[SCSI] ipr: Fix a race on multiple configuration changes
In a multiple configuration change scenario a remove notification can be
followed by an immediate add notification for the same device, which
will cause the device to be removed but never added back. This patch
fixes the problem by ensuring that in such situations the device will be
added back.
Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index a8e24f0..1485767 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -1301,7 +1301,7 @@
ipr_clear_res_target(res);
list_move_tail(&res->queue, &ioa_cfg->free_res_q);
}
- } else if (!res->sdev) {
+ } else if (!res->sdev || res->del_from_ml) {
res->add_to_ml = 1;
if (ioa_cfg->allow_ml_add_del)
schedule_work(&ioa_cfg->work_q);
@@ -3104,7 +3104,10 @@
did_work = 1;
sdev = res->sdev;
if (!scsi_device_get(sdev)) {
- list_move_tail(&res->queue, &ioa_cfg->free_res_q);
+ if (!res->add_to_ml)
+ list_move_tail(&res->queue, &ioa_cfg->free_res_q);
+ else
+ res->del_from_ml = 0;
spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
scsi_remove_device(sdev);
scsi_device_put(sdev);