3.6-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Aaron Lu <redacted>

commit 60817a680b1bd3341b6909fab7d8a1fcc3a78369 upstream.

commit 6b66d95895c149cbc04d4fac5a2f5477c543a8ae didn't handle SATA PMP
case in ata_acpi_bind_device and will cause a NULL ptr dereference when
user attached a SATA drive to the PMP port. Fix this by checking PMP
support.

This bug is reported by Dan van der Ster in the following bugzilla page:
https://bugzilla.kernel.org/show_bug.cgi?id=48211

Reported-by: Dan van der Ster <redacted>
Tested-by: Dan van der Ster <redacted>
Signed-off-by: Aaron Lu <redacted>
Signed-off-by: Jeff Garzik <redacted>
Tested-by: Simon <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/ata/libata-acpi.c |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c

@@ -1105,10 +1105,15 @@ static int ata_acpi_bind_device(struct a
 	struct acpi_device *acpi_dev;
 	struct acpi_device_power_state *states;
 
-	if (ap->flags & ATA_FLAG_ACPI_SATA)
-		ata_dev = &ap->link.device[sdev->channel];
-	else
+	if (ap->flags & ATA_FLAG_ACPI_SATA) {
+		if (!sata_pmp_attached(ap))
+			ata_dev = &ap->link.device[sdev->id];
+		else
+			ata_dev = &ap->pmp_link[sdev->channel].device[sdev->id];
+	}
+	else {
 		ata_dev = &ap->link.device[sdev->id];
+	}
 
 	*handle = ata_dev_acpi_handle(ata_dev);