Path: blob/master/drivers/char/ipmi/ipmi_poweroff.c
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/*1* ipmi_poweroff.c2*3* MontaVista IPMI Poweroff extension to sys_reboot4*5* Author: MontaVista Software, Inc.6* Steven Dake <[email protected]>7* Corey Minyard <[email protected]>8* [email protected]9*10* Copyright 2002,2004 MontaVista Software Inc.11*12* This program is free software; you can redistribute it and/or modify it13* under the terms of the GNU General Public License as published by the14* Free Software Foundation; either version 2 of the License, or (at your15* option) any later version.16*17*18* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED19* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF20* 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; LOSS24* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND25* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR26* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE27* 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 along30* with this program; if not, write to the Free Software Foundation, Inc.,31* 675 Mass Ave, Cambridge, MA 02139, USA.32*/33#include <linux/module.h>34#include <linux/moduleparam.h>35#include <linux/proc_fs.h>36#include <linux/string.h>37#include <linux/completion.h>38#include <linux/pm.h>39#include <linux/kdev_t.h>40#include <linux/ipmi.h>41#include <linux/ipmi_smi.h>4243#define PFX "IPMI poweroff: "4445static void ipmi_po_smi_gone(int if_num);46static void ipmi_po_new_smi(int if_num, struct device *device);4748/* Definitions for controlling power off (if the system supports it). It49* conveniently matches the IPMI chassis control values. */50#define IPMI_CHASSIS_POWER_DOWN 0 /* power down, the default. */51#define IPMI_CHASSIS_POWER_CYCLE 0x02 /* power cycle */5253/* the IPMI data command */54static int poweroff_powercycle;5556/* Which interface to use, -1 means the first we see. */57static int ifnum_to_use = -1;5859/* Our local state. */60static int ready;61static ipmi_user_t ipmi_user;62static int ipmi_ifnum;63static void (*specific_poweroff_func)(ipmi_user_t user);6465/* Holds the old poweroff function so we can restore it on removal. */66static void (*old_poweroff_func)(void);6768static int set_param_ifnum(const char *val, struct kernel_param *kp)69{70int rv = param_set_int(val, kp);71if (rv)72return rv;73if ((ifnum_to_use < 0) || (ifnum_to_use == ipmi_ifnum))74return 0;7576ipmi_po_smi_gone(ipmi_ifnum);77ipmi_po_new_smi(ifnum_to_use, NULL);78return 0;79}8081module_param_call(ifnum_to_use, set_param_ifnum, param_get_int,82&ifnum_to_use, 0644);83MODULE_PARM_DESC(ifnum_to_use, "The interface number to use for the watchdog "84"timer. Setting to -1 defaults to the first registered "85"interface");8687/* parameter definition to allow user to flag power cycle */88module_param(poweroff_powercycle, int, 0644);89MODULE_PARM_DESC(poweroff_powercycle,90" Set to non-zero to enable power cycle instead of power"91" down. Power cycle is contingent on hardware support,"92" otherwise it defaults back to power down.");9394/* Stuff from the get device id command. */95static unsigned int mfg_id;96static unsigned int prod_id;97static unsigned char capabilities;98static unsigned char ipmi_version;99100/*101* We use our own messages for this operation, we don't let the system102* allocate them, since we may be in a panic situation. The whole103* thing is single-threaded, anyway, so multiple messages are not104* required.105*/106static atomic_t dummy_count = ATOMIC_INIT(0);107static void dummy_smi_free(struct ipmi_smi_msg *msg)108{109atomic_dec(&dummy_count);110}111static void dummy_recv_free(struct ipmi_recv_msg *msg)112{113atomic_dec(&dummy_count);114}115static struct ipmi_smi_msg halt_smi_msg = {116.done = dummy_smi_free117};118static struct ipmi_recv_msg halt_recv_msg = {119.done = dummy_recv_free120};121122123/*124* Code to send a message and wait for the response.125*/126127static void receive_handler(struct ipmi_recv_msg *recv_msg, void *handler_data)128{129struct completion *comp = recv_msg->user_msg_data;130131if (comp)132complete(comp);133}134135static struct ipmi_user_hndl ipmi_poweroff_handler = {136.ipmi_recv_hndl = receive_handler137};138139140static int ipmi_request_wait_for_response(ipmi_user_t user,141struct ipmi_addr *addr,142struct kernel_ipmi_msg *send_msg)143{144int rv;145struct completion comp;146147init_completion(&comp);148149rv = ipmi_request_supply_msgs(user, addr, 0, send_msg, &comp,150&halt_smi_msg, &halt_recv_msg, 0);151if (rv)152return rv;153154wait_for_completion(&comp);155156return halt_recv_msg.msg.data[0];157}158159/* Wait for message to complete, spinning. */160static int ipmi_request_in_rc_mode(ipmi_user_t user,161struct ipmi_addr *addr,162struct kernel_ipmi_msg *send_msg)163{164int rv;165166atomic_set(&dummy_count, 2);167rv = ipmi_request_supply_msgs(user, addr, 0, send_msg, NULL,168&halt_smi_msg, &halt_recv_msg, 0);169if (rv) {170atomic_set(&dummy_count, 0);171return rv;172}173174/*175* Spin until our message is done.176*/177while (atomic_read(&dummy_count) > 0) {178ipmi_poll_interface(user);179cpu_relax();180}181182return halt_recv_msg.msg.data[0];183}184185/*186* ATCA Support187*/188189#define IPMI_NETFN_ATCA 0x2c190#define IPMI_ATCA_SET_POWER_CMD 0x11191#define IPMI_ATCA_GET_ADDR_INFO_CMD 0x01192#define IPMI_PICMG_ID 0193194#define IPMI_NETFN_OEM 0x2e195#define IPMI_ATCA_PPS_GRACEFUL_RESTART 0x11196#define IPMI_ATCA_PPS_IANA "\x00\x40\x0A"197#define IPMI_MOTOROLA_MANUFACTURER_ID 0x0000A1198#define IPMI_MOTOROLA_PPS_IPMC_PRODUCT_ID 0x0051199200static void (*atca_oem_poweroff_hook)(ipmi_user_t user);201202static void pps_poweroff_atca(ipmi_user_t user)203{204struct ipmi_system_interface_addr smi_addr;205struct kernel_ipmi_msg send_msg;206int rv;207/*208* Configure IPMI address for local access209*/210smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;211smi_addr.channel = IPMI_BMC_CHANNEL;212smi_addr.lun = 0;213214printk(KERN_INFO PFX "PPS powerdown hook used");215216send_msg.netfn = IPMI_NETFN_OEM;217send_msg.cmd = IPMI_ATCA_PPS_GRACEFUL_RESTART;218send_msg.data = IPMI_ATCA_PPS_IANA;219send_msg.data_len = 3;220rv = ipmi_request_in_rc_mode(user,221(struct ipmi_addr *) &smi_addr,222&send_msg);223if (rv && rv != IPMI_UNKNOWN_ERR_COMPLETION_CODE) {224printk(KERN_ERR PFX "Unable to send ATCA ,"225" IPMI error 0x%x\n", rv);226}227return;228}229230static int ipmi_atca_detect(ipmi_user_t user)231{232struct ipmi_system_interface_addr smi_addr;233struct kernel_ipmi_msg send_msg;234int rv;235unsigned char data[1];236237/*238* Configure IPMI address for local access239*/240smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;241smi_addr.channel = IPMI_BMC_CHANNEL;242smi_addr.lun = 0;243244/*245* Use get address info to check and see if we are ATCA246*/247send_msg.netfn = IPMI_NETFN_ATCA;248send_msg.cmd = IPMI_ATCA_GET_ADDR_INFO_CMD;249data[0] = IPMI_PICMG_ID;250send_msg.data = data;251send_msg.data_len = sizeof(data);252rv = ipmi_request_wait_for_response(user,253(struct ipmi_addr *) &smi_addr,254&send_msg);255256printk(KERN_INFO PFX "ATCA Detect mfg 0x%X prod 0x%X\n",257mfg_id, prod_id);258if ((mfg_id == IPMI_MOTOROLA_MANUFACTURER_ID)259&& (prod_id == IPMI_MOTOROLA_PPS_IPMC_PRODUCT_ID)) {260printk(KERN_INFO PFX261"Installing Pigeon Point Systems Poweroff Hook\n");262atca_oem_poweroff_hook = pps_poweroff_atca;263}264return !rv;265}266267static void ipmi_poweroff_atca(ipmi_user_t user)268{269struct ipmi_system_interface_addr smi_addr;270struct kernel_ipmi_msg send_msg;271int rv;272unsigned char data[4];273274/*275* Configure IPMI address for local access276*/277smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;278smi_addr.channel = IPMI_BMC_CHANNEL;279smi_addr.lun = 0;280281printk(KERN_INFO PFX "Powering down via ATCA power command\n");282283/*284* Power down285*/286send_msg.netfn = IPMI_NETFN_ATCA;287send_msg.cmd = IPMI_ATCA_SET_POWER_CMD;288data[0] = IPMI_PICMG_ID;289data[1] = 0; /* FRU id */290data[2] = 0; /* Power Level */291data[3] = 0; /* Don't change saved presets */292send_msg.data = data;293send_msg.data_len = sizeof(data);294rv = ipmi_request_in_rc_mode(user,295(struct ipmi_addr *) &smi_addr,296&send_msg);297/*298* At this point, the system may be shutting down, and most299* serial drivers (if used) will have interrupts turned off300* it may be better to ignore IPMI_UNKNOWN_ERR_COMPLETION_CODE301* return code302*/303if (rv && rv != IPMI_UNKNOWN_ERR_COMPLETION_CODE) {304printk(KERN_ERR PFX "Unable to send ATCA powerdown message,"305" IPMI error 0x%x\n", rv);306goto out;307}308309if (atca_oem_poweroff_hook)310atca_oem_poweroff_hook(user);311out:312return;313}314315/*316* CPI1 Support317*/318319#define IPMI_NETFN_OEM_1 0xf8320#define OEM_GRP_CMD_SET_RESET_STATE 0x84321#define OEM_GRP_CMD_SET_POWER_STATE 0x82322#define IPMI_NETFN_OEM_8 0xf8323#define OEM_GRP_CMD_REQUEST_HOTSWAP_CTRL 0x80324#define OEM_GRP_CMD_GET_SLOT_GA 0xa3325#define IPMI_NETFN_SENSOR_EVT 0x10326#define IPMI_CMD_GET_EVENT_RECEIVER 0x01327328#define IPMI_CPI1_PRODUCT_ID 0x000157329#define IPMI_CPI1_MANUFACTURER_ID 0x0108330331static int ipmi_cpi1_detect(ipmi_user_t user)332{333return ((mfg_id == IPMI_CPI1_MANUFACTURER_ID)334&& (prod_id == IPMI_CPI1_PRODUCT_ID));335}336337static void ipmi_poweroff_cpi1(ipmi_user_t user)338{339struct ipmi_system_interface_addr smi_addr;340struct ipmi_ipmb_addr ipmb_addr;341struct kernel_ipmi_msg send_msg;342int rv;343unsigned char data[1];344int slot;345unsigned char hotswap_ipmb;346unsigned char aer_addr;347unsigned char aer_lun;348349/*350* Configure IPMI address for local access351*/352smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;353smi_addr.channel = IPMI_BMC_CHANNEL;354smi_addr.lun = 0;355356printk(KERN_INFO PFX "Powering down via CPI1 power command\n");357358/*359* Get IPMI ipmb address360*/361send_msg.netfn = IPMI_NETFN_OEM_8 >> 2;362send_msg.cmd = OEM_GRP_CMD_GET_SLOT_GA;363send_msg.data = NULL;364send_msg.data_len = 0;365rv = ipmi_request_in_rc_mode(user,366(struct ipmi_addr *) &smi_addr,367&send_msg);368if (rv)369goto out;370slot = halt_recv_msg.msg.data[1];371hotswap_ipmb = (slot > 9) ? (0xb0 + 2 * slot) : (0xae + 2 * slot);372373/*374* Get active event receiver375*/376send_msg.netfn = IPMI_NETFN_SENSOR_EVT >> 2;377send_msg.cmd = IPMI_CMD_GET_EVENT_RECEIVER;378send_msg.data = NULL;379send_msg.data_len = 0;380rv = ipmi_request_in_rc_mode(user,381(struct ipmi_addr *) &smi_addr,382&send_msg);383if (rv)384goto out;385aer_addr = halt_recv_msg.msg.data[1];386aer_lun = halt_recv_msg.msg.data[2];387388/*389* Setup IPMB address target instead of local target390*/391ipmb_addr.addr_type = IPMI_IPMB_ADDR_TYPE;392ipmb_addr.channel = 0;393ipmb_addr.slave_addr = aer_addr;394ipmb_addr.lun = aer_lun;395396/*397* Send request hotswap control to remove blade from dpv398*/399send_msg.netfn = IPMI_NETFN_OEM_8 >> 2;400send_msg.cmd = OEM_GRP_CMD_REQUEST_HOTSWAP_CTRL;401send_msg.data = &hotswap_ipmb;402send_msg.data_len = 1;403ipmi_request_in_rc_mode(user,404(struct ipmi_addr *) &ipmb_addr,405&send_msg);406407/*408* Set reset asserted409*/410send_msg.netfn = IPMI_NETFN_OEM_1 >> 2;411send_msg.cmd = OEM_GRP_CMD_SET_RESET_STATE;412send_msg.data = data;413data[0] = 1; /* Reset asserted state */414send_msg.data_len = 1;415rv = ipmi_request_in_rc_mode(user,416(struct ipmi_addr *) &smi_addr,417&send_msg);418if (rv)419goto out;420421/*422* Power down423*/424send_msg.netfn = IPMI_NETFN_OEM_1 >> 2;425send_msg.cmd = OEM_GRP_CMD_SET_POWER_STATE;426send_msg.data = data;427data[0] = 1; /* Power down state */428send_msg.data_len = 1;429rv = ipmi_request_in_rc_mode(user,430(struct ipmi_addr *) &smi_addr,431&send_msg);432if (rv)433goto out;434435out:436return;437}438439/*440* ipmi_dell_chassis_detect()441* Dell systems with IPMI < 1.5 don't set the chassis capability bit442* but they can handle a chassis poweroff or powercycle command.443*/444445#define DELL_IANA_MFR_ID {0xA2, 0x02, 0x00}446static int ipmi_dell_chassis_detect(ipmi_user_t user)447{448const char ipmi_version_major = ipmi_version & 0xF;449const char ipmi_version_minor = (ipmi_version >> 4) & 0xF;450const char mfr[3] = DELL_IANA_MFR_ID;451if (!memcmp(mfr, &mfg_id, sizeof(mfr)) &&452ipmi_version_major <= 1 &&453ipmi_version_minor < 5)454return 1;455return 0;456}457458/*459* Standard chassis support460*/461462#define IPMI_NETFN_CHASSIS_REQUEST 0463#define IPMI_CHASSIS_CONTROL_CMD 0x02464465static int ipmi_chassis_detect(ipmi_user_t user)466{467/* Chassis support, use it. */468return (capabilities & 0x80);469}470471static void ipmi_poweroff_chassis(ipmi_user_t user)472{473struct ipmi_system_interface_addr smi_addr;474struct kernel_ipmi_msg send_msg;475int rv;476unsigned char data[1];477478/*479* Configure IPMI address for local access480*/481smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;482smi_addr.channel = IPMI_BMC_CHANNEL;483smi_addr.lun = 0;484485powercyclefailed:486printk(KERN_INFO PFX "Powering %s via IPMI chassis control command\n",487(poweroff_powercycle ? "cycle" : "down"));488489/*490* Power down491*/492send_msg.netfn = IPMI_NETFN_CHASSIS_REQUEST;493send_msg.cmd = IPMI_CHASSIS_CONTROL_CMD;494if (poweroff_powercycle)495data[0] = IPMI_CHASSIS_POWER_CYCLE;496else497data[0] = IPMI_CHASSIS_POWER_DOWN;498send_msg.data = data;499send_msg.data_len = sizeof(data);500rv = ipmi_request_in_rc_mode(user,501(struct ipmi_addr *) &smi_addr,502&send_msg);503if (rv) {504if (poweroff_powercycle) {505/* power cycle failed, default to power down */506printk(KERN_ERR PFX "Unable to send chassis power " \507"cycle message, IPMI error 0x%x\n", rv);508poweroff_powercycle = 0;509goto powercyclefailed;510}511512printk(KERN_ERR PFX "Unable to send chassis power " \513"down message, IPMI error 0x%x\n", rv);514}515}516517518/* Table of possible power off functions. */519struct poweroff_function {520char *platform_type;521int (*detect)(ipmi_user_t user);522void (*poweroff_func)(ipmi_user_t user);523};524525static struct poweroff_function poweroff_functions[] = {526{ .platform_type = "ATCA",527.detect = ipmi_atca_detect,528.poweroff_func = ipmi_poweroff_atca },529{ .platform_type = "CPI1",530.detect = ipmi_cpi1_detect,531.poweroff_func = ipmi_poweroff_cpi1 },532{ .platform_type = "chassis",533.detect = ipmi_dell_chassis_detect,534.poweroff_func = ipmi_poweroff_chassis },535/* Chassis should generally be last, other things should override536it. */537{ .platform_type = "chassis",538.detect = ipmi_chassis_detect,539.poweroff_func = ipmi_poweroff_chassis },540};541#define NUM_PO_FUNCS (sizeof(poweroff_functions) \542/ sizeof(struct poweroff_function))543544545/* Called on a powerdown request. */546static void ipmi_poweroff_function(void)547{548if (!ready)549return;550551/* Use run-to-completion mode, since interrupts may be off. */552specific_poweroff_func(ipmi_user);553}554555/* Wait for an IPMI interface to be installed, the first one installed556will be grabbed by this code and used to perform the powerdown. */557static void ipmi_po_new_smi(int if_num, struct device *device)558{559struct ipmi_system_interface_addr smi_addr;560struct kernel_ipmi_msg send_msg;561int rv;562int i;563564if (ready)565return;566567if ((ifnum_to_use >= 0) && (ifnum_to_use != if_num))568return;569570rv = ipmi_create_user(if_num, &ipmi_poweroff_handler, NULL,571&ipmi_user);572if (rv) {573printk(KERN_ERR PFX "could not create IPMI user, error %d\n",574rv);575return;576}577578ipmi_ifnum = if_num;579580/*581* Do a get device ide and store some results, since this is582* used by several functions.583*/584smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;585smi_addr.channel = IPMI_BMC_CHANNEL;586smi_addr.lun = 0;587588send_msg.netfn = IPMI_NETFN_APP_REQUEST;589send_msg.cmd = IPMI_GET_DEVICE_ID_CMD;590send_msg.data = NULL;591send_msg.data_len = 0;592rv = ipmi_request_wait_for_response(ipmi_user,593(struct ipmi_addr *) &smi_addr,594&send_msg);595if (rv) {596printk(KERN_ERR PFX "Unable to send IPMI get device id info,"597" IPMI error 0x%x\n", rv);598goto out_err;599}600601if (halt_recv_msg.msg.data_len < 12) {602printk(KERN_ERR PFX "(chassis) IPMI get device id info too,"603" short, was %d bytes, needed %d bytes\n",604halt_recv_msg.msg.data_len, 12);605goto out_err;606}607608mfg_id = (halt_recv_msg.msg.data[7]609| (halt_recv_msg.msg.data[8] << 8)610| (halt_recv_msg.msg.data[9] << 16));611prod_id = (halt_recv_msg.msg.data[10]612| (halt_recv_msg.msg.data[11] << 8));613capabilities = halt_recv_msg.msg.data[6];614ipmi_version = halt_recv_msg.msg.data[5];615616617/* Scan for a poweroff method */618for (i = 0; i < NUM_PO_FUNCS; i++) {619if (poweroff_functions[i].detect(ipmi_user))620goto found;621}622623out_err:624printk(KERN_ERR PFX "Unable to find a poweroff function that"625" will work, giving up\n");626ipmi_destroy_user(ipmi_user);627return;628629found:630printk(KERN_INFO PFX "Found a %s style poweroff function\n",631poweroff_functions[i].platform_type);632specific_poweroff_func = poweroff_functions[i].poweroff_func;633old_poweroff_func = pm_power_off;634pm_power_off = ipmi_poweroff_function;635ready = 1;636}637638static void ipmi_po_smi_gone(int if_num)639{640if (!ready)641return;642643if (ipmi_ifnum != if_num)644return;645646ready = 0;647ipmi_destroy_user(ipmi_user);648pm_power_off = old_poweroff_func;649}650651static struct ipmi_smi_watcher smi_watcher = {652.owner = THIS_MODULE,653.new_smi = ipmi_po_new_smi,654.smi_gone = ipmi_po_smi_gone655};656657658#ifdef CONFIG_PROC_FS659#include <linux/sysctl.h>660661static ctl_table ipmi_table[] = {662{ .procname = "poweroff_powercycle",663.data = &poweroff_powercycle,664.maxlen = sizeof(poweroff_powercycle),665.mode = 0644,666.proc_handler = proc_dointvec },667{ }668};669670static ctl_table ipmi_dir_table[] = {671{ .procname = "ipmi",672.mode = 0555,673.child = ipmi_table },674{ }675};676677static ctl_table ipmi_root_table[] = {678{ .procname = "dev",679.mode = 0555,680.child = ipmi_dir_table },681{ }682};683684static struct ctl_table_header *ipmi_table_header;685#endif /* CONFIG_PROC_FS */686687/*688* Startup and shutdown functions.689*/690static int __init ipmi_poweroff_init(void)691{692int rv;693694printk(KERN_INFO "Copyright (C) 2004 MontaVista Software -"695" IPMI Powerdown via sys_reboot.\n");696697if (poweroff_powercycle)698printk(KERN_INFO PFX "Power cycle is enabled.\n");699700#ifdef CONFIG_PROC_FS701ipmi_table_header = register_sysctl_table(ipmi_root_table);702if (!ipmi_table_header) {703printk(KERN_ERR PFX "Unable to register powercycle sysctl\n");704rv = -ENOMEM;705goto out_err;706}707#endif708709rv = ipmi_smi_watcher_register(&smi_watcher);710711#ifdef CONFIG_PROC_FS712if (rv) {713unregister_sysctl_table(ipmi_table_header);714printk(KERN_ERR PFX "Unable to register SMI watcher: %d\n", rv);715goto out_err;716}717718out_err:719#endif720return rv;721}722723#ifdef MODULE724static void __exit ipmi_poweroff_cleanup(void)725{726int rv;727728#ifdef CONFIG_PROC_FS729unregister_sysctl_table(ipmi_table_header);730#endif731732ipmi_smi_watcher_unregister(&smi_watcher);733734if (ready) {735rv = ipmi_destroy_user(ipmi_user);736if (rv)737printk(KERN_ERR PFX "could not cleanup the IPMI"738" user: 0x%x\n", rv);739pm_power_off = old_poweroff_func;740}741}742module_exit(ipmi_poweroff_cleanup);743#endif744745module_init(ipmi_poweroff_init);746MODULE_LICENSE("GPL");747MODULE_AUTHOR("Corey Minyard <[email protected]>");748MODULE_DESCRIPTION("IPMI Poweroff extension to sys_reboot");749750751