patch "staging: comedi: jr3_pci: cope with jiffies wraparound" added to staging-next

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This is a note to let you know that I've just added the patch titled

    staging: comedi: jr3_pci: cope with jiffies wraparound

to my staging git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


>From 8ec04a491825e08068e92bed0bba7821893b6433 Mon Sep 17 00:00:00 2001
From: Ian Abbott <abbotti@xxxxxxxxx>
Date: Fri, 17 Feb 2017 11:09:09 +0000
Subject: 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: <stable@xxxxxxxxxxxxxxx> # 3.15+
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 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 25909a936e7c..eb0a095efe9c 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);
-- 
2.12.0





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