[ Upstream commit ef4d6a85 ]

Check if the syndrome provided by the caller is zero, and act
accordingly.
Signed-off-by: Ferdinand Blomqvist <ferdinand.blomqvist@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190620141039.9874-6-ferdinand.blomqvist@gmail.comSigned-off-by: Sasha Levin <sashal@kernel.org>