diff options
| author | Paul Zimmerman <Paul.Zimmerman@synopsys.com> | 2011-02-12 23:07:57 +0100 |
|---|---|---|
| committer | Sarah Sharp <sarah.a.sharp@linux.intel.com> | 2011-02-20 16:01:28 +0100 |
| commit | bcd2fde05341cef0052e49566ec88b406a521cf3 (patch) | |
| tree | e2d101797ba072dea57c465b47b2892e7e4a19a3 | |
| parent | xhci: Fix errors in the running total calculations in the TRB math (diff) | |
| download | linux-bcd2fde05341cef0052e49566ec88b406a521cf3.tar.xz linux-bcd2fde05341cef0052e49566ec88b406a521cf3.zip | |
xhci: Fix an error in count_sg_trbs_needed()
The expression
while (running_total < sg_dma_len(sg))
does not take into account that the remaining data length can be less
than sg_dma_len(sg). In that case, running_total can end up being
greater than the total data length, so an extra TRB is counted.
Changing the expression to
while (running_total < sg_dma_len(sg) && running_total < temp)
fixes that.
This patch should be queued for stable kernels back to 2.6.31.
Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index dbbeec96ce1d..3289bf4832c9 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2374,7 +2374,7 @@ static unsigned int count_sg_trbs_needed(struct xhci_hcd *xhci, struct urb *urb) num_trbs++; /* How many more 64KB chunks to transfer, how many more TRBs? */ - while (running_total < sg_dma_len(sg)) { + while (running_total < sg_dma_len(sg) && running_total < temp) { num_trbs++; running_total += TRB_MAX_BUFF_SIZE; } |