Patch "aacraid: Fix for aac_command_thread hang" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

aacraid: Fix for aac_command_thread hang

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
aacraid-fix-for-aac_command_thread-hang.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Raghava Aditya Renukunta <[email protected]>
Date: Mon, 25 Apr 2016 23:31:57 -0700
Subject: aacraid: Fix for aac_command_thread hang

From: Raghava Aditya Renukunta <[email protected]>

commit fc4bf75ea300a5e62a2419f89dd0e22189dd7ab7 upstream.

Typically under error conditions, it is possible for aac_command_thread() to miss the wakeup from kthread_stop() and go back to sleep, causing it to hang aac_shutdown.

In the observed scenario, the adapter is not functioning correctly and so aac_fib_send() never completes (or time-outs depending on how it was called). Shortly after aac_command_thread() starts it performs aac_fib_send(SendHostTime) which hangs. When aac_probe_one /aac_get_adapter_info send time outs, kthread_stop is called which breaks the command thread out of it's hang.

The code will still go back to sleep in schedule_timeout() without checking kthread_should_stop() so it causes aac_probe_one to hang until the schedule_timeout() which is 30 minutes.

Fixed by: Adding another kthread_should_stop() before schedule_timeout()

---
 drivers/scsi/aacraid/commsup.c |    4 ++++
 1 file changed, 4 insertions(+)

@@ -1970,6 +1970,10 @@ int aac_command_thread(void *data)
 		if (difference <= 0)
 			difference = 1;
 		set_current_state(TASK_INTERRUPTIBLE);
+
+		if (kthread_should_stop())
+			break;
+
 		schedule_timeout(difference);
 
 		if (kthread_should_stop())

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/aacraid-fix-for-kdump-driver-hang.patch queue-4.4/aacraid-fix-for-aac_command_thread-hang.patch queue-4.4/aacraid-relinquish-cpu-during-timeout-wait.patch