Re: [PATCH] serial: 8250: SERIAL_8250_FSL should not default to y when compile-testing

From: Johan Hovold
Date: Thu Sep 16 2021 - 05:08:41 EST


On Thu, Sep 16, 2021 at 10:55:49AM +0200, Geert Uytterhoeven wrote:
> Hi Johan,
>
> On Thu, Sep 16, 2021 at 10:46 AM Johan Hovold <johan@xxxxxxxxxx> wrote:
> > On Wed, Sep 15, 2021 at 02:56:52PM +0200, Geert Uytterhoeven wrote:
> > > Commit b1442c55ce8977aa ("serial: 8250: extend compile-test coverage")
> > > added compile-test support to the Freescale 16550 driver. However, as
> > > SERIAL_8250_FSL is an invisible symbol, merely enabling COMPILE_TEST now
> > > enables this driver.
> > >
> > > Fix this by making SERIAL_8250_FSL visible. Tighten the dependencies to
> > > prevent asking the user about this driver when configuring a kernel
> > > without appropriate Freescale SoC or ACPI support.
> >
> > This tightening is arguable a separate change which risk introducing
> > regressions if you get it wrong and should go in a separate patch at
> > least.
>
> Getting it wrong would indeed be a regression, but not tightening
> that at the same time would mean I have to send a separate patch with
> a Fixes tag referring to this fix, following this template:
>
> foo should depend on bar
>
> The foo hardware is only present on bar SoCs. Hence add a
> dependency on bar, to prevent asking the user about this driver
> when configuring a kernel without bar support.

I know this is a pet peeve of yours, but asking users about one more
symbol when configuring their kernels is hardly something that requires
a Fixes tag.

Either way it's a pretty weak argument for not separating the change.

Johan