diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c
index 68013f9..05e0ffa 100644
--- a/drivers/ata/ata_piix.c
+++ b/drivers/ata/ata_piix.c
@@ -1552,6 +1552,41 @@ static bool piix_broken_system_poweroff(struct pci_dev *pdev)
 	return false;
 }
 
+static int prefer_ms_hyperv = 1;
+module_param(prefer_ms_hyperv, int, 0);
+
+static void piix_ignore_devices_quirk(struct ata_host *host)
+{
+	static const struct dmi_system_id ignore_devices[] = {
+		{
+			/* On Hyper-V hypervisors the disks are exposed on
+			 * both the emulated SATA controller and on the
+			 * paravirtualised drivers.  The CD/DVD devices
+			 * are only exposed on the emulated controller.
+			 * Request we * ignore ATA devices on this host.
+			 */
+			.ident = "Hyper-V Virtual Machine",
+			.matches = {
+				DMI_MATCH(DMI_SYS_VENDOR,
+						"Microsoft Corporation"),
+				DMI_MATCH(DMI_PRODUCT_NAME, "Virtual Machine"),
+			},
+			.driver_data = (void *)ATA_HOST_IGNORE_ATA,
+		},
+
+		{ }	/* terminate list */
+	};
+	const struct dmi_system_id *dmi = dmi_first_match(ignore_devices);
+
+	if (dmi) {
+		unsigned long flags = (unsigned long)dmi->driver_data;
+
+		host->flags |= flags;
+		dev_info(host->dev, "%s detected, device ignore set %08lx\n",
+			dmi->ident, flags);
+	}
+}
+
 /**
  *	piix_init_one - Register PIIX ATA PCI device with kernel services
  *	@pdev: PCI device to register
@@ -1667,6 +1702,9 @@ static int __devinit piix_init_one(struct pci_dev *pdev,
 	}
 	host->flags |= ATA_HOST_PARALLEL_SCAN;
 
+	/* Allow hosts to specify device types to ignore when scanning. */
+	piix_ignore_devices_quirk(host);
+
 	pci_set_master(pdev);
 	return ata_pci_sff_activate_host(host, ata_bmdma_interrupt, sht);
 }