Re: [PATCH 1/3] startup: check for console before showing menu

[Sascha Hauer <s.hauer@pengutronix.de>]

On Tue, Oct 28, 2025 at 01:39:22PM +0100, Ahmad Fatoum wrote:
> Hi Fabian,
> 
> On 10/28/25 1:18 PM, Fabian Pflug wrote:
> > If there is no input available or possible due to policy settings, it
> > does not make sense to show a menu and ask for input.
> > 
> > Signed-off-by: Fabian Pflug <f.pflug@pengutronix.de>
> > ---
> >  common/startup.c | 18 ++++++++++--------
> >  1 file changed, 10 insertions(+), 8 deletions(-)
> > 
> > diff --git a/common/startup.c b/common/startup.c
> > index 8d36ffceb4..3bc2609006 100644
> > --- a/common/startup.c
> > +++ b/common/startup.c
> > @@ -45,6 +45,7 @@
> >  #include <pbl/handoff-data.h>
> >  #include <libfile.h>
> >  #include <fuzz.h>
> > +#include <security/config.h>
> >  
> >  extern initcall_t __barebox_initcalls_start[], __barebox_early_initcalls_end[],
> >  		  __barebox_initcalls_end[];
> > @@ -361,14 +362,15 @@ static int run_init(void)
> >  		run_shell();
> >  	}
> >  
> > -	do {
> > -		/*
> > -		 * Let's run the command once at least, so an error
> > -		 * message is printed if the file doesn't exist
> > -		 */
> > -		run_command(MENUFILE);
> > -	} while (stat(MENUFILE, &s) == 0);
> > -
> > +	if(!IS_ENABLED(CONFIG_CONSOLE_DISABLE_INPUT) && IS_ALLOWED(SCONFIG_CONSOLE_INPUT)) {
> 
> CONFIG_CONSOLE_DISABLE_INPUT only influences the default, it can still
> be changed later at runtime, so this is not necessarily correct.

I agree with this. I just noticed we already have this in the code
and we'll want to reconsider this:

        if (IS_ENABLED(CONFIG_NET) && !IS_ENABLED(CONFIG_CONSOLE_DISABLE_INPUT) &&
            autoboot != AUTOBOOT_HALT)
                eth_open_all();

How about replacing the test for CONFIG_CONSOLE_DISABLE_INPUT with a
runtime decision like:

bool console_can_input(void)
{
	struct console_device *cdev;

	if (!IS_ALLOWED(SCONFIG_CONSOLE_INPUT))
		return false;

	for_each_console(cdev) {
                if (cdev->f_active & CONSOLE_STDIN)
                        return true;
        }

	return false;
}

Sascha

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