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Subject[110/114] USB: xhci: Remove buggy assignment in next_trb()
2.6.35-stable review patch.  If anyone has any objections, please let us know.


From: John Youn <>

commit a1669b2c64a9c8b031e0ac5cbf2692337a577f7c upstream.

The code to increment the TRB pointer has a slight ambiguity that could
lead to a bug on different compilers. The ANSI C specification does not
specify the precedence of the assignment operator over the postfix
operator. gcc 4.4 produced the correct code (increment the pointer and
assign the value), but a MIPS compiler that one of John's clients used
assigned the old (unincremented) value.

Remove the unnecessary assignment to make all compilers produce the
correct assembly.

Signed-off-by: John Youn <>
Signed-off-by: Sarah Sharp <>
Signed-off-by: Greg Kroah-Hartman <>

drivers/usb/host/xhci-ring.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -131,7 +131,7 @@ static void next_trb(struct xhci_hcd *xh
*seg = (*seg)->next;
*trb = ((*seg)->trbs);
} else {
- *trb = (*trb)++;
+ (*trb)++;

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