[PATCH 5.4 14/84] net: mdiobus: get rid of a BUG_ON()

Greg Kroah-Hartman
2021-06-14T10:53:28Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 1dde47a66d4fb181830d6fa000e5ea86907b639e ]

We spotted a bug recently during a review where a driver was
unregistering a bus that wasn't registered, which would trigger this
BUG_ON(). Let's handle that situation more gracefully, and just print
a warning and return.

Reported-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/phy/mdio_bus.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 229e480179ff..5bf06eac04ba 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -453,7 +453,8 @@ void mdiobus_unregister(struct mii_bus *bus)
struct mdio_device *mdiodev;
int i;

- BUG_ON(bus->state != MDIOBUS_REGISTERED);
+ if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED))
+ return;
bus->state = MDIOBUS_UNREGISTERED;

for (i = 0; i < PHY_MAX_ADDR; i++) {
--
2.30.2