usb: xhci: address off-by-one in xhci_num_trbs_free()
authorNiklas Neronin <niklas.neronin@linux.intel.com>
Mon, 29 Apr 2024 14:02:32 +0000 (17:02 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 1 May 2024 06:47:14 +0000 (08:47 +0200)
commit5adc1cc038f4446b11dd260e0a848fdeaac12306
tree1499e5033bc3ad9cfda98d7cd50d0ef8e43f2c4e
parent577c867cf8f638b05f5676ed06a1ffe9afbba896
usb: xhci: address off-by-one in xhci_num_trbs_free()

Reduce the number of do-while loops by 1. The number of loops should be
number of segment + 1, the +1 is in case deq and enq are on the same
segment. But due to the use of a do-while loop, the expression is
evaluated after executing the loop, thus the loop is executed 1 extra
time.

Changing the do-while loop expression from "<=" to "<", reduces the loop
amount by 1. The expression "<=" would also work if it was a while loop
instead of a do-while loop.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240429140245.3955523-6-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-ring.c