From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54003) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1abQBh-0001v7-4o for qemu-devel@nongnu.org; Thu, 03 Mar 2016 05:08:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1abQBc-0004JI-5r for qemu-devel@nongnu.org; Thu, 03 Mar 2016 05:08:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57011) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1abQBc-0004JD-03 for qemu-devel@nongnu.org; Thu, 03 Mar 2016 05:08:48 -0500 References: <1456983051-14707-1-git-send-email-rth@twiddle.net> <1456983051-14707-5-git-send-email-rth@twiddle.net> <56D7E054.2040703@reactos.org> From: Paolo Bonzini Message-ID: <56D80D2C.3060706@redhat.com> Date: Thu, 3 Mar 2016 11:08:44 +0100 MIME-Version: 1.0 In-Reply-To: <56D7E054.2040703@reactos.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 4/7] target-i386: Dump illegal opcodes with -d unimp List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?Q?Herv=c3=a9_Poussineau?= , Richard Henderson , qemu-devel@nongnu.org > Do you want LOG_UNIMP or LOG_GUEST_ERROR?=20 I would actually use LOG_IN_ASM. As you noticed, guests sometimes use illegal opcodes; another example is Xen's hypercall interface. On 03/03/2016 07:57, Herv=E9 Poussineau wrote: > This patch is not quiet on some operating systems: > OS/2: > ILLOPC: 000172e1: 0f a6 >=20 > Windows XP: > ILLOPC: 00020d1a: c4 c4 >=20 > And very verbose in Windows 3.11, Windows 9x: > ILLOPC: 000ffb17: 63 > ILLOPC: 000ffb17: 63 >=20 > Is it normal? Yes, it is. As usual, Raymond Chen explains what's going on: https://blogs.msdn.microsoft.com/oldnewthing/20041215-00/?p=3D37003 Alternatively, you can buy Unauthorized Windows 95 on Amazon for about 10 euros. Which of course I just did. :) Paolo