scsi: qla2xxx: Unable to act on RSCN for port online

commit c3d98b12eef8db436e32f1a8c5478be57dc15621 upstream.

The device does not come online when the target port is online. There were
multiple RSCNs indicating multiple devices were affected. Driver is in the
process of finishing a fabric scan. A new RSCN (device up) arrived at the
tail end of the last fabric scan. Driver mistakenly thinks the new RSCN is
being taken care of by the previous fabric scan, where this notification is
cleared and not acted on. The laser needs to be blinked again to get the
device to show up.

To prevent driver from accidentally clearing the RSCN notification, each
RSCN is given a generation value.  A fabric scan will scan for that
generation(s).  Any new RSCN arrive after the scan start will have a new
generation value. This will trigger another scan to get latest data. The
RSCN notification flag will be cleared when the scan is associate to that
generation.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202406210538.w875N70K-lkp@intel.com/


Fixes: bb2ca6b3 ("scsi: qla2xxx: Relogin during fabric disturbance")
Cc: stable@vger.kernel.org
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://lore.kernel.org/r/20240710171057.35066-2-njavali@marvell.com


Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>