linux-toradex.git/kernel/hrtimer.c, branch v2.6.23.12

hrtimers: avoid overflow for large relative timeouts (CVE-2007-5966)

2007-12-14T17:50:55+00:00

patch 62f0f61e6673e67151a7c8c0f9a09c7ea43fe2b5 in mainline

Relative hrtimers with a large timeout value might end up as negative
timer values, when the current time is added in hrtimer_start().

This in turn is causing the clockevents_set_next() function to set an
huge timeout and sleep for quite a long time when we have a clock
source which is capable of long sleeps like HPET. With PIT this almost
goes unnoticed as the maximum delta is ~27ms. The non-hrt/nohz code
sorts this out in the next timer interrupt, so we never noticed that
problem which has been there since the first day of hrtimers.

This bug became more apparent in 2.6.24 which activates HPET on more
hardware.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

Cache xtime every call to update_wall_time

2007-07-25T17:17:44+00:00

This avoids xtime lag seen with dynticks, because while 'xtime' itself
is still not updated often, we keep a 'xtime_cache' variable around that
contains the approximate real-time that _is_ updated each time we do a
'update_wall_time()', and is thus never off by more than one tick.

IOW, this restores the original semantics for 'xtime' users, as long as
you use the proper abstraction functions (ie 'current_kernel_time()' or
'get_seconds()' depending on whether you want a timespec or just the
seconds field).

[ Updated Patch.  As penance for my sins I've also yanked another #ifdef
  that was added to avoid the xtime lag w/ hrtimers.  ]

Signed-off-by: John Stultz 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Signed-off-by: Linus Torvalds

Cleanup non-arch xtime uses, use get_seconds() or current_kernel_time().

2007-07-25T17:09:20+00:00

This avoids use of the kernel-internal "xtime" variable directly outside
of the actual time-related functions.  Instead, use the helper functions
that we already have available to us.

This doesn't actually change any behaviour, but this will allow us to
fix the fact that "xtime" isn't updated very often with CONFIG_NO_HZ
(because much of the realtime information is maintained as separate
offsets to 'xtime'), which has caused interfaces that use xtime directly
to get a time that is out of sync with the real-time clock by up to a
third of a second or so.

Signed-off-by: John Stultz 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Signed-off-by: Linus Torvalds

hrtimer: speedup hrtimer_enqueue

2007-07-22T00:49:15+00:00

Speedup hrtimer_enqueue by evaluating the rbtree insertion result.

Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner 
Cc: john stultz 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

highres: improve debug output

2007-07-22T00:49:15+00:00

Add some more debug information to the hrtimer and clock events code.

Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner 
Cc: john stultz 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[HRTIMER] Fix cpu pointer arg to clockevents_notify()

2007-07-17T00:29:56+00:00

All of the clockevent notifiers expect a pointer to
an "unsigned int" cpu argument, but hrtimer_cpu_notify()
passes in a pointer to a long.

[ Discussed with and ok by Thomas Gleixner ]

Signed-off-by: David S. Miller 
Signed-off-by: Linus Torvalds

Add suspend-related notifications for CPU hotplug

2007-05-09T19:30:56+00:00

Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki 
Cc: Gautham R Shenoy 
Cc: Pavel Machek 
Signed-off-by: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

export hrtimer_forward

2007-05-08T18:15:15+00:00

Other symbols of the hrtimers API are already exported.

Signed-off-by: Stas Sergeev 
Acked-by: Thomas Gleixner 
Cc: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[NET]: Fix networking compilation errors

2007-04-27T22:31:24+00:00

Fix miscellaneous networking compilation errors.

 (*) Export ktime_add_ns() for modules.

 (*) wext_proc_init() should have an ANSI declaration.

Signed-off-by: David Howells 
Signed-off-by: David S. Miller

[NET_SCHED]: Use ktime as clocksource

2007-04-26T05:26:04+00:00

Get rid of the manual clock source selection mess and use ktime. Also
use a scalar representation, which allows to clean up pkt_sched.h a bit
more and results in less ktime_to_ns() calls in most cases.

The PSCHED_US2JIFFIE/PSCHED_JIFFIE2US macros are implemented quite
inefficient by this patch, following patches will convert all qdiscs
to hrtimers and get rid of them entirely.

Signed-off-by: Patrick McHardy 
Signed-off-by: David S. Miller