summaryrefslogtreecommitdiff
path: root/drivers/ata/libata-core.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/ata/libata-core.c')
-rw-r--r--drivers/ata/libata-core.c6
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 77138a39eb04..83728a9457ad 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -870,7 +870,11 @@ static unsigned int ata_id_xfermask(const u16 *id)
* the PIO timing number for the maximum. Turn it into
* a mask.
*/
- pio_mask = (2 << (id[ATA_ID_OLD_PIO_MODES] & 0xFF)) - 1 ;
+ u8 mode = id[ATA_ID_OLD_PIO_MODES] & 0xFF;
+ if (mode < 5) /* Valid PIO range */
+ pio_mask = (2 << mode) - 1;
+ else
+ pio_mask = 1;
/* But wait.. there's more. Design your standards by
* committee and you too can get a free iordy field to