From 8ec04a491825e08068e92bed0bba7821893b6433 Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Fri, 17 Feb 2017 11:09:09 +0000 Subject: [PATCH] staging: comedi: jr3_pci: cope with jiffies wraparound 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: # 3.15+ Signed-off-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/jr3_pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/staging/comedi/drivers/jr3_pci.c b/drivers/staging/comedi/drivers/jr3_pci.c index 25909a9..eb0a095 100644 --- a/drivers/staging/comedi/drivers/jr3_pci.c +++ b/drivers/staging/comedi/drivers/jr3_pci.c @@ -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); -- 2.7.4