Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1696178

[PATCH] alarmtimer: don't rate limit one-shot timers

From Greg Hackmann <ghackmann@google.com>
Newsgroups linux.kernel
Subject [PATCH] alarmtimer: don't rate limit one-shot timers
Date 2017-07-25 21:50 +0200
Message-ID <u7e0c-701-63@gated-at.bofh.it> (permalink)
References <u7crn-6ai-5@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


Commit ff86bf0c65f1 ("alarmtimer: Rate limit periodic intervals") sets a
minimum bound on the alarm timer interval.  This minimum bound shouldn't
be applied if the interval is 0.  Otherwise, one-shot timers will be
converted into periodic ones.

This patch is specific to 4.11.y and 4.12.y.  Older -stable trees have a
slightly different patch, and 4.13-rc2 isn't impacted due to a later
refactoring.

Fixes: ff86bf0c65f1 ("alarmtimer: Rate limit periodic intervals")
Reported-by: Ben Fennema <fennema@google.com>
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Cc: stable@vger.kernel.org
---
 kernel/time/alarmtimer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index ee2f4202d82a..11e70a38497c 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -665,7 +665,7 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
 	 * Rate limit to the tick as a hot fix to prevent DOS. Will be
 	 * mopped up later.
 	 */
-	if (timr->it.alarm.interval < TICK_NSEC)
+	if (timr->it.alarm.interval && timr->it.alarm.interval < TICK_NSEC)
 		timr->it.alarm.interval = TICK_NSEC;
 
 	exp = timespec64_to_ktime(new_setting->it_value);
-- 
2.14.0.rc0.284.gd933b75aa4-goog

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH] alarmtimer: don't rate limit one-shot timers Greg Hackmann <ghackmann@google.com> - 2017-07-24 19:30 +0200
  Re: [PATCH] alarmtimer: don't rate limit one-shot timers Greg KH <greg@kroah.com> - 2017-07-24 20:30 +0200
    Re: [PATCH] alarmtimer: don't rate limit one-shot timers Greg Hackmann <ghackmann@google.com> - 2017-07-24 23:50 +0200
      Re: [PATCH] alarmtimer: don't rate limit one-shot timers Greg KH <greg@kroah.com> - 2017-07-25 00:00 +0200
        Re: [PATCH] alarmtimer: don't rate limit one-shot timers Thomas Gleixner <tglx@linutronix.de> - 2017-07-25 09:10 +0200
          Re: [PATCH] alarmtimer: don't rate limit one-shot timers Greg KH <greg@kroah.com> - 2017-07-25 20:10 +0200
            [PATCH] alarmtimer: don't rate limit one-shot timers Greg Hackmann <ghackmann@google.com> - 2017-07-25 21:50 +0200
              Re: [PATCH] alarmtimer: don't rate limit one-shot timers Greg KH <greg@kroah.com> - 2017-07-25 23:50 +0200

csiph-web