From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39514) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e5AyY-0005GG-Iy for qemu-devel@nongnu.org; Thu, 19 Oct 2017 09:35:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e5AyT-0000tu-IC for qemu-devel@nongnu.org; Thu, 19 Oct 2017 09:35:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33162) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e5AyT-0000ti-D0 for qemu-devel@nongnu.org; Thu, 19 Oct 2017 09:35:01 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 724A4FED4 for ; Thu, 19 Oct 2017 13:35:00 +0000 (UTC) References: <20171018095807.101406-1-marcel@redhat.com> <69cefa98-5681-5b12-719c-e13fcba969c4@redhat.com> <9d4b1fa8-e670-556b-278d-4993ad41b512@redhat.com> <1508418225.18146.1.camel@redhat.com> From: Marcel Apfelbaum Message-ID: Date: Thu, 19 Oct 2017 16:34:46 +0300 MIME-Version: 1.0 In-Reply-To: <1508418225.18146.1.camel@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH] hw/pci-host: Fix x86 Host Bridges 64bit PCI hole List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann , Laszlo Ersek , qemu-devel@nongnu.org Cc: mst@redhat.com, pbonzini@redhat.com, ehabkost@redhat.com, Igor Mammedov , "Dr. David Alan Gilbert" On 19/10/2017 16:03, Gerd Hoffmann wrote: > Hi, >=20 >> =C2=A0 - commit 39848901818 pc: limit 64 bit hole to 2G by default >> =C2=A0 shows us QEMU had the 64bit PCI hole, so it is a regression. >=20 > commit message says: >=20 > > =C2=A0=C2=A0=C2=A0=C2=A0It turns out that some 32 bit windows guests c= rash > =C2=A0=C2=A0=C2=A0=C2=A0if 64 bit PCI hole size is >2G. > >=20 > Why this suddenly isn't a problem any more? >=20 I suppose it is, so we need a way to turn it "off". > Also: how about just using the existing pci_hole64_size property? >=20 This is how I started, however Eduardo and (and maybe Michael ?) where against letting the upper management software to deal with such a low low level detail. They simply can't take such a decision. This is why the property you mentioned is not ever linked in code anywhere! It is simply not implemented and not used. What about renaming the added compat property from x-pci-hole64-fix to pci-hole64? Users using 32-bit Windows guests having the mentioned issue guests will disable it. Thanks, Marcel > cheers, > Gerd >=20