On 29-10-17, 13:01, Johan Hovold wrote: > Remove erroneous spi_master_put() after controller deregistration which > would access the already freed spi controller. > > Note that spi_unregister_master() drops our only controller reference. > > Fixes: ba3e67001b42 ("greybus: SPI: convert to a gpbridge driver") > Cc: stable <sta...@vger.kernel.org> # 4.9 > Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> > Signed-off-by: Johan Hovold <jo...@kernel.org> > --- > drivers/staging/greybus/spilib.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/staging/greybus/spilib.c > b/drivers/staging/greybus/spilib.c > index e97b19148497..1e7321a1404c 100644 > --- a/drivers/staging/greybus/spilib.c > +++ b/drivers/staging/greybus/spilib.c > @@ -544,11 +544,14 @@ int gb_spilib_master_init(struct gb_connection > *connection, struct device *dev, > > return 0; > > -exit_spi_unregister: > - spi_unregister_master(master); > exit_spi_put: > spi_master_put(master); > > + return ret; > + > +exit_spi_unregister: > + spi_unregister_master(master); > + > return ret; > } > EXPORT_SYMBOL_GPL(gb_spilib_master_init); > @@ -558,7 +561,6 @@ void gb_spilib_master_exit(struct gb_connection > *connection) > struct spi_master *master = gb_connection_get_data(connection); > > spi_unregister_master(master); > - spi_master_put(master); > } > EXPORT_SYMBOL_GPL(gb_spilib_master_exit);
Acked-by: Viresh Kumar <viresh.ku...@linaro.org> While looking at this I think I found another problem (I will send it as a separate patch later on) and this fixes it: diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 6e65524cbfd9..af7ca751b4f7 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2261,11 +2261,11 @@ void spi_unregister_controller(struct spi_controller *ctlr) mutex_unlock(&board_lock); dummy = device_for_each_child(&ctlr->dev, NULL, __unregister); - device_unregister(&ctlr->dev); /* free bus id */ mutex_lock(&board_lock); idr_remove(&spi_master_idr, ctlr->bus_num); mutex_unlock(&board_lock); + device_unregister(&ctlr->dev); } EXPORT_SYMBOL_GPL(spi_unregister_controller); -- viresh