ipmi_watchdog: restore settings when BMC reset

If the BMC gets reset, it will return 0x80 response errors.

In less than a week
# grep "Error 80 on cmd 22" /var/log/kernel |wc -l
378681

In this case, it is probably a good idea to restore the IPMI settings.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Tested-by: Arkadiusz Miśkiewicz <a.miskiewicz@gmail.com>
Reported-by: Arkadiusz Miśkiewicz <a.miskiewicz@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
index c2917ffad2c2a311beeeaed7f8171196601d78ff..34767a6d7f42a354edca655d901c298e3883609a 100644 (file)
--- a/drivers/char/ipmi/ipmi_watchdog.c
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -139,6 +139,8 @@
 #define IPMI_WDOG_SET_TIMER            0x24
 #define IPMI_WDOG_GET_TIMER            0x25
 
+#define IPMI_WDOG_TIMER_NOT_INIT_RESP  0x80
+
 /* These are here until the real ones get into the watchdog.h interface. */
 #ifndef WDIOC_GETTIMEOUT
 #define        WDIOC_GETTIMEOUT        _IOW(WATCHDOG_IOCTL_BASE, 20, int)
@@ -596,6 +598,7 @@ static int ipmi_heartbeat(void)
        struct kernel_ipmi_msg            msg;
        int                               rv;
        struct ipmi_system_interface_addr addr;
+       int                               timeout_retries = 0;
 
        if (ipmi_ignore_heartbeat)
                return 0;
@@ -616,6 +619,7 @@ static int ipmi_heartbeat(void)
 
        mutex_lock(&heartbeat_lock);
 
+restart:
        atomic_set(&heartbeat_tofree, 2);
 
        /*
@@ -653,7 +657,33 @@ static int ipmi_heartbeat(void)
        /* Wait for the heartbeat to be sent. */
        wait_for_completion(&heartbeat_wait);
 
-       if (heartbeat_recv_msg.msg.data[0] != 0) {
+       if (heartbeat_recv_msg.msg.data[0] == IPMI_WDOG_TIMER_NOT_INIT_RESP)  {
+               timeout_retries++;
+               if (timeout_retries > 3) {
+                       printk(KERN_ERR PFX ": Unable to restore the IPMI"
+                              " watchdog's settings, giving up.\n");
+                       rv = -EIO;
+                       goto out_unlock;
+               }
+
+               /*
+                * The timer was not initialized, that means the BMC was
+                * probably reset and lost the watchdog information.  Attempt
+                * to restore the timer's info.  Note that we still hold
+                * the heartbeat lock, to keep a heartbeat from happening
+                * in this process, so must say no heartbeat to avoid a
+                * deadlock on this mutex.
+                */
+               rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB);
+               if (rv) {
+                       printk(KERN_ERR PFX ": Unable to send the command to"
+                              " set the watchdog's settings, giving up.\n");
+                       goto out_unlock;
+               }
+
+               /* We might need a new heartbeat, so do it now */
+               goto restart;
+       } else if (heartbeat_recv_msg.msg.data[0] != 0) {
                /*
                 * Got an error in the heartbeat response.  It was already
                 * reported in ipmi_wdog_msg_handler, but we should return
@@ -662,6 +692,7 @@ static int ipmi_heartbeat(void)
                rv = -EINVAL;
        }
 
+out_unlock:
        mutex_unlock(&heartbeat_lock);
 
        return rv;
@@ -922,11 +953,15 @@ static struct miscdevice ipmi_wdog_miscdev = {
 static void ipmi_wdog_msg_handler(struct ipmi_recv_msg *msg,
                                  void                 *handler_data)
 {
-       if (msg->msg.data[0] != 0) {
+       if (msg->msg.cmd == IPMI_WDOG_RESET_TIMER &&
+                       msg->msg.data[0] == IPMI_WDOG_TIMER_NOT_INIT_RESP)
+               printk(KERN_INFO PFX "response: The IPMI controller appears"
+                      " to have been reset, will attempt to reinitialize"
+                      " the watchdog timer\n");
+       else if (msg->msg.data[0] != 0)
                printk(KERN_ERR PFX "response: Error %x on cmd %x\n",
                       msg->msg.data[0],
                       msg->msg.cmd);
-       }
 
        ipmi_free_recv_msg(msg);
 }