Re: [PATCH -mm] swsusp/pm: refuse to suspend devices if wrong console is active

[Andrew Morton <akpm@osdl.org>]

"Rafael J. Wysocki" <rjw@sisk.pl> wrote:
>
> 1) Remove the console-switching code from the suspend part of the swsusp
> userland interface and let the userland tools switch the console.
> 
> 2) It is unsafe to suspend devices if the hardware is controlled by X.  Add
> an extra check to prevent this from happening.
> 
> ...
> @@ -82,6 +85,12 @@ int device_suspend(pm_message_t state)
>  {
>  	int error = 0;
>  
> +	/* It is unsafe to suspend devices while X has control of the
> +	 * hardware. Make sure we are running on a kernel-controlled console.
> +	 */
> +	if (vc_cons[fg_console].d->vc_mode != KD_TEXT)
> +		return -EINVAL;
> +
>  	down(&dpm_sem);

Does this mean that swsusp simply won't work if invoked while X is running
and being displayed?  If so, that sounds like a pretty severe limitation.