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

    clockevents: Don't allow dummy broadcast timers

to the 3.0-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:
     clockevents-don-t-allow-dummy-broadcast-timers.patch
and it can be found in the queue-3.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From a7dc19b8652c862d5b7c4d2339bd3c428bd29c4a Mon Sep 17 00:00:00 2001
From: Mark Rutland <[email protected]>
Date: Thu, 7 Mar 2013 15:09:24 +0000
Subject: clockevents: Don't allow dummy broadcast timers

From: Mark Rutland <[email protected]>

commit a7dc19b8652c862d5b7c4d2339bd3c428bd29c4a upstream.

Currently tick_check_broadcast_device doesn't reject clock_event_devices
with CLOCK_EVT_FEAT_DUMMY, and may select them in preference to real
hardware if they have a higher rating value. In this situation, the
dummy timer is responsible for broadcasting to itself, and the core
clockevents code may attempt to call non-existent callbacks for
programming the dummy, eventually leading to a panic.

This patch makes tick_check_broadcast_device always reject dummy timers,
preventing this problem.

Signed-off-by: Mark Rutland <[email protected]>
Cc: [email protected]
Cc: Jon Medhurst (Tixy) <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 kernel/time/tick-broadcast.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -66,7 +66,8 @@ static void tick_broadcast_start_periodi
  */
 int tick_check_broadcast_device(struct clock_event_device *dev)
 {
-       if ((tick_broadcast_device.evtdev &&
+       if ((dev->features & CLOCK_EVT_FEAT_DUMMY) ||
+           (tick_broadcast_device.evtdev &&
             tick_broadcast_device.evtdev->rating >= dev->rating) ||
             (dev->features & CLOCK_EVT_FEAT_C3STOP))
                return 0;


Patches currently in stable-queue which might be from [email protected] are

queue-3.0/clockevents-don-t-allow-dummy-broadcast-timers.patch
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