scsi: libfc: Add WARN_ON() when deleting rports

hreinecke · martinkpetersen · commit bbc0f8bd88ab · 2018-07-12T23:01:16.000-04:00
The discovery rport list handling is quite odd; the list traversal is
independent from the lifetime of the rport itself. This makes auditing
quite tricky, and the chance remains that we've missed something.  So this
patch adds a WARN_ON() statement when freeing an rport which is still part
of a list.

Signed-off-by: Hannes Reinecke &lt;hare@suse.com&gt;
Reviewed-by: Johannes Thumshirn &lt;jthumshirn@suse.de&gt;
Signed-off-by: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
diff --git a/drivers/scsi/libfc/fc_rport.c b/drivers/scsi/libfc/fc_rport.c
@@ -184,6 +184,7 @@ void fc_rport_destroy(struct kref *kref)
 	struct fc_rport_priv *rdata;
 
 	rdata = container_of(kref, struct fc_rport_priv, kref);
+	WARN_ON(!list_empty(&rdata->peers));
 	kfree_rcu(rdata, rcu);
 }
 EXPORT_SYMBOL(fc_rport_destroy);

Original file line number	Diff line number	Diff line change
`@@ -184,6 +184,7 @@ void fc_rport_destroy(struct kref *kref)`
`184`	`184`	`struct fc_rport_priv *rdata;`
`185`	`185`
`186`	`186`	`rdata = container_of(kref, struct fc_rport_priv, kref);`
	`187`	`+ WARN_ON(!list_empty(&rdata->peers));`
`187`	`188`	`kfree_rcu(rdata, rcu);`
`188`	`189`	`}`
`189`	`190`	`EXPORT_SYMBOL(fc_rport_destroy);`