[SeaBIOS] [PATCH] If an int 1587 call is made from an option rom, stay in bigreal mode.

[Kevin O'Connor]

On Sun, Apr 20, 2014 at 01:16:29AM +0200, Paul Menzel wrote:
> Am Samstag, den 19.04.2014, 12:30 -0400 schrieb Kevin O'Connor:
> > Modify the int 1587 handler to check if the POST phase is still
> > running.  If it is, use bigreal mode segment limits so that the caller
> > remains in bigreal mode when the 1587 handler completes.  This helps
> > with SeaVGABIOS' use of "direct" framebuffer accesses (an option rom
> > may attempt to display text during its option rom execution which can
> > cause SeaVGABIOS to make the int 1587 calls).
> 
> Did you experience this or is that just a precaution? If you did
> experience this, could you please elaborate what hardware you used and
> which Option ROMs were executed?

Gerd reported the problem at:

http://www.seabios.org/pipermail/seabios/2014-April/007853.html

This was experienced on QEMU with iPXE.  The problem is generic enough
that it could occur on any hardware and with any option rom that
writes to the screen.

-Kevin