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>
Wed, 2 Mar 2011 14:47:07 +0000 (09:47 -0500)
commitcbc0238c26e7a18eff2892ab9a24fa8eed5dc333
tree2698b76e4c3d2944ac0b975d2b2c9f757ec888e8
parent96b51bee08cf97fdc5cdd0bb07dd30b3fe2f57e5
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