Re: [PATCH 3/4] Drivers: hv: vmbus: Add hooks for per-CPU IRQ
From: Greg KH
Date: Tue Nov 27 2018 - 01:21:03 EST
On Mon, Nov 26, 2018 at 08:56:50PM +0000, Michael Kelley wrote:
> From: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> Monday, November 26, 2018 11:57 AM
>
> > > > You created "null" hooks that do nothing, for no one in this patch
> > > > series, why?
> > > >
> > >
> > > hv_enable_vmbus_irq() and hv_disable_vmbus_irq() have non-null
> > > implementations in the ARM64 code in patch 2 of this series. The
> > > implementations are in the new file arch/arm64/hyperv/mshyperv.c.
> > > Or am I misunderstanding your point?
> >
> > So you use a hook in an earlier patch and then add it in a later one?
> >
> > Shouldn't you do it the other way around? As it is, the earlier patch
> > should not work properly, right?
>
> The earlier patch implements the hook on the ARM64 side but it is
> unused -- it's not called. The later patch then calls it. Wouldn't the
> other way around be backwards?
Ah, it wasn't obvious that the previous patch added it at all, why not
just make that addition part of this patch?
> The general approach is for patches 1 and 2 of the series to provide
> all the new code under arch/arm64 to enable Hyper-V. But the code
> won't get called (or even built) with just these two patches because
> CONFIG_HYPERV can't be selected. Patch 3 is separate because it
> applies to architecture independent code and arch/x86 code -- I thought
> there might be value in keeping the ARM64 and x86 patches distinct.
> Patch 4 applies to architecture independent code, and enables the
> ARM64 code in patches 1 and 2 to be compiled and run when
> CONFIG_HYPERV is selected.
>
> If combining some of the patches in the series is a better approach, I'm
> good with that.
Ok, that makes more sense, if it is easier to get the ARM people to
review this, that's fine. Doesn't seem like anyone did that yet :(
sorry for the noise,
greg k-h