From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54986) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bLesC-00060e-S2 for qemu-devel@nongnu.org; Fri, 08 Jul 2016 19:07:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bLes8-0003y8-R8 for qemu-devel@nongnu.org; Fri, 08 Jul 2016 19:07:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56270) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bLes8-0003xu-Ls for qemu-devel@nongnu.org; Fri, 08 Jul 2016 19:07:48 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4DF237AE85 for ; Fri, 8 Jul 2016 23:07:48 +0000 (UTC) Date: Fri, 8 Jul 2016 16:50:57 -0300 From: Eduardo Habkost Message-ID: <20160708195057.GP4131@thinpad.lan.raisama.net> References: <1467990099-27853-1-git-send-email-dgilbert@redhat.com> <1467990099-27853-3-git-send-email-dgilbert@redhat.com> <20160708185932.GO4131@thinpad.lan.raisama.net> <20160708192532.GC2833@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160708192532.GC2833@work-vm> Subject: Re: [Qemu-devel] [PATCH v4 2/5] x86: Allow physical address bits to be set List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert" Cc: qemu-devel@nongnu.org, pbonzini@redhat.com, marcel@redhat.com, mst@redhat.com, kraxel@redhat.com On Fri, Jul 08, 2016 at 08:25:32PM +0100, Dr. David Alan Gilbert wrote: > > > + return; > > > + } > > > > > > + if (env->features[FEAT_1_EDX] & CPUID_PSE36) { > > > + cpu->phys_bits = 36; > > > + } else { > > > + cpu->phys_bits = 32; > > > > But TCG_PHYS_ADDR_BITS is still 36. Does this mean TCG > > reserved-bit handling is broken if pse36 is disabled? > > Good question; I don't understand the TCG code enough to comment; > but I'm reasonably sure that this patchset doesn't change the behaviour. > I've booted a 32bit fedora, on a qemu that claims to be running > with phys_bits = 32 - I don't believe that works on real hardware. > (Mind you booting it on qemu-system-i386 with qemu32 CPU just doesn't > work, but it doesn't work before my patch either). Yes, I was wondering about the existing behavior. You don't change any behavior here, as far as I can see. -- Eduardo