controller appears" 955 " to have been reset, will attempt to reinitialize" 956 " the watchdog timer\n"); 957 else if (msg->msg.data[0] != 0) 958 printk(KERN_ERR PFX "response: Error %x on cmd %x\n", 959 msg->msg.data[0], 960 msg->msg.cmd); 961 962 ipmi_free_recv_msg(msg); 963 } 964 965 static void ipmi_wdog_pretimeout_handler(void *handler_data) 966 { 967 if (preaction_val != WDOG_PRETIMEOUT_NONE) { 968 if (preop_val == WDOG_PREOP_PANIC) { 969 if (atomic_inc_and_test(&preop_panic_excl)) 970 panic("Watchdog pre-timeout"); 971 } else if (preop_val == WDOG_PREOP_GIVE_DATA) { 972 spin_lock(&ipmi_read_lock); 973 data_to_read = 1; 974 wake_up_interruptible(&read_q); 975 kill_fasync(&fasync_q, SIGIO, POLL_IN); 976 977 spin_unlock(&ipmi_read_lock); 978 } 979 } 980 981 /* 982 * On some machines, the heartbeat will give an error and not 983 * work unless we re-enable the timer. So do so. 984 */ 985 pretimeout_since_last_heartbeat = 1; 986 } 987 988 static struct ipmi_user_hndl ipmi_hndlrs = { 989 .ipmi_recv_hndl = ipmi_wdog_msg_handler, 990 .ipmi_watchdog_pretimeout = ipmi_wdog_pretimeout_handler 991 }; 992 993 static void ipmi_register_watchdog(int ipmi_intf) 994 { 995 int rv = -EBUSY; 996 997 if (watchdog_user) 998 goto out; 999 1000 if ((ifnum_to_use >= 0) && (ifnum_to_use != ipmi_intf)) 1001 goto out; 1002 1003 watchdog_ifnum = ipmi_intf; 1004 1005 rv = ipmi_create_user(ipmi_intf, &ipmi_hndlrs, NULL, &watchdog_user); 1006 if (rv < 0) { 1007 printk(KERN_CRIT PFX "Unable to register with ipmi\n"); 1008 goto out; 1009 } 1010 1011 ipmi_get_version(watchdog_user, 1012 &ipmi_version_major, 1013 &ipmi_version_minor); 1014 1015 rv = misc_register(&ipmi_wdog_miscdev); 1016 if (rv < 0) { 1017 ipmi_destroy_user(watchdog_user); 1018 watchdog_user = NULL; 1019 printk(KERN_CRIT PFX "Unable to register misc device\n"); 1020 } 1021 1022 #ifdef HAVE_DIE_NMI 1023 if (nmi_handler_registered) { 1024 int old_pretimeout = pretimeout; 1025 int old_timeout = timeout; 1026 int old_preop_val = preop_val; 1027 1028 /* 1029 * Set the pretimeout to go off in a second and give 1030 * ourselves plenty of time to stop the timer. 1031 */ 1032 ipmi_watchdog_state = WDOG_TIMEOUT_RESET; 1033 preop_val = WDOG_PREOP_NONE; /* Make sure nothing happens */ 1034 pretimeout = 99; 1035 timeout = 100; 1036 1037 testing_nmi = 1; 1038 1039 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 1040 if (rv) { 1041 printk(KERN_WARNING PFX "Error starting timer to" 1042 " test NMI: 0x%x. The NMI pretimeout will" 1043 " likely not work\n", rv); 1044 rv = 0; 1045 goto out_restore; 1046 } 1047 1048 msleep(1500); 1049 1050 if (testing_nmi != 2) { 1051 printk(KERN_WARNING PFX "IPMI NMI didn't seem to" 1052 " occur. The NMI pretimeout will" 1053 " likely not work\n"); 1054 } 1055 out_restore: 1056 testing_nmi = 0; 1057 preop_val = old_preop_val; 1058 pretimeout = old_pretimeout; 1059 timeout = old_timeout; 1060 } 1061 #endif 1062 1063 out: 1064 if ((start_now) && (rv == 0)) { 1065 /* Run from startup, so start the timer now. */ 1066 start_now = 0; /* Disable this function after first startup. */ 1067 ipmi_watchdog_state = action_val; 1068 ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 1069 printk(KERN_INFO PFX "Starting now!\n"); 1070 } else { 1071 /* Stop the timer now. */ 1072 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 1073 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 1074 } 1075 } 1076 1077 static void ipmi_unregister_watchdog(int ipmi_intf) 1078 { 1079 int rv; 1080 1081 if (!watchdog_user) 1082 goto out; 1083 1084 if (watchdog_ifnum != ipmi_intf) 1085 goto out; 1086 1087 /* Make sure no one can call us any more. */ 1088 misc_deregister(&ipmi_wdog_miscdev); 1089 1090 /* 1091 * Wait to make sure the message makes it out. The lower layer has 1092 * pointers to our buffers, we want to make sure they are done before 1093 * we release our memory. 1094 */ 1095 while (atomic_read(&set_timeout_tofree)) 1096 schedule_timeout_uninterruptible(1); 1097 1098 /* Disconnect from IPMI. */ 1099 rv = ipmi_destroy_user(watchdog_user); 1100 if (rv) { 1101 printk(KERN_WARNING PFX "error unlinking from IPMI: %d\n", 1102 rv); 1103 } 1104 watchdog_user = NULL; 1105 1106 out: 1107 return; 1108 } 1109 1110 #ifdef HAVE_DIE_NMI 1111 static int 1112 ipmi_nmi(unsigned int val, struct pt_regs *regs) 1113 { 1114 /* 1115 * If we get here, it's an NMI that's not a memory or I/O 1116 * error. We can't truly tell if it's from IPMI or not 1117 * without sending a message, and sending a message is almost 1118 * impossible because of locking. 1119 */ 1120 1121 if (testing_nmi) { 1122 testing_nmi = 2; 1123 return NMI_HANDLED; 1124 } 1125 1126 /* If we are not expecting a timeout, ignore it. */ 1127 if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) 1128 return NMI_DONE; 1129 1130 if (preaction_val != WDOG_PRETIMEOUT_NMI) 1131 return NMI_DONE; 1132 1133 /* 1134 * If no one else handled the NMI, we assume it was the IPMI 1135 * watchdog. 1136 */ 1137 if (preop_val == WDOG_PREOP_PANIC) { 1138 /* On some machines, the heartbeat will give 1139 an error and not work unless we re-enable 1140 the timer. So do so. */ 1141 pretimeout_since_last_heartbeat = 1; 1142 if (atomic_inc_and_test(&preop_panic_excl)) 1143 nmi_panic(regs, PFX "pre-timeout"); 1144 } 1145 1146 return NMI_HANDLED; 1147 } 1148 #endif 1149 1150 static int wdog_reboot_handler(struct notifier_block *this, 1151 unsigned long code, 1152 void *unused) 1153 { 1154 static int reboot_event_handled; 1155 1156 if ((watchdog_user) && (!reboot_event_handled)) { 1157 /* Make sure we only do this once. */ 1158 reboot_event_handled = 1; 1159 1160 if (code == SYS_POWER_OFF || code == SYS_HALT) { 1161 /* Disable the WDT if we are shutting down. */ 1162 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 1163 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 1164 } else if (ipmi_watchdog_state != WDOG_TIMEOUT_NONE) { 1165 /* Set a long timer to let the reboot happens, but 1166 reboot if it hangs, but only if the watchdog 1167 timer was already running. */ 1168 timeout = 120; 1169 pretimeout = 0; 1170 ipmi_watchdog_state = WDOG_TIMEOUT_RESET; 1171 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 1172 } 1173 } 1174 return NOTIFY_OK; 1175 } 1176 1177 static struct notifier_block wdog_reboot_notifier = { 1178 .notifier_call = wdog_reboot_handler, 1179 .next = NULL, 1180 .priority = 0 1181 }; 1182 1183 static int wdog_panic_handler(struct notifier_block *this, 1184 unsigned long event, 1185 void *unused) 1186 { 1187 static int panic_event_handled; 1188 1189 /* On a panic, if we have a panic timeout, make sure to extend 1190 the watchdog timer to a reasonable value to complete the 1191 panic, if the watchdog timer is running. Plus the 1192 pretimeout is meaningless at panic time. */ 1193 if (watchdog_user && !panic_event_handled && 1194 ipmi_watchdog_state != WDOG_TIMEOUT_NONE) { 1195 /* Make sure we do this only once. */ 1196 panic_event_handled = 1; 1197 1198 timeout = panic_wdt_timeout; 1199 pretimeout = 0; 1200 panic_halt_ipmi_set_timeout(); 1201 } 1202 1203 return NOTIFY_OK; 1204 } 1205 1206 static struct notifier_block wdog_panic_notifier = { 1207 .notifier_call = wdog_panic_handler, 1208 .next = NULL, 1209 .priority = 150 /* priority: INT_MAX >= x >= 0 */ 1210 }; 1211 1212 1213 static void ipmi_new_smi(int if_num, struct device *device) 1214 { 1215 ipmi_register_watchdog(if_num); 1216 } 1217 1218 static void ipmi_smi_gone(int if_num) 1219 { 1220 ipmi_unregister_watchdog(if_num); 1221 } 1222 1223 static struct ipmi_smi_watcher smi_watcher = { 1224 .owner = THIS_MODULE, 1225 .new_smi = ipmi_new_smi, 1226 .smi_gone = ipmi_smi_gone 1227 }; 1228 1229 static int action_op(const char *inval, char *outval) 1230 { 1231 if (outval) 1232 strcpy(outval, action); 1233 1234 if (!inval) 1235 return 0; 1236 1237 if (strcmp(inval, "reset") == 0) 1238 action_val = WDOG_TIMEOUT_RESET; 1239 else if (strcmp(inval, "none") == 0) 1240 action_val = WDOG_TIMEOUT_NONE; 1241 else if (strcmp(inval, "power_cycle") == 0) 1242 action_val = WDOG_TIMEOUT_POWER_CYCLE; 1243 else if (strcmp(inval, "power_off") == 0) 1244 action_val = WDOG_TIMEOUT_POWER_DOWN; 1245 else 1246 return -EINVAL; 1247 strcpy(action, inval); 1248 return 0; 1249 } 1250 1251 static int preaction_op(const char *inval, char *outval) 1252 { 1253 if (outval) 1254 strcpy(outval, preaction); 1255 1256 if (!inval) 1257 return 0; 1258 1259 if (strcmp(inval, "pre_none") == 0) 1260 preaction_val = WDOG_PRETIMEOUT_NONE; 1261 else if (strcmp(inval, "pre_smi") == 0) 1262 preaction_val = WDOG_PRETIMEOUT_SMI; 1263 #ifdef HAVE_DIE_NMI 1264 else if (strcmp(inval, "pre_nmi") == 0) 1265 preaction_val = WDOG_PRETIMEOUT_NMI; 1266 #endif 1267 else if (strcmp(inval, "pre_int") == 0) 1268 preaction_val = WDOG_PRETIMEOUT_MSG_INT; 1269 else 1270 return -EINVAL; 1271 strcpy(preaction, inval); 1272 return 0; 1273 } 1274 1275 static int preop_op(const char *inval, char *outval) 1276 { 1277 if (outval) 1278 strcpy(outval, preop); 1279 1280 if (!inval) 1281 return 0; 1282 1283 if (strcmp(inval, "preop_none") == 0) 1284 preop_val = WDOG_PREOP_NONE; 1285 else if (strcmp(inval, "preop_panic") == 0) 1286 preop_val = WDOG_PREOP_PANIC; 1287 else if (strcmp(inval, "preop_give_data") == 0) 1288 preop_val = WDOG_PREOP_GIVE_DATA; 1289 else 1290 return -EINVAL; 1291 strcpy(preop, inval); 1292 return 0; 1293 } 1294 1295 static void check_parms(void) 1296 { 1297 #ifdef HAVE_DIE_NMI 1298 int do_nmi = 0; 1299 int rv; 1300 1301 if (preaction_val == WDOG_PRETIMEOUT_NMI) { 1302 do_nmi = 1; 1303 if (preop_val == WDOG_PREOP_GIVE_DATA) { 1304 printk(KERN_WARNING PFX "Pretimeout op is to give data" 1305 " but NMI pretimeout is enabled, setting" 1306 " pretimeout op to none\n"); 1307 preop_op("preop_none", NULL); 1308 do_nmi = 0; 1309 } 1310 } 1311 if (do_nmi && !nmi_handler_registered) { 1312 rv = register_nmi_handler(NMI_UNKNOWN, ipmi_nmi, 0, 1313 "ipmi"); 1314 if (rv) { 1315 printk(KERN_WARNING PFX 1316 "Can't register nmi handler\n"); 1317 return; 1318 } else 1319 nmi_handler_registered = 1; 1320 } else if (!do_nmi && nmi_handler_registered) { 1321 unregister_nmi_handler(NMI_UNKNOWN, "ipmi"); 1322 nmi_handler_registered = 0; 1323 } 1324 #endif 1325 } 1326 1327 static int __init ipmi_wdog_init(void) 1328 { 1329 int rv; 1330 1331 if (action_op(action, NULL)) { 1332 action_op("reset", NULL); 1333 printk(KERN_INFO PFX "Unknown action '%s', defaulting to" 1334 " reset\n", action); 1335 } 1336 1337 if (preaction_op(preaction, NULL)) { 1338 preaction_op("pre_none", NULL); 1339 printk(KERN_INFO PFX "Unknown preaction '%s', defaulting to" 1340 " none\n", preaction); 1341 } 1342 1343 if (preop_op(preop, NULL)) { 1344 preop_op("preop_none", NULL); 1345 printk(KERN_INFO PFX "Unknown preop '%s', defaulting to" 1346 " none\n", preop); 1347 } 1348 1349 check_parms(); 1350 1351 register_reboot_notifier(&wdog_reboot_notifier); 1352 atomic_notifier_chain_register(&panic_notifier_list, 1353 &wdog_panic_notifier); 1354 1355 rv = ipmi_smi_watcher_register(&smi_watcher); 1356 if (rv) { 1357 #ifdef HAVE_DIE_NMI 1358 if (nmi_handler_registered) 1359 unregister_nmi_handler(NMI_UNKNOWN, "ipmi"); 1360 #endif 1361 atomic_notifier_chain_unregister(&panic_notifier_list, 1362 &wdog_panic_notifier); 1363 unregister_reboot_notifier(&wdog_reboot_notifier); 1364 printk(KERN_WARNING PFX "can't register smi watcher\n"); 1365 return rv; 1366 } 1367 1368 printk(KERN_INFO PFX "driver initialized\n"); 1369 1370 return 0; 1371 } 1372 1373 static void __exit ipmi_wdog_exit(void) 1374 { 1375 ipmi_smi_watcher_unregister(&smi_watcher); 1376 ipmi_unregister_watchdog(watchdog_ifnum); 1377 1378 #ifdef HAVE_DIE_NMI 1379 if (nmi_handler_registered) 1380 unregister_nmi_handler(NMI_UNKNOWN, "ipmi"); 1381 #endif 1382 1383 atomic_notifier_chain_unregister(&panic_notifier_list, 1384 &wdog_panic_notifier); 1385 unregister_reboot_notifier(&wdog_reboot_notifier); 1386 } 1387 module_exit(ipmi_wdog_exit); 1388 module_init(ipmi_wdog_init); 1389 MODULE_LICENSE("GPL"); 1390 MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>"); 1391 MODULE_DESCRIPTION("watchdog timer based upon the IPMI interface."); 1392