diff options
author | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 15:01:14 -0400 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 20:30:24 -0400 |
commit | bb3207863014c7310593146f11fbc6573eab43c8 (patch) | |
tree | d54da64e459d28969cdd9250cadaaa581cbae43d /drivers/dma/ioat/dma_v2.c | |
parent | 4fb9b9e8d55880523db550043dfb204696dd0422 (diff) |
ioat: ignore reserved bits for chancnt and xfercap
Don't trust that the reserved bits are always zero, also sanity check
the returned value.
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma/ioat/dma_v2.c')
-rw-r--r-- | drivers/dma/ioat/dma_v2.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c index ca1134249341..137cf879265f 100644 --- a/drivers/dma/ioat/dma_v2.c +++ b/drivers/dma/ioat/dma_v2.c | |||
@@ -359,7 +359,14 @@ static int ioat2_enumerate_channels(struct ioatdma_device *device) | |||
359 | 359 | ||
360 | INIT_LIST_HEAD(&dma->channels); | 360 | INIT_LIST_HEAD(&dma->channels); |
361 | dma->chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET); | 361 | dma->chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET); |
362 | dma->chancnt &= 0x1f; /* bits [4:0] valid */ | ||
363 | if (dma->chancnt > ARRAY_SIZE(device->idx)) { | ||
364 | dev_warn(dev, "(%d) exceeds max supported channels (%zu)\n", | ||
365 | dma->chancnt, ARRAY_SIZE(device->idx)); | ||
366 | dma->chancnt = ARRAY_SIZE(device->idx); | ||
367 | } | ||
362 | xfercap_log = readb(device->reg_base + IOAT_XFERCAP_OFFSET); | 368 | xfercap_log = readb(device->reg_base + IOAT_XFERCAP_OFFSET); |
369 | xfercap_log &= 0x1f; /* bits [4:0] valid */ | ||
363 | if (xfercap_log == 0) | 370 | if (xfercap_log == 0) |
364 | return 0; | 371 | return 0; |
365 | dev_dbg(dev, "%s: xfercap = %d\n", __func__, 1 << xfercap_log); | 372 | dev_dbg(dev, "%s: xfercap = %d\n", __func__, 1 << xfercap_log); |