From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50242) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1daMDv-0007tk-S8 for qemu-devel@nongnu.org; Wed, 26 Jul 2017 09:19:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1daMDr-0003Cu-TF for qemu-devel@nongnu.org; Wed, 26 Jul 2017 09:19:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44828) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1daMDr-0003Cm-MC for qemu-devel@nongnu.org; Wed, 26 Jul 2017 09:19:31 -0400 Date: Wed, 26 Jul 2017 16:19:24 +0300 From: "Michael S. Tsirkin" Message-ID: <20170726161840-mutt-send-email-mst@kernel.org> References: <20170726093136.13627-1-pbonzini@redhat.com> <20170726155118-mutt-send-email-mst@kernel.org> <20170726130713.GL7620@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170726130713.GL7620@redhat.com> Subject: Re: [Qemu-devel] [qemu PATCH for 2.10] i386: acpi: provide an XSDT instead of an RSDT List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: Paolo Bonzini , phil@philjordan.eu, seabios@seabios.org, qemu-devel@nongnu.org, programmingkidx@gmail.com, Kevin O'Connor , kraxel@redhat.com, lists@philjordan.eu, imammedo@redhat.com, lersek@redhat.com On Wed, Jul 26, 2017 at 02:07:13PM +0100, Daniel P. Berrange wrote: > On Wed, Jul 26, 2017 at 03:52:43PM +0300, Michael S. Tsirkin wrote: > > On Wed, Jul 26, 2017 at 11:31:36AM +0200, Paolo Bonzini wrote: > > > The tables that QEMU provides are not ACPI 1.0 compatible since commit > > > 77af8a2b95 ("hw/i386: Use Rev3 FADT (ACPI 2.0) instead of Rev1 to improve > > > guest OS support.", 2017-05-03). This is visible with Windows 2000, > > > which refuses to parse the rev3 FADT and fails to boot. > > > > > > The recommended solution in this case is to build two FADTs, v1 being > > > pointed to by the RSDT and v3 by the XSDT. However, we leave this task > > > to the firmware. This patch simply switches the RSDT to the XSDT, which > > > is valid for all ACPI 2.0-friendly operating systems and also leaves > > > SeaBIOS the freedom to build an RSDT that points to the compatibility > > > FADT. > > > > > > When running Windows 2000 with an old BIOS, Windows would simply fall > > > back to a non-ACPI HAL; however, the plan should be to include a BIOS with > > > the new feature in 2.10. > > > > > > Reported-by: Programmingkid > > > Signed-off-by: Paolo Bonzini > > > > I'm not against this but let's do it for q35 only please. PC is a legacy > > machine type and let's just leave it alone. > > We've already touched the PC machine type in 77af8a2b95 and that needs > fixing to deal with the regressions it caused. Even if you call it > "legacy", the PC machine is used by the vast majority of deployments > that exist today & likely to be done for the foreseeable future too. > > Regards, > Daniel Fine. So let's avoid making cosmetic changes there. Keep working things working. > -- > |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| > |: https://libvirt.org -o- https://fstop138.berrange.com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|