[PATCH 3/6] zfcp: fix sysfs roll-back on error in zfcp_adapter_enqueue()

Benjamin Block
2021-04-14T17:08:21Z

From: Julian Wiedmann <jwi@linux.ibm.com>

When zfcp_adapter_enqueue() fails to create the zfcp_sysfs_adapter_attrs
group, it calls zfcp_adapter_unregister() to tear down the adapter state
again. This then unconditionally attempts to remove the
zfcp_sysfs_adapter_attrs group, resulting in a "group not found" WARN
from sysfs code.

Avoid this by copying most of zfcp_adapter_unregister() into the error
path, allowing for more fine-granular roll-back. Then skip the sysfs
tear-down steps if we haven't progressed this far in the initialization.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
---
drivers/s390/scsi/zfcp_aux.c | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index 768873dd55b8..abad77694e72 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -418,7 +418,7 @@ struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
goto failed;

if (zfcp_diag_sysfs_setup(adapter))
- goto failed;
+ goto err_diag_sysfs;

/* report size limit per scatter-gather segment */
adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
@@ -427,8 +427,24 @@ struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)

return adapter;

+err_diag_sysfs:
+ sysfs_remove_group(&ccw_device->dev.kobj, &zfcp_sysfs_adapter_attrs);
failed:
- zfcp_adapter_unregister(adapter);
+ /* TODO: make this more fine-granular */
+ cancel_delayed_work_sync(&adapter->scan_work);
+ cancel_work_sync(&adapter->stat_work);
+ cancel_work_sync(&adapter->ns_up_work);
+ cancel_work_sync(&adapter->version_change_lost_work);
+ zfcp_destroy_adapter_work_queue(adapter);
+
+ zfcp_fc_wka_ports_force_offline(adapter->gs);
+ zfcp_scsi_adapter_unregister(adapter);
+
+ zfcp_erp_thread_kill(adapter);
+ zfcp_dbf_adapter_unregister(adapter);
+ zfcp_qdio_destroy(adapter->qdio);
+
+ zfcp_ccw_adapter_put(adapter); /* final put to release */
return ERR_PTR(-ENOMEM);
}

--
2.30.2