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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH] Revived GUEST_BASE support for usermode
	emulation targets [v3]
Date: Tue, 5 May 2009 14:53:31 +0100
References: <1241028203-19687-1-git-send-email-riku.voipio@iki.fi>
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	<20090505132743.GA29021@kos.to>
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To: qemu-devel@nongnu.org
Cc: mika.westerberg@iki.fi, Riku Voipio <riku.voipio@iki.fi>

On Tuesday 05 May 2009, Riku Voipio wrote:
> +++ b/tcg/x86_64/tcg-target.c
> @@ -616,15 +616,15 @@ static void tcg_out_qemu_ld(TCGContext *s, const
> =A0 =A0 =A0 =A0 =A0/* movzbl */
> - =A0 =A0 =A0 =A0tcg_out_modrm_offset(s, 0xb6 | P_EXT, data_reg, r0, 0);
> + =A0 =A0 =A0 =A0tcg_out_modrm_offset(s, 0xb6 | P_EXT, data_reg, r0, GUES=
T_BASE);

This breaks when GUEST_BASE is large.
32-bit x86 is probably ok because GUEST_BASE is always a 32-bit value. This=
 is=20
not true for x86-64. Incidentally tcg_out_modrm doesn't seem to check this,=
=20
and silently generates broken code.

Paul