[PATCH] xen/arm: allow console=hvc0 to be omitted for guests

[Stefano Stabellini]

On Fri, 30 Jan 2015, Ard Biesheuvel wrote:
> This patch registers hvc0 as the preferred console if no console
> has been specified explicitly on the kernel command line.
> 
> The purpose is to allow platform agnostic kernels and boot images
> (such as distro installers) to boot in a Xen/ARM domU without the
> need to modify the command line by hand.
> 
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
> ---
> 
> This applies on top of the patch Julien is cooking up to move the
> call to xen_guest_init() to an earlier boot stage. This needs to
> be at least before the call to console_init() in start_kernel()
> for this patch to do anything meaningful.

This patch looks good but there isn't much point in queuing this up
without the prerequisite.

Julien, what patch exactly is that? What is the status of it?


>  arch/arm/xen/enlighten.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
> index c7ca936ebd99..61382cafa877 100644
> --- a/arch/arm/xen/enlighten.c
> +++ b/arch/arm/xen/enlighten.c
> @@ -24,6 +24,7 @@
>  #include <linux/cpuidle.h>
>  #include <linux/cpufreq.h>
>  #include <linux/cpu.h>
> +#include <linux/console.h>
>  
>  #include <linux/mm.h>
>  
> @@ -322,6 +323,9 @@ static int __init xen_guest_init(void)
>  
>  	register_cpu_notifier(&xen_cpu_notifier);
>  
> +	if (!console_set_on_cmdline)
> +		add_preferred_console("hvc", 0, NULL);
> +
>  	return 0;
>  }
>  early_initcall(xen_guest_init);
> -- 
> 1.8.3.2
>