8 Aug
2014
8 Aug
'14
6:14 a.m.
On Thu, 7 Aug 2014, Fabio Estevam wrote:
On Thu, Aug 7, 2014 at 7:21 PM, Paul Walmsley paul@pwsan.com wrote:
It's commit a71e3c37960ce5f9c6a519bc1215e3ba9fa83e75:
Author: Ezequiel Garcia ezequiel.garcia@free-electrons.com Date: Wed Jul 23 16:47:31 2014 -0300
net: phy: Set the driver when registering an MDIO bus device mdiobus_register() registers a device which is already bound to a driver. Hence, the driver pointer should be set properly in order to track down the driver associated to the MDIO bus. This will be used to allow ethernet driver to pin down a MDIO bus driver, preventing it from being unloaded while the PHY device is running. Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by: David S. Miller <davem@davemloft.net>What's bad is that this went in late during v3.16-rc fixes. So now v3.16 itself is broken, and there's no way to fix it.
I have sent a patch reverting this commit and it is in mainline now.
That's great; thanks for letting us know.
The problem with the original commit is explained by Russell King: "It has the effect (as can be seen from the oops) of attaching the MDIO bus device (itself is a bus-less device) to the platform driver, which means that if the platform driver supports power management, it will be called to power manage the MDIO bus device. Moreover, drivers do not expect to be called for power management operations for devices which they haven't probed, and certainly not for devices which aren't part of the same bus that the driver is registered against."
Makes sense to me.
- Paul