From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1In382-0005Ly-To for qemu-devel@nongnu.org; Tue, 30 Oct 2007 22:16:22 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1In37z-0005J6-Ew for qemu-devel@nongnu.org; Tue, 30 Oct 2007 22:16:22 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1In37z-0005Iu-BQ for qemu-devel@nongnu.org; Tue, 30 Oct 2007 22:16:19 -0400 Received: from nf-out-0910.google.com ([64.233.182.187]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1In37y-0005y3-V1 for qemu-devel@nongnu.org; Tue, 30 Oct 2007 22:16:19 -0400 Received: by nf-out-0910.google.com with SMTP id 30so1938255nfu for ; Tue, 30 Oct 2007 19:16:18 -0700 (PDT) Message-ID: Date: Wed, 31 Oct 2007 03:16:17 +0100 From: "andrzej zaborowski" Subject: Re: [Qemu-devel] [PATCH]bug fix for softmmu slow_st unaligned access In-Reply-To: <13449885.post@talk.nabble.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <13449885.post@talk.nabble.com> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Hi, On 28/10/2007, TeLeMan wrote: > For example, the memory address 0x10008000 is on an unwritable page.When the > instruction "add dword ptr [0x10007FFF],0x12345678" is executed,the OS will > set 0x10008000 page be a writable page and re-execute this instruction. But > softmmu has modifed the value of 0x10007FFF,so after re-executing this > instruction, the final result is wrong(double-added on 0x10007FFF). > Reversing the stored byte order can fix this bug. I'm not sure I understand, but what happens if now the 10008000 page is writable and 10007fff isn't, thus the OS needs to make it writable and re-execute? I guess reversing the accesses order is not a solution? Regards, Andrew