[PATCH 4/6] ipmi: Fix message handling during panics
From: Corey Minyard
Date: Fri Feb 03 2012 - 11:48:45 EST
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 <cminyard@xxxxxxxxxx>
---
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 289ab50..5c1820c 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 34767a6..57a53ba 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);
}
--
1.7.4.1
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