| Message ID | 20160609004456.5441-5-vivien.didelot@savoirfairelinux.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
On Wed, Jun 08, 2016 at 08:44:52PM -0400, Vivien Didelot wrote: > The MDIO device probe and remove functions are respectively incrementing > and decrementing the bus refcount themselves. Since these bus level > actions are out of the device scope, remove them. I agree with the patch. But have you checked the mdio layer is doing the right thing? If not, we should fix that first. Andrew
Hi, Andrew Lunn <andrew@lunn.ch> writes: > On Wed, Jun 08, 2016 at 08:44:52PM -0400, Vivien Didelot wrote: >> The MDIO device probe and remove functions are respectively incrementing >> and decrementing the bus refcount themselves. Since these bus level >> actions are out of the device scope, remove them. > > I agree with the patch. But have you checked the mdio layer is doing > the right thing? If not, we should fix that first. So I added some printing after incrementing/decrementing the refcount in get_device/put_device to track &ps->bus->dev, which name is "0.1". Regardless having this patch or not, the refcount of the 0.1 mii_bus device is 5 before loading the mv88e6xxx module on vf610-zii-dev-rev-b. Below is a portion of dmesg: [ 8.921647] get_device: 400d1000.etherne refcount: 4 [ 8.926225] get_device: 0.1 refcount: 2 [ 8.929561] get_device: mdio-mux refcount: 5 [ 8.934076] get_device: 0.1 refcount: 3 [ 8.937446] get_device: 0.1 refcount: 4 [ 8.940792] put_device: 0.1 refcount: 3 [ 8.944181] libphy: mdio_mux: probed [ 8.947885] mdio_bus 0.1:00: mdio_device_register [ 8.952649] get_device: 0.1:00 refcount: 2 [ 8.956283] get_device: 0.1 refcount: 4 [ 8.959838] get_device: 0.1:00 refcount: 3 [ 8.963991] get_device: 0.1:00 refcount: 4 [ 8.967598] put_device: 0.1:00 refcount: 3 [ 8.971298] get_device: 0.2 refcount: 2 [ 8.974687] get_device: mdio-mux refcount: 7 So it seems like of_ is managing the bus refcount on events such as a new child node (0.1:00). Thanks, Vivien
On Fri, Jun 10, 2016 at 03:59:22PM -0400, Vivien Didelot wrote: > Hi, > > Andrew Lunn <andrew@lunn.ch> writes: > > > On Wed, Jun 08, 2016 at 08:44:52PM -0400, Vivien Didelot wrote: > >> The MDIO device probe and remove functions are respectively incrementing > >> and decrementing the bus refcount themselves. Since these bus level > >> actions are out of the device scope, remove them. > > > > I agree with the patch. But have you checked the mdio layer is doing > > the right thing? If not, we should fix that first. > > So I added some printing after incrementing/decrementing the refcount in > get_device/put_device to track &ps->bus->dev, which name is "0.1". > > Regardless having this patch or not, the refcount of the 0.1 mii_bus > device is 5 before loading the mv88e6xxx module on vf610-zii-dev-rev-b. > > Below is a portion of dmesg: > > [ 8.921647] get_device: 400d1000.etherne refcount: 4 > [ 8.926225] get_device: 0.1 refcount: 2 > [ 8.929561] get_device: mdio-mux refcount: 5 > [ 8.934076] get_device: 0.1 refcount: 3 > [ 8.937446] get_device: 0.1 refcount: 4 > [ 8.940792] put_device: 0.1 refcount: 3 > [ 8.944181] libphy: mdio_mux: probed > [ 8.947885] mdio_bus 0.1:00: mdio_device_register > [ 8.952649] get_device: 0.1:00 refcount: 2 > [ 8.956283] get_device: 0.1 refcount: 4 > [ 8.959838] get_device: 0.1:00 refcount: 3 > [ 8.963991] get_device: 0.1:00 refcount: 4 > [ 8.967598] put_device: 0.1:00 refcount: 3 > [ 8.971298] get_device: 0.2 refcount: 2 > [ 8.974687] get_device: mdio-mux refcount: 7 > > So it seems like of_ is managing the bus refcount on events such as a > new child node (0.1:00). Great, thanks for looking at this. Acked-by: Andrew Lunn <andrew@lunn.ch> Andrew
diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c index cfa30ae..02b0af7 100644 --- a/drivers/net/dsa/mv88e6xxx.c +++ b/drivers/net/dsa/mv88e6xxx.c @@ -3710,8 +3710,6 @@ int mv88e6xxx_probe(struct mdio_device *mdiodev) ps->sw_addr = mdiodev->addr; mutex_init(&ps->smi_mutex); - get_device(&ps->bus->dev); - ds->drv = &mv88e6xxx_switch_driver; id = mv88e6xxx_reg_read(ps, REG_PORT(0), PORT_SWITCH_ID); @@ -3765,7 +3763,6 @@ static void mv88e6xxx_remove(struct mdio_device *mdiodev) struct mv88e6xxx_priv_state *ps = ds_to_priv(ds); dsa_unregister_switch(ds); - put_device(&ps->bus->dev); mv88e6xxx_mdio_unregister(ps); }
The MDIO device probe and remove functions are respectively incrementing and decrementing the bus refcount themselves. Since these bus level actions are out of the device scope, remove them. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> --- drivers/net/dsa/mv88e6xxx.c | 3 --- 1 file changed, 3 deletions(-)