hpsa-do-not-ack-controller-events-on-controllers-that-do-not-support-it

hpsa: do not ack controller events on controllers that do not support it

From: Stephen M. Cameron <scameron@beardog.cce.hp.com>

Doing so can cause such controllers to lock up.

Signed-off-by: Joe Handzik <joseph.t.handzik@hp.com>
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Reviewed-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
---
 drivers/scsi/hpsa.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index a91907d..4a388e2 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -7185,6 +7185,9 @@ static void hpsa_ack_ctlr_events(struct ctlr_info *h)
 	int i;
 	char *event_type;
 
+	if (!(h->fw_support & MISC_FW_EVENT_NOTIFY))
+		return;
+
 	/* Ask the controller to clear the events we're handling. */
 	if ((h->transMethod & (CFGTBL_Trans_io_accel1
 			| CFGTBL_Trans_io_accel2)) &&