Patch "posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper" has been added to the 4.4-stable tree

Patch "posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper" has been added to the 4.4-stable tree

[gregkh]

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

    posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     posix-timers-handle-relative-timers-with-config_time_low_res-proper.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 572c39172684c3711e4a03c9a7380067e2b0661c Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 14 Jan 2016 16:54:47 +0000
Subject: posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper

From: Thomas Gleixner <tglx@linutronix.de>

commit 572c39172684c3711e4a03c9a7380067e2b0661c upstream.

As Helge reported for timerfd we have the same issue in posix timers. We
return remaining time larger than the programmed relative time to user space
in case of CONFIG_TIME_LOW_RES=y. Use the proper function to adjust the extra
time added in hrtimer_start_range_ns().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Helge Deller <deller@gmx.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: linux-m68k@lists.linux-m68k.org
Cc: dhowells@redhat.com
Link: http://lkml.kernel.org/r/20160114164159.450510905@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 kernel/time/posix-timers.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -760,7 +760,7 @@ common_timer_get(struct k_itimer *timr,
 	    (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
 		timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
 
-	remaining = ktime_sub(hrtimer_get_expires(timer), now);
+	remaining = __hrtimer_expires_remaining_adjusted(timer, now);
 	/* Return 0 only, when the timer is expired and not pending */
 	if (remaining.tv64 <= 0) {
 		/*


Patches currently in stable-queue which might be from tglx@linutronix.de are

queue-4.4/itimers-handle-relative-timers-with-config_time_low_res-proper.patch
queue-4.4/futex-drop-refcount-if-requeue_pi-acquired-the-rtmutex.patch
queue-4.4/x86-mm-pat-avoid-truncation-when-converting-cpa-numpages-to-address.patch
queue-4.4/x86-uaccess-64-handle-the-caching-of-4-byte-nocache-copies-properly-in-__copy_user_nocache.patch
queue-4.4/timerfd-handle-relative-timers-with-config_time_low_res-proper.patch
queue-4.4/posix-timers-handle-relative-timers-with-config_time_low_res-proper.patch
queue-4.4/x86-mm-fix-vmalloc_fault-to-handle-large-pages-properly.patch
queue-4.4/x86-mm-fix-types-used-in-pgprot-cacheability-flags-translations.patch
queue-4.4/x86-uaccess-64-make-the-__copy_user_nocache-assembly-code-more-readable.patch