[PATCH 4.19 112/149] Revert "scsi: libfc: Add WARN_ON() when deleting rports"

From: Greg Kroah-Hartman
Date: Tue Mar 12 2019 - 13:48:36 EST

4.19-stable review patch. If anyone has any objections, please let me know.


[ Upstream commit d8f6382a7d026989029e2e50c515df954488459b ]

This reverts commit bbc0f8bd88abefb0f27998f40a073634a3a2db89.

It added a warning whose intent was to check whether the rport was still
linked into the peer list. It doesn't work as intended and gives false
positive warnings for two reasons:

1) If the rport is never linked into the peer list it will not be
considered empty since the list_head is never initialized.

2) If the rport is deleted from the peer list using list_del_rcu(), then
the list_head is in an undefined state and it is not considered empty.

Signed-off-by: Ross Lagerwall <ross.lagerwall@xxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/scsi/libfc/fc_rport.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/scsi/libfc/fc_rport.c b/drivers/scsi/libfc/fc_rport.c
index 372387a450df..1797e47fab38 100644
--- a/drivers/scsi/libfc/fc_rport.c
+++ b/drivers/scsi/libfc/fc_rport.c
@@ -184,7 +184,6 @@ 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);