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Date: Sun, 13 Jun 2004 15:22:08 +0200
From: Fabrice Bellard <fabrice@bellard.org>
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Subject: Re: [Qemu-devel] Wrong Exception - should have GPF instead of PF
	for	NULL selector
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To: qemu-devel@nongnu.org

Antony T Curtis wrote:
> I have been looking at why OS/2 Warp Connect fails to start Presentation
> Manager under QEMU and I have found the following...
> 
> We get a Page Fault when QEMU encounters the following instruction
> 
> 0xfe0a9971:  mov    %es:(%si),%ebx
> 
> Where ES=0x0000 and ESI=0xabde0000
> 
> This should generate a General Protection exception as we are accessing
> memory using a NULL selector
> 
> I don't know if it would fix OS/2 but it is definitely behaviour which
> is 'not correct'.

OK, it is not correct, but it is not the cause of the problem: I tried 
to generate a GPF and I have the same bug. Moreover, I looked at the 
code before and %es is really set to zero...

Fabrice.