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Date: Fri, 16 Feb 2007 13:17:45 -0500
From: Peter <pjcreath+openbios@gmail.com>
Sender: pjcreath@gmail.com
Subject: Re: [Qemu-devel] Potential sparc32 MMU bug
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To: Paul Brook <paul@codesourcery.com>
Cc: qemu-devel@nongnu.org

It definitely gets blocked by something: if I leave the the trap table
in the .text section, the write silently fails.  If I move the trap
table to the .data section, the write succeeds.  If I move the trap
table over to .rodata, the write fails again.  What are you looking at
that suggests the whole sparc bios is loaded read/write?

On 2/16/07, Paul Brook <paul@codesourcery.com> wrote:
> On Friday 16 February 2007 16:55, Peter wrote:
> > While working on getting SunOS to boot under qemu, I ran into a very
> > odd bug, and I'm not sure whose fault it is.
> >
> > The SunOS bootloader tries to install trap 0 by writing to the trap
> > table.  The trap table is in the .text (read-only) section of the
> > OpenBIOS ROM.
>
> I don't know about sparc, but it's normal for writes to ROM to be ignored.
> However by my reading the sparc bios is loaded into RAM anyway, so it
> shouldn't matter.
>
> Paul
>