From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:45534) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RIcAb-0002Pk-ID for qemu-devel@nongnu.org; Tue, 25 Oct 2011 04:15:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RIcAa-0003ui-Es for qemu-devel@nongnu.org; Tue, 25 Oct 2011 04:15:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58848) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RIcAa-0003uT-6R for qemu-devel@nongnu.org; Tue, 25 Oct 2011 04:15:36 -0400 Message-ID: <4EA67022.3010800@redhat.com> Date: Tue, 25 Oct 2011 10:15:30 +0200 From: Avi Kivity MIME-Version: 1.0 References: <1319480506.8603.54.camel@localhost> In-Reply-To: <1319480506.8603.54.camel@localhost> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Windows 98 installer List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Michael Karcher Cc: qemu-devel@nongnu.org On 10/24/2011 08:21 PM, Michael Karcher wrote: > If you know the 8086 architecture by heart, and also know the qemu code, > you could get the idea that there might be an emulation bug causing the > premature acceptance of the second interrupt (would it be accepted after > cleaning up the stack frames, there would be no problem), namely that > after an IRET or STI instruction, interrupts are only accepted after one > further instruction - and only if they are still enabled. This is true for STI (and only if interrupts were previously disabled), not IRET. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.