Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 16 Sep 2021 11:08:35 +0200
From:   Johan Hovold <johan@kernel.org>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>, Li Yang <leoyang.li@nxp.com>,
        Scott Wood <oss@buserror.net>,
        "open list:SERIAL DRIVERS" <linux-serial@vger.kernel.org>,
        linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] serial: 8250: SERIAL_8250_FSL should not default to y
 when compile-testing
Message-ID: <YUMJk6VKI40Caq5x@hovoldconsulting.com>
References: <c5f8aa5c081755f3c960b86fc61c2baaa33edcd9.1631710216.git.geert+renesas@glider.be>
 <YUMESxr907YHM3ZT@hovoldconsulting.com>
 <CAMuHMdX7_AOuGEjvTHpQ-4KHMH+m800KTu7wads6UTfMZiu9BQ@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAMuHMdX7_AOuGEjvTHpQ-4KHMH+m800KTu7wads6UTfMZiu9BQ@mail.gmail.com>
Precedence: bulk

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@kernel.org> 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