4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sudip Mukherjee <sudipm.mukherjee@xxxxxxxxx> commit 03270c6ac6207fc55bbf9d20d195029dca210c79 upstream. Usually every parallel port will have a single pardev registered with it. But ppdev driver is an exception. This userspace parallel port driver allows to create multiple parrallel port devices for a single parallel port. And as a result we were having a nice warning like: "sysctl table check failed: /dev/parport/parport0/devices/ppdev0/timeslice Sysctl already exists" Use the same logic as used in parport_register_device() and register the proc files only once for each parallel port. Fixes: 6fa45a226897 ("parport: add device-model to parport subsystem") Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1414656 Bugzilla: https://bugs.archlinux.org/task/52322 Tested-by: James Feeney <james@xxxxxxxxxxx> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/parport/share.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/parport/share.c +++ b/drivers/parport/share.c @@ -936,8 +936,10 @@ parport_register_dev_model(struct parpor * pardevice fields. -arca */ port->ops->init_state(par_dev, par_dev->state); - port->proc_device = par_dev; - parport_device_proc_register(par_dev); + if (!test_and_set_bit(PARPORT_DEVPROC_REGISTERED, &port->devflags)) { + port->proc_device = par_dev; + parport_device_proc_register(par_dev); + } return par_dev;