xhci: Fix an error in count_sg_trbs_needed()
authorPaul Zimmerman <Paul.Zimmerman@synopsys.com>
Sat, 12 Feb 2011 22:07:57 +0000 (14:07 -0800)
committerGreg Kroah-Hartman <gregkh@suse.de>
Mon, 7 Mar 2011 23:05:13 +0000 (15:05 -0800)
commit929364a96776f45edc9b1d71680bf87852dfc39b
tree93d194c8850a668dc7d5af764aaca621b538c189
parent286681ef90a00ad6fdab8d47ac794d1f59004305
xhci: Fix an error in count_sg_trbs_needed()

commit bcd2fde05341cef0052e49566ec88b406a521cf3 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/host/xhci-ring.c