From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46110) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WX52f-0001iA-8A for qemu-devel@nongnu.org; Mon, 07 Apr 2014 04:36:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WX52Y-0006v1-Dj for qemu-devel@nongnu.org; Mon, 07 Apr 2014 04:36:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:28287) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WX52Y-0006up-3y for qemu-devel@nongnu.org; Mon, 07 Apr 2014 04:36:26 -0400 Date: Mon, 7 Apr 2014 11:36:05 +0300 From: "Michael S. Tsirkin" Message-ID: <20140407083605.GA14073@redhat.com> References: <1396776125-5419-1-git-send-email-mst@redhat.com> <20140407094634.31281c8b@nial.usersys.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20140407094634.31281c8b@nial.usersys.redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH for-2.0] dsdt: tweak ACPI ID for hotplug resource device List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov Cc: qemu-devel@nongnu.org, Anthony Liguori On Mon, Apr 07, 2014 at 09:46:34AM +0200, Igor Mammedov wrote: > On Sun, 6 Apr 2014 12:47:37 +0300 > "Michael S. Tsirkin" wrote: >=20 > > ACPI0004 seems too new: > > Windows XP complains about an unrecognized device. > > This is a regression since 1.7. > > Use PNP0A06 instead - Generic Container Device. > >=20 > > Signed-off-by: Michael S. Tsirkin > > --- > >=20 > > Note: Igor has RFC patches to use PNP0C02 under PCI0, > > but that's not ready for 2.0. > > Igor, could you comment on whether PNP0C02 is preferable for > > some OS-es? > >=20 > > For PNP0A06 ACPI spec says: > > PNP0A06 > > Generic Container Device. This device behaves exactly the same as= the > > PNP0A05 device. > > This was originally known as Extended I/O Bus. This ID should onl= y be > > used for containers > > that do not produce resources for consumption by child devices. A= ny > > system resources > > claimed by a PNP0A06 device=E2=80=99s _CRS object must be consume= d by the > > container itself. > >=20 > > PNP0C02 is not in ACPI spec. It does appear in MicroSoft legacy PNP I= D > > document: > > PNP0C02 General ID for reserving resources required by Pl= ug and > > Play motherboard registers. (Not specific to a particular device.= ) > >=20 > > Thoughts? > From testing Windows doesn't check for conflicts _CRS provided by PNP0C= 02, > so while using it will let XP not to complain about unknown device, it = will > also make later Windows OSes silently ignore conflicts if any. >=20 > When XP's complaining for the first time about unknown device, it could= be > told to ignore it, so it would stop to complain in future. i.e. user ha= ve to > silence only once. >=20 > Wouldn't it be better to use ACPI0004 that gives minor annoyance to XP = user > but provides error checking with later OS versions? OK I quickly tested with Win7 and it does check for conflicts when EisaId("PNP0A06") is used. Taking this into account, ack this patch? > >=20 > > hw/i386/acpi-dsdt-cpu-hotplug.dsl | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > >=20 > > diff --git a/hw/i386/acpi-dsdt-cpu-hotplug.dsl b/hw/i386/acpi-dsdt-cp= u-hotplug.dsl > > index dee4843..34aab5a 100644 > > --- a/hw/i386/acpi-dsdt-cpu-hotplug.dsl > > +++ b/hw/i386/acpi-dsdt-cpu-hotplug.dsl > > @@ -93,7 +93,7 @@ Scope(\_SB) { > > } > > =20 > > Device(CPU_HOTPLUG_RESOURCE_DEVICE) { > > - Name(_HID, "ACPI0004") > > + Name(_HID, EisaId("PNP0A06")) > > =20 > > Name(_CRS, ResourceTemplate() { > > IO(Decode16, CPU_STATUS_BASE, CPU_STATUS_BASE, 0, CPU_ST= ATUS_LEN)