Re: [PATCH printk v1 13/13] console: introduce CON_MIGHT_SLEEP for vt

[Greg Kroah-Hartman]

On Wed, Feb 23, 2022 at 02:37:55PM +0100, Petr Mladek wrote:
> On Mon 2022-02-07 20:49:23, John Ogness wrote:
> > Deadlocks and the framebuffer console have been a recurring issue
> > that is getting worse. Daniel Vetter suggested [0] that
> > fbcon->write() should no longer be called from an atomic context.
> 
> We should make it clear that people will not longer see kernel
> messages on ttyX during early boot, panic, and in some other
> situations when printk kthreads are not available.
> 
> Or do I miss something?
> 
> Do we really want this?
> 
> Do the tty maintainers really want to give up on supporting
> modes when processes/kthreads do not work?

I would love that, but:

> Maybe, it is inevitable. Maybe, people are not using tty
> for debugging too much.

People are using tty consoles for debugging all the time.  We can not
break that.

thanks,

greg k-h