From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35508) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eFNGl-0000lP-0S for qemu-devel@nongnu.org; Thu, 16 Nov 2017 11:44:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eFNGj-0002vo-V9 for qemu-devel@nongnu.org; Thu, 16 Nov 2017 11:44:03 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35068) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eFNGj-0002uy-ON for qemu-devel@nongnu.org; Thu, 16 Nov 2017 11:44:01 -0500 References: <1510769835-31902-1-git-send-email-mst@redhat.com> <20171116173033-mutt-send-email-mst@kernel.org> <20171116154534.GR16461@redhat.com> <20171116175149-mutt-send-email-mst@kernel.org> <20171116161344.GU16461@redhat.com> From: Thomas Huth Message-ID: Date: Thu, 16 Nov 2017 17:43:52 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PULL 00/10] pc, pci, virtio: fixes for rc1 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell , "Daniel P. Berrange" Cc: QEMU Developers , "Michael S. Tsirkin" On 16.11.2017 17:15, Peter Maydell wrote: > On 16 November 2017 at 16:13, Daniel P. Berrange = wrote: >> On Thu, Nov 16, 2017 at 04:10:22PM +0000, Peter Maydell wrote: >>> If there are known-buggy iasl versions in the wild we could >>> consider a configure test and treat buggy-iasl like no-iasl. >> >> iasl has long been broken on big-endian, but it has also long containe= d >> code that simply makes it exit immediately in that case, and qemu cope= s >> with that. So if there's buggy iasl it would be a distro which removed >> this big-endian check and tried to make it work on big-endian but fail= ed. >> Fedora tried the latter, but at least in rawhide it works properly now= . >> I'm unclear if we shipped broken iasl with the BE check removed in sta= ble >> versions though >=20 > In this case this is Ubuntu 16.04.2 LTS (xenial) on s390x, with >=20 > linux1@lxub05:~$ iasl -v >=20 > Intel ACPI Component Architecture > ASL+ Optimizing Compiler version 20160108-64 > Copyright (c) 2000 - 2016 Intel Corporation That's likely a broken version, indeed. I've noticed that the iasl that ships with the acpica-tools in RHEL7 is broken, too - it does not contain the big-endian check (yet?), and fails to byte-swap on big endian hosts. If you compile the latest version from upstream, you get this instead: $ iasl -v iASL is not currently supported on big-endian machines. But as Daniel already wrote: The version from Fedora contains some patches that fix the endianess issue, so that iasl with these patches also works fine on big endian hosts: https://src.fedoraproject.org/rpms/acpica-tools/blob/master/f/big-endian= .patch https://src.fedoraproject.org/rpms/acpica-tools/blob/master/f/big-endian= -v2.patch Thomas