On 30.03.2023 18:17, Roger Pau Monné wrote: > On Thu, Mar 30, 2023 at 06:07:57PM +0200, Jan Beulich wrote: >> On 30.03.2023 17:44, Roger Pau Monné wrote: >>> I guess I'm slightly confused by the usage of both GOP and StdOut, I >>> would assume if we have a gop, and can correctly initialize it there's >>> no need to fiddle with StdOut also? >> >> Setting the GOP mode is done last before exiting boot services; this >> may be a graphics mode which doesn't support a text output protocol. > > Right, that's what I was missing. I assumed that all modes available > in GOP would be compatible with the ConOut mode. > > Would you be OK with leaving StdOut as-is when booted from multiboot2, > or there's a chance of things not being properly setup?
On modern UEFI it may be unlikely, but I think it's not impossible (see below). > IMO it's not very friendly to change the StdOut mode if not explicitly > requested, as in the multiboot2 case that gets setup by the > bootloader. May get set up, that is. If it was set up, then yes, we probably should leave it alone unless told to use another mode. I.e. no vga= or vga=current should minimally result in no further mode change. Aiui we can't easily honor vga=gfx-... in that case, so leaving the mode alone there may also be better than trying to guess a mode. The only time where I would think it would be nice to switch by default even in the xen.gz case is if the boot loader handed us the screen in some text mode. Jan
