[PATCH 1/3] ARM: vexpress_defconfig: Enable and automount devtmpfs filesystem

[pawel.moll@arm.com (Pawel Moll)]

On Tue, 2013-08-20 at 22:02 +0100, Fathi Boudra wrote:
> udev no longer creates device nodes under /dev and it has to be managed
> by the kernel devtmpfs filesystem.
> 
> This means that a kernel built with the current config will not boot on
> a system with a recent udev:
> 
> mount: mounting udev on /dev failed: No such device
> W: devtmpfs not available, falling back to tmpfs for /dev
> 
> Also, it is good to have /dev automatically mounted since some
> non-initramfs based setups assumes this and don't manually mount it.
> 
> Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
> ---
>  arch/arm/configs/vexpress_defconfig | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
> index f2de51f..3f970f1 100644
> --- a/arch/arm/configs/vexpress_defconfig
> +++ b/arch/arm/configs/vexpress_defconfig
> @@ -45,6 +45,8 @@ CONFIG_IP_PNP_BOOTP=y
>  # CONFIG_IPV6 is not set
>  # CONFIG_WIRELESS is not set
>  CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
> +CONFIG_DEVTMPFS=y

This makes sense...

> +CONFIG_DEVTMPFS_MOUNT=y

... but I'm not so sure about this one. Normally it's up to the boot
scripts to decide when to mount the devtmpfs. And yes - I know it's
required to boot Ubuntu-based rootfs without initramfs, but that's
Ubuntu's problem, really.

>  CONFIG_MTD=y
>  CONFIG_MTD_CONCAT=y
>  CONFIG_MTD_PARTITIONS=y