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staging: comedi: jr3_pci: cope with jiffies wraparound

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The timer expiry routine `jr3_pci_poll_dev()` checks for expiry by
checking whether the absolute value of `jiffies` (stored in local
variable `now`) is greater than the expected expiry time in jiffy units.
This will fail when `jiffies` wraps around.  Also, it seems to make
sense to handle the expiry one jiffy earlier than the current test.  Use
`time_after_eq()` to check for expiry.

Cc: <stable@vger.kernel.org> # 3.15+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ian Abbott 2017-02-17 11:09:09 +00:00 committed by Greg Kroah-Hartman
parent 45292be0b3
commit 8ec04a4918
1 changed files with 1 additions and 1 deletions
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drivers/staging/comedi/drivers/jr3_pci.c
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@ -611,7 +611,7 @@ static void jr3_pci_poll_dev(unsigned long data)
s = &dev->subdevices[i];
spriv = s->private;
if (now > spriv->next_time_min) {
if (time_after_eq(now, spriv->next_time_min)) {
struct jr3_pci_poll_delay sub_delay;
sub_delay = jr3_pci_poll_subdevice(s);