[ Upstream commit 4c7f3950a9fd53a62b156c0fe7c3a2c43b0ba19b ]
Since commit a3c53be55c95 ("net: dsa: mv88e6xxx: Support multiple MDIO
busses") mv88e6xxx_default_mdio_bus() has checked that the
return value of list_first_entry() is non-NULL.
This appears to be intended to guard against the list chip->mdios being
empty. However, it is not the correct check as the implementation of
list_first_entry is not designed to return NULL for empty lists.
Instead, use list_first_entry_or_null() which does return NULL if the
list is empty.
Flagged by Smatch.
Compile tested only.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240430-mv88e6xx-list_empty-v3-1-c35c69d88d2e@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>