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

[Gleb Natapov]

On Sun, Nov 22, 2009 at 04:07:56PM +0100, Sebastian Herbszt wrote:
> 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.
> 
Isn't it writable now after POST with pcipc? Why this is not a good
idea?

--
                        Gleb.