Re: [PATCH v4] xen/common: add keyhandler to show Xen command line

On 11.08.2026 23:09, [email protected] wrote:
> @@ -505,6 +506,37 @@ static int __init cf_check param_init(void)
>  __initcall(param_init);
>  #endif
>  
> +static void cf_check show_cmdline(unsigned char key)
> +{
> +    const char *builtin_cmdline = CONFIG_CMDLINE;

Maybe compilers manage to optimize this to the equivalent of

    static const char builtin_cmdline[] = CONFIG_CMDLINE;

yet even then I see no reason why it wouldn't want spelling that way anyway.

Plus this raises the question: Why would we need two instances of the string
in the Xen image? If you need the literal at runtime, re-use
opt_builtin_cmdline[] by dropping __initconst from it.

> +    const char *cmdline;
> +
> +    printk("'%c' pressed -> showing hypervisor command line\n", key);
> +
> +    if ( builtin_cmdline[0] )
> +        cmdline = builtin_cmdline;
> +    else
> +        cmdline = "<NULL>";
> +
> +    printk("Built-in command line: %s\n", cmdline);

What use is this line when <NULL> is shown?

Jan