From 895dcfd1cab84d7e1c22af645a7f2f3c9bb5f24e Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Wed, 28 Mar 2012 14:42:49 -0700 Subject: [PATCH] ipmi: fix message handling during panics The part of the IPMI driver that delivered panic information to the event log and extended the watchdog timeout during a panic was not properly handling the messages. It used static messages to avoid allocation, but wasn't properly waiting for these, or wasn't properly handling the refcounts. Signed-off-by: Corey Minyard Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/char/ipmi/ipmi_msghandler.c | 103 +++++++++++++--------------- drivers/char/ipmi/ipmi_watchdog.c | 17 +++-- 2 files changed, 56 insertions(+), 64 deletions(-) diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index 289ab506b79b..5c1820c2a853 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -2794,16 +2794,18 @@ channel_handler(ipmi_smi_t intf, struct ipmi_recv_msg *msg) return; } -void ipmi_poll_interface(ipmi_user_t user) +static void ipmi_poll(ipmi_smi_t intf) { - ipmi_smi_t intf = user->intf; - if (intf->handlers->poll) intf->handlers->poll(intf->send_info); - /* In case something came in */ handle_new_recv_msgs(intf); } + +void ipmi_poll_interface(ipmi_user_t user) +{ + ipmi_poll(user->intf); +} EXPORT_SYMBOL(ipmi_poll_interface); int ipmi_register_smi(struct ipmi_smi_handlers *handlers, @@ -4204,12 +4206,48 @@ EXPORT_SYMBOL(ipmi_free_recv_msg); #ifdef CONFIG_IPMI_PANIC_EVENT +static atomic_t panic_done_count = ATOMIC_INIT(0); + static void dummy_smi_done_handler(struct ipmi_smi_msg *msg) { + atomic_dec(&panic_done_count); } static void dummy_recv_done_handler(struct ipmi_recv_msg *msg) { + atomic_dec(&panic_done_count); +} + +/* + * Inside a panic, send a message and wait for a response. + */ +static void ipmi_panic_request_and_wait(ipmi_smi_t intf, + struct ipmi_addr *addr, + struct kernel_ipmi_msg *msg) +{ + struct ipmi_smi_msg smi_msg; + struct ipmi_recv_msg recv_msg; + int rv; + + smi_msg.done = dummy_smi_done_handler; + recv_msg.done = dummy_recv_done_handler; + atomic_add(2, &panic_done_count); + rv = i_ipmi_request(NULL, + intf, + addr, + 0, + msg, + intf, + &smi_msg, + &recv_msg, + 0, + intf->channels[0].address, + intf->channels[0].lun, + 0, 1); /* Don't retry, and don't wait. */ + if (rv) + atomic_sub(2, &panic_done_count); + while (atomic_read(&panic_done_count) != 0) + ipmi_poll(intf); } #ifdef CONFIG_IPMI_PANIC_STRING @@ -4248,8 +4286,6 @@ static void send_panic_events(char *str) unsigned char data[16]; struct ipmi_system_interface_addr *si; struct ipmi_addr addr; - struct ipmi_smi_msg smi_msg; - struct ipmi_recv_msg recv_msg; si = (struct ipmi_system_interface_addr *) &addr; si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE; @@ -4277,9 +4313,6 @@ static void send_panic_events(char *str) data[7] = str[2]; } - smi_msg.done = dummy_smi_done_handler; - recv_msg.done = dummy_recv_done_handler; - /* For every registered interface, send the event. */ list_for_each_entry_rcu(intf, &ipmi_interfaces, link) { if (!intf->handlers) @@ -4289,18 +4322,7 @@ static void send_panic_events(char *str) intf->run_to_completion = 1; /* Send the event announcing the panic. */ intf->handlers->set_run_to_completion(intf->send_info, 1); - i_ipmi_request(NULL, - intf, - &addr, - 0, - &msg, - intf, - &smi_msg, - &recv_msg, - 0, - intf->channels[0].address, - intf->channels[0].lun, - 0, 1); /* Don't retry, and don't wait. */ + ipmi_panic_request_and_wait(intf, &addr, &msg); } #ifdef CONFIG_IPMI_PANIC_STRING @@ -4348,18 +4370,7 @@ static void send_panic_events(char *str) msg.data = NULL; msg.data_len = 0; intf->null_user_handler = device_id_fetcher; - i_ipmi_request(NULL, - intf, - &addr, - 0, - &msg, - intf, - &smi_msg, - &recv_msg, - 0, - intf->channels[0].address, - intf->channels[0].lun, - 0, 1); /* Don't retry, and don't wait. */ + ipmi_panic_request_and_wait(intf, &addr, &msg); if (intf->local_event_generator) { /* Request the event receiver from the local MC. */ @@ -4368,18 +4379,7 @@ static void send_panic_events(char *str) msg.data = NULL; msg.data_len = 0; intf->null_user_handler = event_receiver_fetcher; - i_ipmi_request(NULL, - intf, - &addr, - 0, - &msg, - intf, - &smi_msg, - &recv_msg, - 0, - intf->channels[0].address, - intf->channels[0].lun, - 0, 1); /* no retry, and no wait. */ + ipmi_panic_request_and_wait(intf, &addr, &msg); } intf->null_user_handler = NULL; @@ -4436,18 +4436,7 @@ static void send_panic_events(char *str) strncpy(data+5, p, 11); p += size; - i_ipmi_request(NULL, - intf, - &addr, - 0, - &msg, - intf, - &smi_msg, - &recv_msg, - 0, - intf->channels[0].address, - intf->channels[0].lun, - 0, 1); /* no retry, and no wait. */ + ipmi_panic_request_and_wait(intf, &addr, &msg); } } #endif /* CONFIG_IPMI_PANIC_STRING */ diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c index 34767a6d7f42..57a53ba7758c 100644 --- a/drivers/char/ipmi/ipmi_watchdog.c +++ b/drivers/char/ipmi/ipmi_watchdog.c @@ -520,6 +520,7 @@ static void panic_halt_ipmi_heartbeat(void) msg.cmd = IPMI_WDOG_RESET_TIMER; msg.data = NULL; msg.data_len = 0; + atomic_add(2, &panic_done_count); rv = ipmi_request_supply_msgs(watchdog_user, (struct ipmi_addr *) &addr, 0, @@ -528,8 +529,8 @@ static void panic_halt_ipmi_heartbeat(void) &panic_halt_heartbeat_smi_msg, &panic_halt_heartbeat_recv_msg, 1); - if (!rv) - atomic_add(2, &panic_done_count); + if (rv) + atomic_sub(2, &panic_done_count); } static struct ipmi_smi_msg panic_halt_smi_msg = { @@ -553,16 +554,18 @@ static void panic_halt_ipmi_set_timeout(void) /* Wait for the messages to be free. */ while (atomic_read(&panic_done_count) != 0) ipmi_poll_interface(watchdog_user); + atomic_add(2, &panic_done_count); rv = i_ipmi_set_timeout(&panic_halt_smi_msg, &panic_halt_recv_msg, &send_heartbeat_now); - if (!rv) { - atomic_add(2, &panic_done_count); - if (send_heartbeat_now) - panic_halt_ipmi_heartbeat(); - } else + if (rv) { + atomic_sub(2, &panic_done_count); printk(KERN_WARNING PFX "Unable to extend the watchdog timeout."); + } else { + if (send_heartbeat_now) + panic_halt_ipmi_heartbeat(); + } while (atomic_read(&panic_done_count) != 0) ipmi_poll_interface(watchdog_user); } -- 2.20.1