3.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Stefan Haberland <[email protected]> [ Upstream commit 2202134e48a3b50320aeb9e3dd1186833e9d7e66 ] Check if the device pointer is valid. Just a sanity check since we already are in the int handler of the device. Signed-off-by: Stefan Haberland <[email protected]> Signed-off-by: Martin Schwidefsky <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/s390/block/dasd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -1672,8 +1672,11 @@ void dasd_int_handler(struct ccw_device /* check for for attention message */ if (scsw_dstat(&irb->scsw) & DEV_STAT_ATTENTION) { device = dasd_device_from_cdev_locked(cdev); - device->discipline->check_attention(device, irb->esw.esw1.lpum); - dasd_put_device(device); + if (!IS_ERR(device)) { + device->discipline->check_attention(device, + irb->esw.esw1.lpum); + dasd_put_device(device); + } } if (!cqr)
