ipmi/watchdog: fix wdog hang on panic waiting for ipmi response
authorRobert Lippert <roblip@gmail.com>
Thu, 20 Apr 2017 23:49:47 +0000 (16:49 -0700)
committerCorey Minyard <cminyard@mvista.com>
Fri, 28 Apr 2017 19:53:17 +0000 (14:53 -0500)
Commit c49c097610fe ("ipmi: Don't call receive handler in the
panic context") means that the panic_recv_free is not called during a
panic and the atomic count does not drop to 0.

Fix this by only expecting one decrement of the atomic variable
which comes from panic_smi_free.

Signed-off-by: Robert Lippert <rlippert@google.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
drivers/char/ipmi/ipmi_watchdog.c

index 5ca24d9..d165af8 100644 (file)
@@ -516,7 +516,7 @@ 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);
+       atomic_add(1, &panic_done_count);
        rv = ipmi_request_supply_msgs(watchdog_user,
                                      (struct ipmi_addr *) &addr,
                                      0,
@@ -526,7 +526,7 @@ static void panic_halt_ipmi_heartbeat(void)
                                      &panic_halt_heartbeat_recv_msg,
                                      1);
        if (rv)
-               atomic_sub(2, &panic_done_count);
+               atomic_sub(1, &panic_done_count);
 }
 
 static struct ipmi_smi_msg panic_halt_smi_msg = {
@@ -550,12 +550,12 @@ 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);
+       atomic_add(1, &panic_done_count);
        rv = i_ipmi_set_timeout(&panic_halt_smi_msg,
                                &panic_halt_recv_msg,
                                &send_heartbeat_now);
        if (rv) {
-               atomic_sub(2, &panic_done_count);
+               atomic_sub(1, &panic_done_count);
                printk(KERN_WARNING PFX
                       "Unable to extend the watchdog timeout.");
        } else {