4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@xxxxxxxxxxxxx> 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() Signed-off-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@xxxxxxxxxxxxx> Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/aacraid/commsup.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/drivers/scsi/aacraid/commsup.c +++ b/drivers/scsi/aacraid/commsup.c @@ -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()) -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html