OMAP baseline test results for v3.16-rc4
paul at pwsan.com
Thu Aug 7 23:14:07 PDT 2014
On Thu, 7 Aug 2014, Fabio Estevam wrote:
> On Thu, Aug 7, 2014 at 7:21 PM, Paul Walmsley <paul at pwsan.com> wrote:
> > It's commit a71e3c37960ce5f9c6a519bc1215e3ba9fa83e75:
> > Author: Ezequiel Garcia <ezequiel.garcia at 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 at gmail.com>
> > Tested-by: Florian Fainelli <f.fainelli at gmail.com>
> > Signed-off-by: Ezequiel Garcia <ezequiel.garcia at free-electrons.com>
> > Signed-off-by: David S. Miller <davem at 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
Makes sense to me.
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