From 509426bd46ad0903dca409803e0ee3d30f99f1e8 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Sun, 20 Dec 2009 19:22:33 +0100 Subject: [PATCH] pata_cmd64x: fix overclocking of UDMA0-2 modes adev->dma_mode stores the transfer mode value not UDMA mode number so the condition in cmd64x_set_dmamode() is always true and the higher UDMA clock is always selected. This can potentially result in data corruption when UDMA33 device is used, when 40-wire cable is used or when the error recovery code decides to lower the device speed down. The issue was introduced in the commit 6a40da0 ("libata cmd64x: whack into a shape that looks like the documentation") which goes back to kernel 2.6.20. Cc: stable@kernel.org Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Jeff Garzik --- drivers/ata/pata_cmd64x.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/ata/pata_cmd64x.c b/drivers/ata/pata_cmd64x.c index 58c09e223838..0efb1f58f255 100644 --- a/drivers/ata/pata_cmd64x.c +++ b/drivers/ata/pata_cmd64x.c @@ -219,7 +219,7 @@ static void cmd64x_set_dmamode(struct ata_port *ap, struct ata_device *adev) regU |= udma_data[adev->dma_mode - XFER_UDMA_0] << shift; /* Merge the control bits */ regU |= 1 << adev->devno; /* UDMA on */ - if (adev->dma_mode > 2) /* 15nS timing */ + if (adev->dma_mode > XFER_UDMA_2) /* 15nS timing */ regU |= 4 << adev->devno; } else { regU &= ~ (1 << adev->devno); /* UDMA off */