From: Roman Bolshakov r.bolshakov@yadro.com
commit 632f24f09d5b7c8a2f94932c3391ca957ae76cc4 upstream.
The driver performs SCR (state change registration) in all modes including pure target mode.
For each RSCN, scan_needed flag is set in qla2x00_handle_rscn() for the port mentioned in the RSCN and fabric rescan is scheduled. During the rescan, GNN_FT handler, qla24xx_async_gnnft_done() deletes session of the port that caused the RSCN.
In target mode, the session deletion has an impact on ATIO handler, qlt_24xx_atio_pkt(). Target responds with SAM STATUS BUSY to I/O incoming from the deleted session. qlt_handle_cmd_for_atio() and qlt_handle_task_mgmt() return -EFAULT if they are not able to find session of the command/TMF, and that results in invocation of qlt_send_busy():
qlt_24xx_atio_pkt_all_vps: qla_target(0): type 6 ox_id 0014 qla_target(0): Unable to send command to target, sending BUSY status
Such response causes command timeout on the initiator. Error handler thread on the initiator will be spawned to abort the commands:
scsi 23:0:0:0: tag#0 abort scheduled scsi 23:0:0:0: tag#0 aborting command qla2xxx [0000:af:00.0]-188c:23: Entered qla24xx_abort_command. qla2xxx [0000:af:00.0]-801c:23: Abort command issued nexus=23:0:0 -- 0 2003.
Command abort is rejected by target and fails (2003), error handler then tries to perform DEVICE RESET and TARGET RESET but they're also doomed to fail because TMFs are ignored for the deleted sessions.
Then initiator makes BUS RESET that resets the link via qla2x00_full_login_lip(). BUS RESET succeeds and brings initiator port up, SAN switch detects that and sends RSCN to the target port and it fails again the same way as described above. It never goes out of the loop.
The change breaks the RSCN loop by keeping initiator sessions mentioned in RSCN payload in all modes, including dual and pure target mode.
Link: https://lore.kernel.org/r/20200605144435.27023-1-r.bolshakov@yadro.com Fixes: 2037ce49d30a ("scsi: qla2xxx: Fix stale session") Cc: Quinn Tran qutran@marvell.com Cc: Arun Easi aeasi@marvell.com Cc: Nilesh Javali njavali@marvell.com Cc: Bart Van Assche bvanassche@acm.org Cc: Daniel Wagner dwagner@suse.de Cc: Himanshu Madhani himanshu.madhani@oracle.com Cc: Martin Wilck mwilck@suse.com Cc: stable@vger.kernel.org # v5.4+ Reviewed-by: Daniel Wagner dwagner@suse.de Reviewed-by: Shyam Sundar ssundar@marvell.com Reviewed-by: Himanshu Madhani himanshu.madhani@oracle.com Signed-off-by: Roman Bolshakov r.bolshakov@yadro.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/qla2xxx/qla_gs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/qla2xxx/qla_gs.c b/drivers/scsi/qla2xxx/qla_gs.c index 84bb4a0480166..a44de4c5dcf6c 100644 --- a/drivers/scsi/qla2xxx/qla_gs.c +++ b/drivers/scsi/qla2xxx/qla_gs.c @@ -3638,7 +3638,9 @@ void qla24xx_async_gnnft_done(scsi_qla_host_t *vha, srb_t *sp) qla2x00_clear_loop_id(fcport); fcport->flags |= FCF_FABRIC_DEVICE; } else if (fcport->d_id.b24 != rp->id.b24 || - fcport->scan_needed) { + (fcport->scan_needed && + fcport->port_type != FCT_INITIATOR && + fcport->port_type != FCT_NVME_INITIATOR)) { qlt_schedule_sess_for_deletion(fcport); } fcport->d_id.b24 = rp->id.b24;