pata_via: disable ATAPI DMA on AVERATEC 3200

On AVERATEC 3200, pata_via causes memory corruption with ATAPI DMA,
which often leads to random kernel oops.  The cause of the problem is
not well understood yet and only small subset of machines using the
controller seem affected.  Blacklist ATAPI DMA on the machine.
Signed-off-by: Tejun Heo <tj@kernel.org>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=11426Reported-and-tested-by: Jim Bray <jimsantelmo@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

drivers/ata/pata_via.c

@@ -124,6 +124,17 @@ static const struct via_isa_bridge {
 	{ NULL }
 };
 
+static const struct dmi_system_id no_atapi_dma_dmi_table[] = {
+	{
+		.ident = "AVERATEC 3200",
+		.matches = {
+			DMI_MATCH(DMI_BOARD_VENDOR, "AVERATEC"),
+			DMI_MATCH(DMI_BOARD_NAME, "3200"),
+		},
+	},
+	{ }
+};
+
 struct via_port {
 	u8 cached_device;
 };
@@ -355,6 +366,13 @@ static unsigned long via_mode_filter(struct ata_device *dev, unsigned long mask)
 			mask &= ~ ATA_MASK_UDMA;
 		}
 	}
+
+	if (dev->class == ATA_DEV_ATAPI &&
+	    dmi_check_system(no_atapi_dma_dmi_table)) {
+		ata_dev_warn(dev, "controller locks up on ATAPI DMA, forcing PIO\n");
+		mask &= ATA_MASK_PIO;
+	}
+
 	return mask;
 }