Re: [PATCH] Ask user input only when CONFIG_X86 or CONFIG_COMPILE_TEST is set to y

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Narendra K <Narendra.K@dell.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	linux-efi <linux-efi@vger.kernel.org>,
	Mario Limonciello <Mario.Limonciello@dell.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	James Morse <james.morse@arm.com>, Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH] Ask user input only when CONFIG_X86 or CONFIG_COMPILE_TEST is set to y
Date: Fri, 11 Oct 2019 12:01:25 +0200	[thread overview]
Message-ID: <CAMuHMdUMkyyCZACyJ7dvd4SaicpN77g5pFd0aGEzQW_q7m3Q0g@mail.gmail.com> (raw)
In-Reply-To: <20191011094322.GA3065@localhost.localdomain>

Hi Narendra,

On Fri, Oct 11, 2019 at 11:43 AM <Narendra.K@dell.com> wrote:
> On Thu, Oct 10, 2019 at 08:50:45PM +0200, Geert Uytterhoeven wrote:
> [...]
> > > > >  drivers/firmware/efi/Kconfig | 5 ++++-
> > > > >  1 file changed, 4 insertions(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
> > > > > index 178ee8106828..6e4c46e8a954 100644
> > > > > --- a/drivers/firmware/efi/Kconfig
> > > > > +++ b/drivers/firmware/efi/Kconfig
> > > > > @@ -181,7 +181,10 @@ config RESET_ATTACK_MITIGATION
> > > > >           reboots.
> > > > >
> > > > >  config EFI_RCI2_TABLE
> > > > > -       bool "EFI Runtime Configuration Interface Table Version 2 Support"
> > > > > +       bool
> > > > > +       prompt "EFI RCI Table Version 2 Support" if X86 || COMPILE_TEST
> >
> > Why the split of bool and prompt?
> > Why not simply add a single line "depends on X86 || COMPILE_TEST"?
>
> It is because of the findings shared in [1]. Please let me know your
> thoughts on the findings.

So you want to prevent the user from seeing a prompt for an option he may
or may not need to enable, when running "make oldconfig"?

One common approach is to let the Kconfig symbol for the platform (not for
all of X86!) select EFI_RCI2_TABLE.
That way it will be enabled automatically when needed.

Another approach is to not force the option on, but guide the user towards
enabling it, by adding "default y if <platform_symbol>".

> > > > You can drop the || COMPILE_TEST as well.
> > >
> > > I will drop this part of the change in the next version of the patch.
> >
> > Why drop that part? Isn't it good to have more compile test coverage?
>
> It is per the suggestion in the previous review comment.
>
> Ard, please share your thought here. I could add the || COMPILE_TEST.

Without the "|| COMPILE_TEST", you cannot enable compile-testing of
the driver on non-x86 platforms with EFI.

> [1]  Re: [PATCH 4/5] efi: Export Runtime Configuration Interface table to sysfs
> https://lore.kernel.org/linux-efi/20190812150452.27983-1-ard.biesheuvel@linaro.org/T/#mebff9ba48499808f59b33b2daef2d94e006296d8

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds