Le Tue, Feb 21, 2023 at 10:00:10AM -0400, Jared McNeill a écrit :
> Yeah sorry you can?t just not exit boot services and boot the OS. UEFI code
> has certain expectations around the execution environment (MMU on, 1:1 PA to
> VA for example) that starting the kernel is going to interfere with. The
> moment the kernel touches the MMU, all of the resident UEFI code will cease
> to function. This includes code that may be running asynchronously (timers
> etc) that are not stopped properly due to the missing ExitBootServices call.
>
FWIW, having followed EDK II development list for a while, there are
further modifications at the moment made because a lot of people are
focusing on VMs (there is quite a market on this) and want to use
EDK II UEFI code as emulated BIOS. And it must be noted that qemu seems
to be the main target.
Just a caveats for the braves who want to follow this...
T. Laronde
>
> > On Feb 21, 2023, at 9:46 AM, Emmanuel Dreyfus <m...@netbsd.org> wrote:
> >
> > ?On Tue, Feb 21, 2023 at 08:05:00AM -0400, Jared McNeill wrote:
> >> After calling ExitBootServices(), the only things that work are UEFI
> >> runtime
> >> services. You'll have to find another way to print to the console.
> >
> > I can skip the ExitBootServices call and keep printing, I have already
> > done thatn at least in C functions. I have no experience of doing that
> > from assembly code.
> >
> > The same bug exists with a XEN3_DOM0 kernel. Xen starts up, and the
> > kernel crash without displaying anything. I wonder if there are tools
> > to trace the dom0 with help from Xen.
> >
> > --
> > Emmanuel Dreyfus
> > m...@netbsd.org
>
--
Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
http://www.kergis.com/
http://kertex.kergis.com/
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