From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:49794 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932973AbdERKy0 (ORCPT ); Thu, 18 May 2017 06:54:26 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ian Abbott Subject: [PATCH 4.10 15/93] staging: comedi: jr3_pci: cope with jiffies wraparound Date: Thu, 18 May 2017 12:46:44 +0200 Message-Id: <20170518104743.760688911@linuxfoundation.org> In-Reply-To: <20170518104743.163522815@linuxfoundation.org> References: <20170518104743.163522815@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ian Abbott commit 8ec04a491825e08068e92bed0bba7821893b6433 upstream. 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. 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(-) --- 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 lo 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);