From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Carpenter Date: Wed, 29 Oct 2014 08:42:50 +0000 Subject: [patch] hangcheck-timer: cleanup casting in hangcheck_init() Message-Id: <20141029084250.GA8939@mwanda> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Arnd Bergmann Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org The 32 bit addition "(hangcheck_margin + hangcheck_tick)" could potentially overflow. It triggers a static checker warning to have an overflowed addition followed by a no-op cast. I have moved the cast so that the addition can't overflow. Also I removed the unneeded cast on the following line since both "hangcheck_tsc_margin" and "TIMER_FREQ" are already 64 bit types. Signed-off-by: Dan Carpenter diff --git a/drivers/char/hangcheck-timer.c b/drivers/char/hangcheck-timer.c index ebc4c73..a7c5c59 100644 --- a/drivers/char/hangcheck-timer.c +++ b/drivers/char/hangcheck-timer.c @@ -168,8 +168,8 @@ static int __init hangcheck_init(void) printk("Hangcheck: starting hangcheck timer %s (tick is %d seconds, margin is %d seconds).\n", VERSION_STR, hangcheck_tick, hangcheck_margin); hangcheck_tsc_margin - (unsigned long long)(hangcheck_margin + hangcheck_tick); - hangcheck_tsc_margin *= (unsigned long long)TIMER_FREQ; + (unsigned long long)hangcheck_margin + hangcheck_tick; + hangcheck_tsc_margin *= TIMER_FREQ; hangcheck_tsc = ktime_get_ns(); mod_timer(&hangcheck_ticktock, jiffies + (hangcheck_tick*HZ));