[ 3.5.y.z extended stable ] Patch "ata_piix: reenable MS Virtual PC guests" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    ata_piix: reenable MS Virtual PC guests

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From d83e45008e537f38ef5b07b19eaa831086002c32 Mon Sep 17 00:00:00 2001
From: Olaf Hering <olaf at aepfle.de>
Date: Tue, 18 Sep 2012 17:48:01 +0200
Subject: [PATCH] ata_piix: reenable MS Virtual PC guests

commit d9904344fc4052fbe7e4dc137eba0dcdadf326bd upstream.

An earlier commit cd006086fa5d91414d8ff9ff2b78fbb593878e3c ("ata_piix:
defer disks to the Hyper-V drivers by default") broke MS Virtual PC
guests. Hyper-V guests and Virtual PC guests have nearly identical DMI
info. As a result the driver does currently ignore the emulated hardware
in Virtual PC guests and defers the handling to hv_blkvsc. Since Virtual
PC does not offer paravirtualized drivers no disks will be found in the
guest.

One difference in the DMI info is the product version. This patch adds a
match for MS Virtual PC 2007 and "unignores" the emulated hardware.

This was reported for openSuSE 12.1 in bugzilla:
https://bugzilla.novell.com/show_bug.cgi?id=737532

Here is a detailed list of DMI info from example guests:

hwinfo --bios:

virtual pc guest:

  System Info: #1
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "VS2005R2"
    Serial: "3178-9905-1533-4840-9282-0569-59"
    UUID: undefined, but settable
    Wake-up: 0x06 (Power Switch)
  Board Info: #2
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "5.0"
    Serial: "3178-9905-1533-4840-9282-0569-59"
  Chassis Info: #3
    Manufacturer: "Microsoft Corporation"
    Version: "5.0"
    Serial: "3178-9905-1533-4840-9282-0569-59"
    Asset Tag: "7188-3705-6309-9738-9645-0364-00"
    Type: 0x03 (Desktop)
    Bootup State: 0x03 (Safe)
    Power Supply State: 0x03 (Safe)
    Thermal State: 0x01 (Other)
    Security Status: 0x01 (Other)

win2k8 guest:

  System Info: #1
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "9106-3420-9819-5495-1514-2075-48"
    UUID: undefined, but settable
    Wake-up: 0x06 (Power Switch)
  Board Info: #2
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "9106-3420-9819-5495-1514-2075-48"
  Chassis Info: #3
    Manufacturer: "Microsoft Corporation"
    Version: "7.0"
    Serial: "9106-3420-9819-5495-1514-2075-48"
    Asset Tag: "7076-9522-6699-1042-9501-1785-77"
    Type: 0x03 (Desktop)
    Bootup State: 0x03 (Safe)
    Power Supply State: 0x03 (Safe)
    Thermal State: 0x01 (Other)
    Security Status: 0x01 (Other)

win2k12 guest:

  System Info: #1
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "8179-1954-0187-0085-3868-2270-14"
    UUID: undefined, but settable
    Wake-up: 0x06 (Power Switch)
  Board Info: #2
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "8179-1954-0187-0085-3868-2270-14"
  Chassis Info: #3
    Manufacturer: "Microsoft Corporation"
    Version: "7.0"
    Serial: "8179-1954-0187-0085-3868-2270-14"
    Asset Tag: "8374-0485-4557-6331-0620-5845-25"
    Type: 0x03 (Desktop)
    Bootup State: 0x03 (Safe)
    Power Supply State: 0x03 (Safe)
    Thermal State: 0x01 (Other)
    Security Status: 0x01 (Other)

Signed-off-by: Olaf Hering <olaf at aepfle.de>
Signed-off-by: Jeff Garzik <jgarzik at redhat.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/ata/ata_piix.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c
index 3c809bf..36b5276 100644
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -1577,12 +1577,31 @@ static void piix_ignore_devices_quirk(struct ata_host *host)
 		},
 		{ }	/* terminate list */
 	};
-	const struct dmi_system_id *dmi = dmi_first_match(ignore_hyperv);
+	static const struct dmi_system_id allow_virtual_pc[] = {
+		{
+			/* In MS Virtual PC guests the DMI ident is nearly
+			 * identical to a Hyper-V guest. One difference is the
+			 * product version which is used here to identify
+			 * a Virtual PC guest. This entry allows ata_piix to
+			 * drive the emulated hardware.
+			 */
+			.ident = "MS Virtual PC 2007",
+			.matches = {
+				DMI_MATCH(DMI_SYS_VENDOR,
+						"Microsoft Corporation"),
+				DMI_MATCH(DMI_PRODUCT_NAME, "Virtual Machine"),
+				DMI_MATCH(DMI_PRODUCT_VERSION, "VS2005R2"),
+			},
+		},
+		{ }	/* terminate list */
+	};
+	const struct dmi_system_id *ignore = dmi_first_match(ignore_hyperv);
+	const struct dmi_system_id *allow = dmi_first_match(allow_virtual_pc);

-	if (dmi && prefer_ms_hyperv) {
+	if (ignore && !allow && prefer_ms_hyperv) {
 		host->flags |= ATA_HOST_IGNORE_ATA;
 		dev_info(host->dev, "%s detected, ATA device ignore set\n",
-			dmi->ident);
+			ignore->ident);
 	}
 #endif
 }
--
1.8.1.2