Re: [PATCH] pinctrl: Don't allow PINCTRL_AMD to be a module

From: Hans de Goede
Date: Wed Jul 13 2022 - 17:25:01 EST


Hi,

On 7/13/22 19:59, Mario Limonciello wrote:
> It was observed that by allowing pinctrl_amd to be loaded
> later in the boot process that interrupts sent to the GPIO
> controller early in the boot are not serviced. The kernel treats
> these as a spurious IRQ and disables the IRQ.
>
> This problem was exacerbated because it happened on a system with
> an encrypted partition so the kernel object was not accesssible for
> an extended period of time while waiting for a passphrase.
>
> To avoid this situation from occurring, stop allowing pinctrl-amd
> from being built as a module and instead require it to be built-in
> or disabled.
>
> Reported-by: madcatx@xxxxxxxx
> Suggested-by: jwrdegoede@xxxxxxxxxxxxxxxxx

Note I generally use: "Hans de Goede <hdegoede@xxxxxxxxxx>" for all
things kernel related.

This looks good to me. Fedora is already building in amd-pinctrl
which AFAIK is done because of similar issues to the reason given
in the commit message:

Acked-by: Hans de Goede <hdegoede@xxxxxxxxxx>

Regards,

Hans



> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216230
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> drivers/pinctrl/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
> index f52960d2dfbe..bff144c97e66 100644
> --- a/drivers/pinctrl/Kconfig
> +++ b/drivers/pinctrl/Kconfig
> @@ -32,7 +32,7 @@ config DEBUG_PINCTRL
> Say Y here to add some extra checks and diagnostics to PINCTRL calls.
>
> config PINCTRL_AMD
> - tristate "AMD GPIO pin control"
> + bool "AMD GPIO pin control"
> depends on HAS_IOMEM
> depends on ACPI || COMPILE_TEST
> select GPIOLIB