On 2022/4/14 23:30, Mike Christie wrote: > On 4/13/22 8:49 PM, Wenchao Hao wrote: >> __iscsi_unbind_session() set session state to ISCSI_SESSION_UNBOUND, which >> would overwrite the ISCSI_SESSION_FREE state. >> >> Signed-off-by: Wenchao Hao <haowenchao@xxxxxxxxxx> >> --- >> drivers/scsi/scsi_transport_iscsi.c | 26 ++++++++++++++++---------- >> 1 file changed, 16 insertions(+), 10 deletions(-) >> >> diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c >> index 97a9fee02efa..d8dd9279cea8 100644 >> --- a/drivers/scsi/scsi_transport_iscsi.c >> +++ b/drivers/scsi/scsi_transport_iscsi.c >> @@ -2173,6 +2173,22 @@ void iscsi_remove_session(struct iscsi_cls_session *session) >> if (!cancel_work_sync(&session->block_work)) >> cancel_delayed_work_sync(&session->recovery_work); >> cancel_work_sync(&session->unblock_work); >> + >> + scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE); >> + /* >> + * qla4xxx can perform it's own scans when it runs in kernel only >> + * mode. Make sure to flush those scans. >> + */ >> + flush_work(&session->scan_work); >> + >> + /* >> + * flush running unbind operations >> + * if unbind work did not queued, call __iscsi_unbind_session >> + * directly to perform target remove > > We probably don't need the flush_work test because we are going to > normally call __iscsi_unbind_session. > I think we still need calling flush_work here. The introduce of flush_work is to make sure sysfs objects are removed in an correct order. There is a very low probability that __iscsi_unbind_session() triggered by queue_work() has not been finished, and iscsi_remove_session() is called. So we need flush_work() to make sure __iscsi_unbind_session() has done if it has been activated by queue_work(). > If the unbind work had already run, which is the normal case, then > flush_work returns false and we end up calling __iscsi_unbind_session > like before. That function then checks if the target is really unbound. > So the extra check doesn't normally buy us anything with your patches > because in patch 1 you fixed it so __iscsi_unbind_session doesn't send > the extra event. > > >> + */ >> + if (!flush_work(&session->unbind_work)) >> + __iscsi_unbind_session(&session->unbind_work); >> + >> /* >> * If we are blocked let commands flow again. The lld or iscsi >> * layer should set up the queuecommand to fail commands. >> @@ -2183,16 +2199,6 @@ void iscsi_remove_session(struct iscsi_cls_session *session) >> session->state = ISCSI_SESSION_FREE; >> spin_unlock_irqrestore(&session->lock, flags); >> >> - scsi_target_unblock(&session->dev, SDEV_TRANSPORT_OFFLINE); >> - /* >> - * qla4xxx can perform it's own scans when it runs in kernel only >> - * mode. Make sure to flush those scans. >> - */ >> - flush_work(&session->scan_work); >> - /* flush running unbind operations */ >> - flush_work(&session->unbind_work); >> - __iscsi_unbind_session(&session->unbind_work); >> - >> /* hw iscsi may not have removed all connections from session */ >> err = device_for_each_child(&session->dev, NULL, >> iscsi_iter_destroy_conn_fn); > > .
