diff --git a/[refs] b/[refs]
index bdc33d163d9c..39f8826144a6 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c36f74e67fa12202dbcb4ad92c5ac844f9d36b98
+refs/heads/master: dbd004291ed31db280a3f2d7a1113a04e5e85af4
diff --git a/trunk/drivers/ata/ahci.c b/trunk/drivers/ata/ahci.c
index b34390347c16..a6a736a7dbf2 100644
--- a/trunk/drivers/ata/ahci.c
+++ b/trunk/drivers/ata/ahci.c
@@ -3082,8 +3082,16 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	ahci_save_initial_config(pdev, hpriv);
 
 	/* prepare host */
-	if (hpriv->cap & HOST_CAP_NCQ)
-		pi.flags |= ATA_FLAG_NCQ | ATA_FLAG_FPDMA_AA;
+	if (hpriv->cap & HOST_CAP_NCQ) {
+		pi.flags |= ATA_FLAG_NCQ;
+		/* Auto-activate optimization is supposed to be supported on
+		   all AHCI controllers indicating NCQ support, but it seems
+		   to be broken at least on some NVIDIA MCP79 chipsets.
+		   Until we get info on which NVIDIA chipsets don't have this
+		   issue, if any, disable AA on all NVIDIA AHCIs. */
+		if (pdev->vendor != PCI_VENDOR_ID_NVIDIA)
+			pi.flags |= ATA_FLAG_FPDMA_AA;
+	}
 
 	if (hpriv->cap & HOST_CAP_PMP)
 		pi.flags |= ATA_FLAG_PMP;