Re: [Qemu-devel] Re: POST failure (loop) with isapc and seabios

[Sebastian Herbszt]

Gleb Natapov wrote:
> On Fri, Nov 20, 2009 at 05:51:13PM -0500, Kevin O'Connor wrote:
> > On Thu, Nov 19, 2009 at 10:30:20PM +0100, Sebastian Herbszt wrote:
> > > i386-softmmu/qemu -M isapc -bios pc-bios/bios.bin
> >
> > Thanks for reporting this.
> >
> > After compiling seabios with CONFIG_DEBUG_SERIAL set in src/config.h
> > and running:
> >
> > qemu -M isapc -serial file:foo
> >
> > I see:
> >
> > Unable to unlock ram - bridge not found
> >
> > SeaBIOS stores global variables in the f-segment.  This greatly
> > simplifies the code, but it does require the ability to write to the
> > f-segment.  Since the f-segment can't be unlocked in "isapc" mode, the
> > boot fails.
> >
> > I'm not really sure what to do about this.  Maybe some kind of non-pci
> > method of unlocking the f-segment could be implemented.
> >
> > Anthony, what do you think?
> May be make qemu to map it writable if isapc is specified.

I don't think keeping the segment writable after POST is a good idea.

- Sebastian