Re: [RFC PATCH net 0/2] Make phylink and DSA wait for PHY driver that defers probe

[Andrew Lunn <andrew@lunn.ch>]

> > There is a very different approach, which might be simpler.
> > 
> > We know polling will always work. And it should be possible to
> > transition between polling and interrupt at any point, so long as the
> > phylock is held. So if you get -EPROBE_DEFFER during probe, mark some
> > state in phydev that there should be an irq, but it is not around yet.
> > When the phy is started, and phylib starts polling, look for the state
> > and try getting the IRQ again. If successful, swap to interrupts, if
> > not, keep polling. Maybe after 60 seconds of polling and trying, give
> > up trying to find the irq and stick with polling.
> 
> That doesn't sound like something that I'd backport to stable kernels.

> What motivates me to make these changes in the first place is the idea
> that current kernels should work with updated device trees.

By current, you mean old kernels, LTS etc. You want an LTS kernel to
work with a new DT blob? You want forward compatibility with a DT
blob. Do the stable rules say anything about that?

      Andrew