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/* These are here until the real ones get into the watchdog.h interface. */ 145#ifndef WDIOC_GETTIMEOUT 146#define WDIOC_GETTIMEOUT _IOW(WATCHDOG_IOCTL_BASE, 20, int) 147#endif 148#ifndef WDIOC_SET_PRETIMEOUT 149#define WDIOC_SET_PRETIMEOUT _IOW(WATCHDOG_IOCTL_BASE, 21, int) 150#endif 151#ifndef WDIOC_GET_PRETIMEOUT 152#define WDIOC_GET_PRETIMEOUT _IOW(WATCHDOG_IOCTL_BASE, 22, int) 153#endif 154 155static DEFINE_MUTEX(ipmi_watchdog_mutex); 156static int nowayout = WATCHDOG_NOWAYOUT; 157 158static ipmi_user_t watchdog_user; 159static int watchdog_ifnum; 160 161/* Default the timeout to 10 seconds. */ 162static int timeout = 10; 163 164/* The pre-timeout is disabled by default. */ 165static int pretimeout; 166 167/* Default action is to reset the board on a timeout. */ 168static unsigned char action_val = WDOG_TIMEOUT_RESET; 169 170static char action[16] = "reset"; 171 172static unsigned char preaction_val = WDOG_PRETIMEOUT_NONE; 173 174static char preaction[16] = "pre_none"; 175 176static unsigned char preop_val = WDOG_PREOP_NONE; 177 178static char preop[16] = "preop_none"; 179static DEFINE_SPINLOCK(ipmi_read_lock); 180static char data_to_read; 181static DECLARE_WAIT_QUEUE_HEAD(read_q); 182static struct fasync_struct *fasync_q; 183static char pretimeout_since_last_heartbeat; 184static char expect_close; 185 186static int ifnum_to_use = -1; 187 188/* Parameters to ipmi_set_timeout */ 189#define IPMI_SET_TIMEOUT_NO_HB 0 190#define IPMI_SET_TIMEOUT_HB_IF_NECESSARY 1 191#define IPMI_SET_TIMEOUT_FORCE_HB 2 192 193static int ipmi_set_timeout(int do_heartbeat); 194static void ipmi_register_watchdog(int ipmi_intf); 195static void ipmi_unregister_watchdog(int ipmi_intf); 196 197/* 198 * If true, the driver will start running as soon as it is configured 199 * and ready. 200 */ 201static int start_now; 202 203static int set_param_timeout(const char *val, const struct kernel_param *kp) 204{ 205 char *endp; 206 int l; 207 int rv = 0; 208 209 if (!val) 210 return -EINVAL; 211 l = simple_strtoul(val, &endp, 0); 212 if (endp == val) 213 return -EINVAL; 214 215 *((int *)kp->arg) = l; 216 if (watchdog_user) 217 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 218 219 return rv; 220} 221 222static struct kernel_param_ops param_ops_timeout = { 223 .set = set_param_timeout, 224 .get = param_get_int, 225}; 226#define param_check_timeout param_check_int 227 228typedef int (*action_fn)(const char *intval, char *outval); 229 230static int action_op(const char *inval, char *outval); 231static int preaction_op(const char *inval, char *outval); 232static int preop_op(const char *inval, char *outval); 233static void check_parms(void); 234 235static int set_param_str(const char *val, const struct kernel_param *kp) 236{ 237 action_fn fn = (action_fn) kp->arg; 238 int rv = 0; 239 char valcp[16]; 240 char *s; 241 242 strncpy(valcp, val, 16); 243 valcp[15] = '\0'; 244 245 s = strstrip(valcp); 246 247 rv = fn(s, NULL); 248 if (rv) 249 goto out; 250 251 check_parms(); 252 if (watchdog_user) 253 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 254 255 out: 256 return rv; 257} 258 259static int get_param_str(char *buffer, const struct kernel_param *kp) 260{ 261 action_fn fn = (action_fn) kp->arg; 262 int rv; 263 264 rv = fn(NULL, buffer); 265 if (rv) 266 return rv; 267 return strlen(buffer); 268} 269 270 271static int set_param_wdog_ifnum(const char *val, const struct kernel_param *kp) 272{ 273 int rv = param_set_int(val, kp); 274 if (rv) 275 return rv; 276 if ((ifnum_to_use < 0) || (ifnum_to_use == watchdog_ifnum)) 277 return 0; 278 279 ipmi_unregister_watchdog(watchdog_ifnum); 280 ipmi_register_watchdog(ifnum_to_use); 281 return 0; 282} 283 284static struct kernel_param_ops param_ops_wdog_ifnum = { 285 .set = set_param_wdog_ifnum, 286 .get = param_get_int, 287}; 288 289#define param_check_wdog_ifnum param_check_int 290 291static struct kernel_param_ops param_ops_str = { 292 .set = set_param_str, 293 .get = get_param_str, 294}; 295 296module_param(ifnum_to_use, wdog_ifnum, 0644); 297MODULE_PARM_DESC(ifnum_to_use, "The interface number to use for the watchdog " 298 "timer. Setting to -1 defaults to the first registered " 299 "interface"); 300 301module_param(timeout, timeout, 0644); 302MODULE_PARM_DESC(timeout, "Timeout value in seconds."); 303 304module_param(pretimeout, timeout, 0644); 305MODULE_PARM_DESC(pretimeout, "Pretimeout value in seconds."); 306 307module_param_cb(action, ¶m_ops_str, action_op, 0644); 308MODULE_PARM_DESC(action, "Timeout action. One of: " 309 "reset, none, power_cycle, power_off."); 310 311module_param_cb(preaction, ¶m_ops_str, preaction_op, 0644); 312MODULE_PARM_DESC(preaction, "Pretimeout action. One of: " 313 "pre_none, pre_smi, pre_nmi, pre_int."); 314 315module_param_cb(preop, ¶m_ops_str, preop_op, 0644); 316MODULE_PARM_DESC(preop, "Pretimeout driver operation. One of: " 317 "preop_none, preop_panic, preop_give_data."); 318 319module_param(start_now, int, 0444); 320MODULE_PARM_DESC(start_now, "Set to 1 to start the watchdog as" 321 "soon as the driver is loaded."); 322 323module_param(nowayout, int, 0644); 324MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " 325 "(default=CONFIG_WATCHDOG_NOWAYOUT)"); 326 327/* Default state of the timer. */ 328static unsigned char ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 329 330/* If shutting down via IPMI, we ignore the heartbeat. */ 331static int ipmi_ignore_heartbeat; 332 333/* Is someone using the watchdog? Only one user is allowed. */ 334static unsigned long ipmi_wdog_open; 335 336/* 337 * If set to 1, the heartbeat command will set the state to reset and 338 * start the timer. The timer doesn't normally run when the driver is 339 * first opened until the heartbeat is set the first time, this 340 * variable is used to accomplish this. 341 */ 342static int ipmi_start_timer_on_heartbeat; 343 344/* IPMI version of the BMC. */ 345static unsigned char ipmi_version_major; 346static unsigned char ipmi_version_minor; 347 348/* If a pretimeout occurs, this is used to allow only one panic to happen. */ 349static atomic_t preop_panic_excl = ATOMIC_INIT(-1); 350 351#ifdef HAVE_DIE_NMI 352static int testing_nmi; 353static int nmi_handler_registered; 354#endif 355 356static int ipmi_heartbeat(void); 357 358/* 359 * We use a mutex to make sure that only one thing can send a set 360 * timeout at one time, because we only have one copy of the data. 361 * The mutex is claimed when the set_timeout is sent and freed 362 * when both messages are free. 363 */ 364static atomic_t set_timeout_tofree = ATOMIC_INIT(0); 365static DEFINE_MUTEX(set_timeout_lock); 366static DECLARE_COMPLETION(set_timeout_wait); 367static void set_timeout_free_smi(struct ipmi_smi_msg *msg) 368{ 369 if (atomic_dec_and_test(&set_timeout_tofree)) 370 complete(&set_timeout_wait); 371} 372static void set_timeout_free_recv(struct ipmi_recv_msg *msg) 373{ 374 if (atomic_dec_and_test(&set_timeout_tofree)) 375 complete(&set_timeout_wait); 376} 377static struct ipmi_smi_msg set_timeout_smi_msg = { 378 .done = set_timeout_free_smi 379}; 380static struct ipmi_recv_msg set_timeout_recv_msg = { 381 .done = set_timeout_free_recv 382}; 383 384static int i_ipmi_set_timeout(struct ipmi_smi_msg *smi_msg, 385 struct ipmi_recv_msg *recv_msg, 386 int *send_heartbeat_now) 387{ 388 struct kernel_ipmi_msg msg; 389 unsigned char data[6]; 390 int rv; 391 struct ipmi_system_interface_addr addr; 392 int hbnow = 0; 393 394 395 /* These can be cleared as we are setting the timeout. */ 396 pretimeout_since_last_heartbeat = 0; 397 398 data[0] = 0; 399 WDOG_SET_TIMER_USE(data[0], WDOG_TIMER_USE_SMS_OS); 400 401 if ((ipmi_version_major > 1) 402 || ((ipmi_version_major == 1) && (ipmi_version_minor >= 5))) { 403 /* This is an IPMI 1.5-only feature. */ 404 data[0] |= WDOG_DONT_STOP_ON_SET; 405 } else if (ipmi_watchdog_state != WDOG_TIMEOUT_NONE) { 406 /* 407 * In ipmi 1.0, setting the timer stops the watchdog, we 408 * need to start it back up again. 409 */ 410 hbnow = 1; 411 } 412 413 data[1] = 0; 414 WDOG_SET_TIMEOUT_ACT(data[1], ipmi_watchdog_state); 415 if ((pretimeout > 0) && (ipmi_watchdog_state != WDOG_TIMEOUT_NONE)) { 416 WDOG_SET_PRETIMEOUT_ACT(data[1], preaction_val); 417 data[2] = pretimeout; 418 } else { 419 WDOG_SET_PRETIMEOUT_ACT(data[1], WDOG_PRETIMEOUT_NONE); 420 data[2] = 0; /* No pretimeout. */ 421 } 422 data[3] = 0; 423 WDOG_SET_TIMEOUT(data[4], data[5], timeout); 424 425 addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE; 426 addr.channel = IPMI_BMC_CHANNEL; 427 addr.lun = 0; 428 429 msg.netfn = 0x06; 430 msg.cmd = IPMI_WDOG_SET_TIMER; 431 msg.data = data; 432 msg.data_len = sizeof(data); 433 rv = ipmi_request_supply_msgs(watchdog_user, 434 (struct ipmi_addr *) &addr, 435 0, 436 &msg, 437 NULL, 438 smi_msg, 439 recv_msg, 440 1); 441 if (rv) { 442 printk(KERN_WARNING PFX "set timeout error: %d\n", 443 rv); 444 } 445 446 if (send_heartbeat_now) 447 *send_heartbeat_now = hbnow; 448 449 return rv; 450} 451 452static int ipmi_set_timeout(int do_heartbeat) 453{ 454 int send_heartbeat_now; 455 int rv; 456 457 458 /* We can only send one of these at a time. */ 459 mutex_lock(&set_timeout_lock); 460 461 atomic_set(&set_timeout_tofree, 2); 462 463 rv = i_ipmi_set_timeout(&set_timeout_smi_msg, 464 &set_timeout_recv_msg, 465 &send_heartbeat_now); 466 if (rv) { 467 mutex_unlock(&set_timeout_lock); 468 goto out; 469 } 470 471 wait_for_completion(&set_timeout_wait); 472 473 mutex_unlock(&set_timeout_lock); 474 475 if ((do_heartbeat == IPMI_SET_TIMEOUT_FORCE_HB) 476 || ((send_heartbeat_now) 477 && (do_heartbeat == IPMI_SET_TIMEOUT_HB_IF_NECESSARY))) 478 rv = ipmi_heartbeat(); 479 480out: 481 return rv; 482} 483 484static atomic_t panic_done_count = ATOMIC_INIT(0); 485 486static void panic_smi_free(struct ipmi_smi_msg *msg) 487{ 488 atomic_dec(&panic_done_count); 489} 490static void panic_recv_free(struct ipmi_recv_msg *msg) 491{ 492 atomic_dec(&panic_done_count); 493} 494 495static struct ipmi_smi_msg panic_halt_heartbeat_smi_msg = { 496 .done = panic_smi_free 497}; 498static struct ipmi_recv_msg panic_halt_heartbeat_recv_msg = { 499 .done = panic_recv_free 500}; 501 502static void panic_halt_ipmi_heartbeat(void) 503{ 504 struct kernel_ipmi_msg msg; 505 struct ipmi_system_interface_addr addr; 506 int rv; 507 508 /* 509 * Don't reset the timer if we have the timer turned off, that 510 * re-enables the watchdog. 511 */ 512 if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) 513 return; 514 515 addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE; 516 addr.channel = IPMI_BMC_CHANNEL; 517 addr.lun = 0; 518 519 msg.netfn = 0x06; 520 msg.cmd = IPMI_WDOG_RESET_TIMER; 521 msg.data = NULL; 522 msg.data_len = 0; 523 rv = ipmi_request_supply_msgs(watchdog_user, 524 (struct ipmi_addr *) &addr, 525 0, 526 &msg, 527 NULL, 528 &panic_halt_heartbeat_smi_msg, 529 &panic_halt_heartbeat_recv_msg, 530 1); 531 if (!rv) 532 atomic_add(2, &panic_done_count); 533} 534 535static struct ipmi_smi_msg panic_halt_smi_msg = { 536 .done = panic_smi_free 537}; 538static struct ipmi_recv_msg panic_halt_recv_msg = { 539 .done = panic_recv_free 540}; 541 542/* 543 * Special call, doesn't claim any locks. This is only to be called 544 * at panic or halt time, in run-to-completion mode, when the caller 545 * is the only CPU and the only thing that will be going is these IPMI 546 * calls. 547 */ 548static void panic_halt_ipmi_set_timeout(void) 549{ 550 int send_heartbeat_now; 551 int rv; 552 553 /* Wait for the messages to be free. */ 554 while (atomic_read(&panic_done_count) != 0) 555 ipmi_poll_interface(watchdog_user); 556 rv = i_ipmi_set_timeout(&panic_halt_smi_msg, 557 &panic_halt_recv_msg, 558 &send_heartbeat_now); 559 if (!rv) { 560 atomic_add(2, &panic_done_count); 561 if (send_heartbeat_now) 562 panic_halt_ipmi_heartbeat(); 563 } else 564 printk(KERN_WARNING PFX 565 "Unable to extend the watchdog timeout."); 566 while (atomic_read(&panic_done_count) != 0) 567 ipmi_poll_interface(watchdog_user); 568} 569 570/* 571 * We use a mutex to make sure that only one thing can send a 572 * heartbeat at one time, because we only have one copy of the data. 573 * The semaphore is claimed when the set_timeout is sent and freed 574 * when both messages are free. 575 */ 576static atomic_t heartbeat_tofree = ATOMIC_INIT(0); 577static DEFINE_MUTEX(heartbeat_lock); 578static DECLARE_COMPLETION(heartbeat_wait); 579static void heartbeat_free_smi(struct ipmi_smi_msg *msg) 580{ 581 if (atomic_dec_and_test(&heartbeat_tofree)) 582 complete(&heartbeat_wait); 583} 584static void heartbeat_free_recv(struct ipmi_recv_msg *msg) 585{ 586 if (atomic_dec_and_test(&heartbeat_tofree)) 587 complete(&heartbeat_wait); 588} 589static struct ipmi_smi_msg heartbeat_smi_msg = { 590 .done = heartbeat_free_smi 591}; 592static struct ipmi_recv_msg heartbeat_recv_msg = { 593 .done = heartbeat_free_recv 594}; 595 596static int ipmi_heartbeat(void) 597{ 598 struct kernel_ipmi_msg msg; 599 int rv; 600 struct ipmi_system_interface_addr addr; 601 int timeout_retries = 0; 602 603 if (ipmi_ignore_heartbeat) 604 return 0; 605 606 if (ipmi_start_timer_on_heartbeat) { 607 ipmi_start_timer_on_heartbeat = 0; 608 ipmi_watchdog_state = action_val; 609 return ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 610 } else if (pretimeout_since_last_heartbeat) { 611 /* 612 * A pretimeout occurred, make sure we set the timeout. 613 * We don't want to set the action, though, we want to 614 * leave that alone (thus it can't be combined with the 615 * above operation. 616 */ 617 return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 618 } 619 620 mutex_lock(&heartbeat_lock); 621 622restart: 623 atomic_set(&heartbeat_tofree, 2); 624 625 /* 626 * Don't reset the timer if we have the timer turned off, that 627 * re-enables the watchdog. 628 */ 629 if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) { 630 mutex_unlock(&heartbeat_lock); 631 return 0; 632 } 633 634 addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE; 635 addr.channel = IPMI_BMC_CHANNEL; 636 addr.lun = 0; 637 638 msg.netfn = 0x06; 639 msg.cmd = IPMI_WDOG_RESET_TIMER; 640 msg.data = NULL; 641 msg.data_len = 0; 642 rv = ipmi_request_supply_msgs(watchdog_user, 643 (struct ipmi_addr *) &addr, 644 0, 645 &msg, 646 NULL, 647 &heartbeat_smi_msg, 648 &heartbeat_recv_msg, 649 1); 650 if (rv) { 651 mutex_unlock(&heartbeat_lock); 652 printk(KERN_WARNING PFX "heartbeat failure: %d\n", 653 rv); 654 return rv; 655 } 656 657 /* Wait for the heartbeat to be sent. */ 658 wait_for_completion(&heartbeat_wait); 659 660 if (heartbeat_recv_msg.msg.data[0] == IPMI_WDOG_TIMER_NOT_INIT_RESP) { 661 timeout_retries++; 662 if (timeout_retries > 3) { 663 printk(KERN_ERR PFX ": Unable to restore the IPMI" 664 " watchdog's settings, giving up.\n"); 665 rv = -EIO; 666 goto out_unlock; 667 } 668 669 /* 670 * The timer was not initialized, that means the BMC was 671 * probably reset and lost the watchdog information. Attempt 672 * to restore the timer's info. Note that we still hold 673 * the heartbeat lock, to keep a heartbeat from happening 674 * in this process, so must say no heartbeat to avoid a 675 * deadlock on this mutex. 676 */ 677 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 678 if (rv) { 679 printk(KERN_ERR PFX ": Unable to send the command to" 680 " set the watchdog's settings, giving up.\n"); 681 goto out_unlock; 682 } 683 684 /* We might need a new heartbeat, so do it now */ 685 goto restart; 686 } else if (heartbeat_recv_msg.msg.data[0] != 0) { 687 /* 688 * Got an error in the heartbeat response. It was already 689 * reported in ipmi_wdog_msg_handler, but we should return 690 * an error here. 691 */ 692 rv = -EINVAL; 693 } 694 695out_unlock: 696 mutex_unlock(&heartbeat_lock); 697 698 return rv; 699} 700 701static struct watchdog_info ident = { 702 .options = 0, /* WDIOF_SETTIMEOUT, */ 703 .firmware_version = 1, 704 .identity = "IPMI" 705}; 706 707static int ipmi_ioctl(struct file *file, 708 unsigned int cmd, unsigned long arg) 709{ 710 void __user *argp = (void __user *)arg; 711 int i; 712 int val; 713 714 switch (cmd) { 715 case WDIOC_GETSUPPORT: 716 i = copy_to_user(argp, &ident, sizeof(ident)); 717 return i ? -EFAULT : 0; 718 719 case WDIOC_SETTIMEOUT: 720 i = copy_from_user(&val, argp, sizeof(int)); 721 if (i) 722 return -EFAULT; 723 timeout = val; 724 return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 725 726 case WDIOC_GETTIMEOUT: 727 i = copy_to_user(argp, &timeout, sizeof(timeout)); 728 if (i) 729 return -EFAULT; 730 return 0; 731 732 case WDIOC_SET_PRETIMEOUT: 733 case WDIOC_SETPRETIMEOUT: 734 i = copy_from_user(&val, argp, sizeof(int)); 735 if (i) 736 return -EFAULT; 737 pretimeout = val; 738 return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); 739 740 case WDIOC_GET_PRETIMEOUT: 741 case WDIOC_GETPRETIMEOUT: 742 i = copy_to_user(argp, &pretimeout, sizeof(pretimeout)); 743 if (i) 744 return -EFAULT; 745 return 0; 746 747 case WDIOC_KEEPALIVE: 748 return ipmi_heartbeat(); 749 750 case WDIOC_SETOPTIONS: 751 i = copy_from_user(&val, argp, sizeof(int)); 752 if (i) 753 return -EFAULT; 754 if (val & WDIOS_DISABLECARD) { 755 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 756 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 757 ipmi_start_timer_on_heartbeat = 0; 758 } 759 760 if (val & WDIOS_ENABLECARD) { 761 ipmi_watchdog_state = action_val; 762 ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 763 } 764 return 0; 765 766 case WDIOC_GETSTATUS: 767 val = 0; 768 i = copy_to_user(argp, &val, sizeof(val)); 769 if (i) 770 return -EFAULT; 771 return 0; 772 773 default: 774 return -ENOIOCTLCMD; 775 } 776} 777 778static long ipmi_unlocked_ioctl(struct file *file, 779 unsigned int cmd, 780 unsigned long arg) 781{ 782 int ret; 783 784 mutex_lock(&ipmi_watchdog_mutex); 785 ret = ipmi_ioctl(file, cmd, arg); 786 mutex_unlock(&ipmi_watchdog_mutex); 787 788 return ret; 789} 790 791static ssize_t ipmi_write(struct file *file, 792 const char __user *buf, 793 size_t len, 794 loff_t *ppos) 795{ 796 int rv; 797 798 if (len) { 799 if (!nowayout) { 800 size_t i; 801 802 /* In case it was set long ago */ 803 expect_close = 0; 804 805 for (i = 0; i != len; i++) { 806 char c; 807 808 if (get_user(c, buf + i)) 809 return -EFAULT; 810 if (c == 'V') 811 expect_close = 42; 812 } 813 } 814 rv = ipmi_heartbeat(); 815 if (rv) 816 return rv; 817 } 818 return len; 819} 820 821static ssize_t ipmi_read(struct file *file, 822 char __user *buf, 823 size_t count, 824 loff_t *ppos) 825{ 826 int rv = 0; 827 wait_queue_t wait; 828 829 if (count <= 0) 830 return 0; 831 832 /* 833 * Reading returns if the pretimeout has gone off, and it only does 834 * it once per pretimeout. 835 */ 836 spin_lock(&ipmi_read_lock); 837 if (!data_to_read) { 838 if (file->f_flags & O_NONBLOCK) { 839 rv = -EAGAIN; 840 goto out; 841 } 842 843 init_waitqueue_entry(&wait, current); 844 add_wait_queue(&read_q, &wait); 845 while (!data_to_read) { 846 set_current_state(TASK_INTERRUPTIBLE); 847 spin_unlock(&ipmi_read_lock); 848 schedule(); 849 spin_lock(&ipmi_read_lock); 850 } 851 remove_wait_queue(&read_q, &wait); 852 853 if (signal_pending(current)) { 854 rv = -ERESTARTSYS; 855 goto out; 856 } 857 } 858 data_to_read = 0; 859 860 out: 861 spin_unlock(&ipmi_read_lock); 862 863 if (rv == 0) { 864 if (copy_to_user(buf, &data_to_read, 1)) 865 rv = -EFAULT; 866 else 867 rv = 1; 868 } 869 870 return rv; 871} 872 873static int ipmi_open(struct inode *ino, struct file *filep) 874{ 875 switch (iminor(ino)) { 876 case WATCHDOG_MINOR: 877 if (test_and_set_bit(0, &ipmi_wdog_open)) 878 return -EBUSY; 879 880 881 /* 882 * Don't start the timer now, let it start on the 883 * first heartbeat. 884 */ 885 ipmi_start_timer_on_heartbeat = 1; 886 return nonseekable_open(ino, filep); 887 888 default: 889 return (-ENODEV); 890 } 891} 892 893static unsigned int ipmi_poll(struct file *file, poll_table *wait) 894{ 895 unsigned int mask = 0; 896 897 poll_wait(file, &read_q, wait); 898 899 spin_lock(&ipmi_read_lock); 900 if (data_to_read) 901 mask |= (POLLIN | POLLRDNORM); 902 spin_unlock(&ipmi_read_lock); 903 904 return mask; 905} 906 907static int ipmi_fasync(int fd, struct file *file, int on) 908{ 909 int result; 910 911 result = fasync_helper(fd, file, on, &fasync_q); 912 913 return (result); 914} 915 916static int ipmi_close(struct inode *ino, struct file *filep) 917{ 918 if (iminor(ino) == WATCHDOG_MINOR) { 919 if (expect_close == 42) { 920 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 921 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 922 } else { 923 printk(KERN_CRIT PFX 924 "Unexpected close, not stopping watchdog!\n"); 925 ipmi_heartbeat(); 926 } 927 clear_bit(0, &ipmi_wdog_open); 928 } 929 930 expect_close = 0; 931 932 return 0; 933} 934 935static const struct file_operations ipmi_wdog_fops = { 936 .owner = THIS_MODULE, 937 .read = ipmi_read, 938 .poll = ipmi_poll, 939 .write = ipmi_write, 940 .unlocked_ioctl = ipmi_unlocked_ioctl, 941 .open = ipmi_open, 942 .release = ipmi_close, 943 .fasync = ipmi_fasync, 944 .llseek = no_llseek, 945}; 946 947static struct miscdevice ipmi_wdog_miscdev = { 948 .minor = WATCHDOG_MINOR, 949 .name = "watchdog", 950 .fops = &ipmi_wdog_fops 951}; 952 953static void ipmi_wdog_msg_handler(struct ipmi_recv_msg *msg, 954 void *handler_data) 955{ 956 if (msg->msg.cmd == IPMI_WDOG_RESET_TIMER && 957 msg->msg.data[0] == IPMI_WDOG_TIMER_NOT_INIT_RESP) 958 printk(KERN_INFO PFX "response: The IPMI controller appears" 959 " to have been reset, will attempt to reinitialize" 960 " the watchdog timer\n"); 961 else if (msg->msg.data[0] != 0) 962 printk(KERN_ERR PFX "response: Error %x on cmd %x\n", 963 msg->msg.data[0], 964 msg->msg.cmd); 965 966 ipmi_free_recv_msg(msg); 967} 968 969static void ipmi_wdog_pretimeout_handler(void *handler_data) 970{ 971 if (preaction_val != WDOG_PRETIMEOUT_NONE) { 972 if (preop_val == WDOG_PREOP_PANIC) { 973 if (atomic_inc_and_test(&preop_panic_excl)) 974 panic("Watchdog pre-timeout"); 975 } else if (preop_val == WDOG_PREOP_GIVE_DATA) { 976 spin_lock(&ipmi_read_lock); 977 data_to_read = 1; 978 wake_up_interruptible(&read_q); 979 kill_fasync(&fasync_q, SIGIO, POLL_IN); 980 981 spin_unlock(&ipmi_read_lock); 982 } 983 } 984 985 /* 986 * On some machines, the heartbeat will give an error and not 987 * work unless we re-enable the timer. So do so. 988 */ 989 pretimeout_since_last_heartbeat = 1; 990} 991 992static struct ipmi_user_hndl ipmi_hndlrs = { 993 .ipmi_recv_hndl = ipmi_wdog_msg_handler, 994 .ipmi_watchdog_pretimeout = ipmi_wdog_pretimeout_handler 995}; 996 997static void ipmi_register_watchdog(int ipmi_intf) 998{ 999 int rv = -EBUSY; 1000 1001 if (watchdog_user) 1002 goto out; 1003 1004 if ((ifnum_to_use >= 0) && (ifnum_to_use != ipmi_intf)) 1005 goto out; 1006 1007 watchdog_ifnum = ipmi_intf; 1008 1009 rv = ipmi_create_user(ipmi_intf, &ipmi_hndlrs, NULL, &watchdog_user); 1010 if (rv < 0) { 1011 printk(KERN_CRIT PFX "Unable to register with ipmi\n"); 1012 goto out; 1013 } 1014 1015 ipmi_get_version(watchdog_user, 1016 &ipmi_version_major, 1017 &ipmi_version_minor); 1018 1019 rv = misc_register(&ipmi_wdog_miscdev); 1020 if (rv < 0) { 1021 ipmi_destroy_user(watchdog_user); 1022 watchdog_user = NULL; 1023 printk(KERN_CRIT PFX "Unable to register misc device\n"); 1024 } 1025 1026#ifdef HAVE_DIE_NMI 1027 if (nmi_handler_registered) { 1028 int old_pretimeout = pretimeout; 1029 int old_timeout = timeout; 1030 int old_preop_val = preop_val; 1031 1032 /* 1033 * Set the pretimeout to go off in a second and give 1034 * ourselves plenty of time to stop the timer. 1035 */ 1036 ipmi_watchdog_state = WDOG_TIMEOUT_RESET; 1037 preop_val = WDOG_PREOP_NONE; /* Make sure nothing happens */ 1038 pretimeout = 99; 1039 timeout = 100; 1040 1041 testing_nmi = 1; 1042 1043 rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 1044 if (rv) { 1045 printk(KERN_WARNING PFX "Error starting timer to" 1046 " test NMI: 0x%x. The NMI pretimeout will" 1047 " likely not work\n", rv); 1048 rv = 0; 1049 goto out_restore; 1050 } 1051 1052 msleep(1500); 1053 1054 if (testing_nmi != 2) { 1055 printk(KERN_WARNING PFX "IPMI NMI didn't seem to" 1056 " occur. The NMI pretimeout will" 1057 " likely not work\n"); 1058 } 1059 out_restore: 1060 testing_nmi = 0; 1061 preop_val = old_preop_val; 1062 pretimeout = old_pretimeout; 1063 timeout = old_timeout; 1064 } 1065#endif 1066 1067 out: 1068 if ((start_now) && (rv == 0)) { 1069 /* Run from startup, so start the timer now. */ 1070 start_now = 0; /* Disable this function after first startup. */ 1071 ipmi_watchdog_state = action_val; 1072 ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB); 1073 printk(KERN_INFO PFX "Starting now!\n"); 1074 } else { 1075 /* Stop the timer now. */ 1076 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 1077 ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB); 1078 } 1079} 1080 1081static void ipmi_unregister_watchdog(int ipmi_intf) 1082{ 1083 int rv; 1084 1085 if (!watchdog_user) 1086 goto out; 1087 1088 if (watchdog_ifnum != ipmi_intf) 1089 goto out; 1090 1091 /* Make sure no one can call us any more. */ 1092 misc_deregister(&ipmi_wdog_miscdev); 1093 1094 /* 1095 * Wait to make sure the message makes it out. The lower layer has 1096 * pointers to our buffers, we want to make sure they are done before 1097 * we release our memory. 1098 */ 1099 while (atomic_read(&set_timeout_tofree)) 1100 schedule_timeout_uninterruptible(1); 1101 1102 /* Disconnect from IPMI. */ 1103 rv = ipmi_destroy_user(watchdog_user); 1104 if (rv) { 1105 printk(KERN_WARNING PFX "error unlinking from IPMI: %d\n", 1106 rv); 1107 } 1108 watchdog_user = NULL; 1109 1110 out: 1111 return; 1112} 1113 1114#ifdef HAVE_DIE_NMI 1115static int 1116ipmi_nmi(unsigned int val, struct pt_regs *regs) 1117{ 1118 /* 1119 * If we get here, it's an NMI that's not a memory or I/O 1120 * error. We can't truly tell if it's from IPMI or not 1121 * without sending a message, and sending a message is almost 1122 * impossible because of locking. 1123 */ 1124 1125 if (testing_nmi) { 1126 testing_nmi = 2; 1127 return NMI_HANDLED; 1128 } 1129 1130 /* If we are not expecting a timeout, ignore it. */ 1131 if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) 1132 return NMI_DONE; 1133 1134 if (preaction_val != WDOG_PRETIMEOUT_NMI) 1135 return NMI_DONE; 1136 1137 /* 1138 * If no one else handled the NMI, we assume it was the IPMI 1139 * watchdog. 1140 */ 1141 if (preop_val == WDOG_PREOP_PANIC) { 1142 /* On some machines, the heartbeat will give 1143 an error and not work unless we re-enable 1144 the timer. So do so. */ 1145 pretimeout_since_last_heartbeat = 1; 1146 if (atomic_inc_and_test(&preop_panic_excl)) 1147 panic(PFX "pre-timeout"); 1148 } 1149 1150 return NMI_HANDLED; 1151} 1152#endif 1153 1154static int wdog_reboot_handler(struct notifier_block *this, 1155 unsigned long code, 1156 void *unused) 1157{ 1158 static int reboot_event_handled; 1159 1160 if ((watchdog_user) && (!reboot_event_handled)) { 1161 /* Make sure we only do this once. */ 1162 reboot_event_handled = 1; 1163 1164 if (code == SYS_POWER_OFF || code == SYS_HALT) { 1165 /* Disable the WDT if we are shutting down. */ 1166 ipmi_watchdog_state = WDOG_TIMEOUT_NONE; 1167 panic_halt_ipmi_set_timeout(); 1168 } else if (ipmi_watchdog_state != WDOG_TIMEOUT_NONE) { 1169 /* Set a long timer to let the reboot happens, but 1170 reboot if it hangs, but only if the watchdog 1171 timer was already running. */ 1172 timeout = 120; 1173 pretimeout = 0; 1174 ipmi_watchdog_state = WDOG_TIMEOUT_RESET; 1175 panic_halt_ipmi_set_timeout(); 1176 } 1177 } 1178 return NOTIFY_OK; 1179} 1180 1181static struct notifier_block wdog_reboot_notifier = { 1182 .notifier_call = wdog_reboot_handler, 1183 .next = NULL, 1184 .priority = 0 1185}; 1186 1187static int wdog_panic_handler(struct notifier_block *this, 1188 unsigned long event, 1189 void *unused) 1190{ 1191 static int panic_event_handled; 1192 1193 /* On a panic, if we have a panic timeout, make sure to extend 1194 the watchdog timer to a reasonable value to complete the 1195 panic, if the watchdog timer is running. Plus the 1196 pretimeout is meaningless at panic time. */ 1197 if (watchdog_user && !panic_event_handled && 1198 ipmi_watchdog_state != WDOG_TIMEOUT_NONE) { 1199 /* Make sure we do this only once. */ 1200 panic_event_handled = 1; 1201 1202 timeout = 255; 1203 pretimeout = 0; 1204 panic_halt_ipmi_set_timeout(); 1205 } 1206 1207 return NOTIFY_OK; 1208} 1209 1210static struct notifier_block wdog_panic_notifier = { 1211 .notifier_call = wdog_panic_handler, 1212 .next = NULL, 1213 .priority = 150 /* priority: INT_MAX >= x >= 0 */ 1214}; 1215 1216 1217static void ipmi_new_smi(int if_num, struct device *device) 1218{ 1219 ipmi_register_watchdog(if_num); 1220} 1221 1222static void ipmi_smi_gone(int if_num) 1223{ 1224 ipmi_unregister_watchdog(if_num); 1225} 1226 1227static struct ipmi_smi_watcher smi_watcher = { 1228 .owner = THIS_MODULE, 1229 .new_smi = ipmi_new_smi, 1230 .smi_gone = ipmi_smi_gone 1231}; 1232 1233static int action_op(const char *inval, char *outval) 1234{ 1235 if (outval) 1236 strcpy(outval, action); 1237 1238 if (!inval) 1239 return 0; 1240 1241 if (strcmp(inval, "reset") == 0) 1242 action_val = WDOG_TIMEOUT_RESET; 1243 else if (strcmp(inval, "none") == 0) 1244 action_val = WDOG_TIMEOUT_NONE; 1245 else if (strcmp(inval, "power_cycle") == 0) 1246 action_val = WDOG_TIMEOUT_POWER_CYCLE; 1247 else if (strcmp(inval, "power_off") == 0) 1248 action_val = WDOG_TIMEOUT_POWER_DOWN; 1249 else 1250 return -EINVAL; 1251 strcpy(action, inval); 1252 return 0; 1253} 1254 1255static int preaction_op(const char *inval, char *outval) 1256{ 1257 if (outval) 1258 strcpy(outval, preaction); 1259 1260 if (!inval) 1261 return 0; 1262 1263 if (strcmp(inval, "pre_none") == 0) 1264 preaction_val = WDOG_PRETIMEOUT_NONE; 1265 else if (strcmp(inval, "pre_smi") == 0) 1266 preaction_val = WDOG_PRETIMEOUT_SMI; 1267#ifdef HAVE_DIE_NMI 1268 else if (strcmp(inval, "pre_nmi") == 0) 1269 preaction_val = WDOG_PRETIMEOUT_NMI; 1270#endif 1271 else if (strcmp(inval, "pre_int") == 0) 1272 preaction_val = WDOG_PRETIMEOUT_MSG_INT; 1273 else 1274 return -EINVAL; 1275 strcpy(preaction, inval); 1276 return 0; 1277} 1278 1279static int preop_op(const char *inval, char *outval) 1280{ 1281 if (outval) 1282 strcpy(outval, preop); 1283 1284 if (!inval) 1285 return 0; 1286 1287 if (strcmp(inval, "preop_none") == 0) 1288 preop_val = WDOG_PREOP_NONE; 1289 else if (strcmp(inval, "preop_panic") == 0) 1290 preop_val = WDOG_PREOP_PANIC; 1291 else if (strcmp(inval, "preop_give_data") == 0) 1292 preop_val = WDOG_PREOP_GIVE_DATA; 1293 else 1294 return -EINVAL; 1295 strcpy(preop, inval); 1296 return 0; 1297} 1298 1299static void check_parms(void) 1300{ 1301#ifdef HAVE_DIE_NMI 1302 int do_nmi = 0; 1303 int rv; 1304 1305 if (preaction_val == WDOG_PRETIMEOUT_NMI) { 1306 do_nmi = 1; 1307 if (preop_val == WDOG_PREOP_GIVE_DATA) { 1308 printk(KERN_WARNING PFX "Pretimeout op is to give data" 1309 " but NMI pretimeout is enabled, setting" 1310 " pretimeout op to none\n"); 1311 preop_op("preop_none", NULL); 1312 do_nmi = 0; 1313 } 1314 } 1315 if (do_nmi && !nmi_handler_registered) { 1316 rv = register_nmi_handler(NMI_UNKNOWN, ipmi_nmi, 0, 1317 "ipmi"); 1318 if (rv) { 1319 printk(KERN_WARNING PFX 1320 "Can't register nmi handler\n"); 1321 return; 1322 } else 1323 nmi_handler_registered = 1; 1324 } else if (!do_nmi && nmi_handler_registered) { 1325 unregister_nmi_handler(NMI_UNKNOWN, "ipmi"); 1326 nmi_handler_registered = 0; 1327 } 1328#endif 1329} 1330 1331static int __init ipmi_wdog_init(void) 1332{ 1333 int rv; 1334 1335 if (action_op(action, NULL)) { 1336 action_op("reset", NULL); 1337 printk(KERN_INFO PFX "Unknown action '%s', defaulting to" 1338 " reset\n", action); 1339 } 1340 1341 if (preaction_op(preaction, NULL)) { 1342 preaction_op("pre_none", NULL); 1343 printk(KERN_INFO PFX "Unknown preaction '%s', defaulting to" 1344 " none\n", preaction); 1345 } 1346 1347 if (preop_op(preop, NULL)) { 1348 preop_op("preop_none", NULL); 1349 printk(KERN_INFO PFX "Unknown preop '%s', defaulting to" 1350 " none\n", preop); 1351 } 1352 1353 check_parms(); 1354 1355 register_reboot_notifier(&wdog_reboot_notifier); 1356 atomic_notifier_chain_register(&panic_notifier_list, 1357 &wdog_panic_notifier); 1358 1359 rv = ipmi_smi_watcher_register(&smi_watcher); 1360 if (rv) { 1361#ifdef HAVE_DIE_NMI 1362 if (nmi_handler_registered) 1363 unregister_nmi_handler(NMI_UNKNOWN, "ipmi"); 1364#endif 1365 atomic_notifier_chain_unregister(&panic_notifier_list, 1366 &wdog_panic_notifier); 1367 unregister_reboot_notifier(&wdog_reboot_notifier); 1368 printk(KERN_WARNING PFX "can't register smi watcher\n"); 1369 return rv; 1370 } 1371 1372 printk(KERN_INFO PFX "driver initialized\n"); 1373 1374 return 0; 1375} 1376 1377static void __exit ipmi_wdog_exit(void) 1378{ 1379 ipmi_smi_watcher_unregister(&smi_watcher); 1380 ipmi_unregister_watchdog(watchdog_ifnum); 1381 1382#ifdef HAVE_DIE_NMI 1383 if (nmi_handler_registered) 1384 unregister_nmi_handler(NMI_UNKNOWN, "ipmi"); 1385#endif 1386 1387 atomic_notifier_chain_unregister(&panic_notifier_list, 1388 &wdog_panic_notifier); 1389 unregister_reboot_notifier(&wdog_reboot_notifier); 1390} 1391module_exit(ipmi_wdog_exit); 1392module_init(ipmi_wdog_init); 1393MODULE_LICENSE("GPL"); 1394MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>"); 1395MODULE_DESCRIPTION("watchdog timer based upon the IPMI interface."); 1396