linux-toradex.git/kernel/time/alarmtimer.c, branch v5.3-rc6

alarmtimer: Fix kerneldoc comment for alarmtimer_suspend()

2019-06-14T15:04:04+00:00

This brings the kernel doc in line with the function signature.

Signed-off-by: Yangtao Li 
Signed-off-by: Thomas Gleixner 
Cc: john.stultz@linaro.org
Cc: sboyd@kernel.org
Link: https://lkml.kernel.org/r/20190525183925.18963-1-tiny.windzz@gmail.com

alarmtimer: Return correct remaining time

2019-04-10T13:23:26+00:00

To calculate a remaining time, it's required to subtract the current time
from the expiration time. In alarm_timer_remaining() the arguments of
ktime_sub are swapped.

Fixes: d653d8457c76 ("alarmtimer: Implement remaining callback")
Signed-off-by: Andrei Vagin 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Mukesh Ojha 
Cc: Stephen Boyd 
Cc: John Stultz 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190408041542.26338-1-avagin@gmail.com

time: Remove license boilerplate

2018-11-23T10:51:21+00:00

The SPDX identifier defines the license of the files already. No need for
the boilerplates.

Signed-off-by: Thomas Gleixner 
Acked-by: Kees Cook 
Acked-by: Ingo Molnar 
Acked-by: John Stultz 
Acked-by: Corey Minyard 
Acked-by: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Kate Stewart 
Cc: Philippe Ombredanne 
Cc: Peter Anvin 
Cc: Russell King 
Cc: Richard Cochran 
Cc: Nicolas Pitre 
Cc: David Riley 
Cc: Colin Cross 
Cc: Mark Brown 
Cc: Paul E. McKenney 
Link: https://lkml.kernel.org/r/20181031182253.132458951@linutronix.de

time: Add SPDX license identifiers

2018-11-23T10:51:20+00:00

Update the time(r) core files files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of the
full boiler plate text.

This work is based on a script and data from Philippe Ombredanne, Kate
Stewart and myself. The data has been created with two independent license
scanners and manual inspection.

The following files do not contain any direct license information and have
been omitted from the big initial SPDX changes:

  timeconst.bc: The .bc files were not touched
  time.c, timer.c, timekeeping.c: Licence was deduced from EXPORT_SYMBOL_GPL

As those files do not contain direct license references they fall under the
project license, i.e. GPL V2 only.

Signed-off-by: Thomas Gleixner 
Acked-by: Kees Cook 
Acked-by: Ingo Molnar 
Acked-by: John Stultz 
Acked-by: Corey Minyard 
Cc: Peter Zijlstra 
Cc: Kate Stewart 
Cc: Philippe Ombredanne 
Cc: Russell King 
Cc: Richard Cochran 
Cc: Nicolas Pitre 
Cc: David Riley 
Cc: Colin Cross 
Cc: Mark Brown 
Cc: H. Peter Anvin 
Cc: Paul E. McKenney 
Link: https://lkml.kernel.org/r/20181031182252.879109557@linutronix.de

alarmtimer: Prevent overflow for relative nanosleep

2018-07-02T09:33:26+00:00

Air Icy reported:

  UBSAN: Undefined behaviour in kernel/time/alarmtimer.c:811:7
  signed integer overflow:
  1529859276030040771 + 9223372036854775807 cannot be represented in type 'long long int'
  Call Trace:
   alarm_timer_nsleep+0x44c/0x510 kernel/time/alarmtimer.c:811
   __do_sys_clock_nanosleep kernel/time/posix-timers.c:1235 [inline]
   __se_sys_clock_nanosleep kernel/time/posix-timers.c:1213 [inline]
   __x64_sys_clock_nanosleep+0x326/0x4e0 kernel/time/posix-timers.c:1213
   do_syscall_64+0xb8/0x3a0 arch/x86/entry/common.c:290

alarm_timer_nsleep() uses ktime_add() to add the current time and the
relative expiry value. ktime_add() has no sanity checks so the addition
can overflow when the relative timeout is large enough.

Use ktime_add_safe() which has the necessary sanity checks in place and
limits the result to the valid range.

Fixes: 9a7adcf5c6de ("timers: Posix interface for alarm-timers")
Reported-by: Team OWL337 
Signed-off-by: Thomas Gleixner 
Cc: John Stultz 
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1807020926360.1595@nanos.tec.linutronix.de

posix-timers: Make forward callback return s64

2018-07-02T09:33:25+00:00

The posix timer ti_overrun handling is broken because the forwarding
functions can return a huge number of overruns which does not fit in an
int. As a consequence timer_getoverrun(2) and siginfo::si_overrun can turn
into random number generators.

As a first step to address that let the timer_forward() callbacks return
the full 64 bit value.

Cast it to (int) temporarily until k_itimer::ti_overrun is converted to
64bit and the conversion to user space visible values is sanitized.

Reported-by: Team OWL337 
Signed-off-by: Thomas Gleixner 
Acked-by: John Stultz 
Cc: Peter Zijlstra 
Cc: Michael Kerrisk 
Link: https://lkml.kernel.org/r/20180626132704.922098090@linutronix.de

alarmtimer: Init nanosleep alarm timer on stack

2018-03-29T14:10:07+00:00

syszbot reported the following debugobjects splat:

 ODEBUG: object is on stack, but not annotated
 WARNING: CPU: 0 PID: 4185 at lib/debugobjects.c:328

 RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:327 [inline]
 debug_object_init+0x17/0x20 lib/debugobjects.c:391
 debug_hrtimer_init kernel/time/hrtimer.c:410 [inline]
 debug_init kernel/time/hrtimer.c:458 [inline]
 hrtimer_init+0x8c/0x410 kernel/time/hrtimer.c:1259
 alarm_init kernel/time/alarmtimer.c:339 [inline]
 alarm_timer_nsleep+0x164/0x4d0 kernel/time/alarmtimer.c:787
 SYSC_clock_nanosleep kernel/time/posix-timers.c:1226 [inline]
 SyS_clock_nanosleep+0x235/0x330 kernel/time/posix-timers.c:1204
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

This happens because the hrtimer for the alarm nanosleep is on stack, but
the code does not use the proper debug objects initialization.

Split out the code for the allocated use cases and invoke
hrtimer_init_on_stack() for the nanosleep related functions.

Reported-by: syzbot+a3e0726462b2e346a31d@syzkaller.appspotmail.com
Signed-off-by: Thomas Gleixner 
Cc: John Stultz 
Cc: syzkaller-bugs@googlegroups.com
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1803261528270.1585@nanos.tec.linutronix.de

alarmtimer: Ensure RTC module is not unloaded

2017-08-31T19:36:45+00:00

When registering the rtc device to be used to handle alarm timers,
get_device is used to ensure the device doesn't go away but the module can
still be unloaded.

Call try_module_get to ensure the rtc driver will not go away.

Reported-and-tested-by: Michal Simek 
Signed-off-by: Alexandre Belloni 
Signed-off-by: Thomas Gleixner 
Acked-by: John Stultz 
Cc: Stephen Boyd 
Link: http://lkml.kernel.org/r/20170820220146.30969-1-alexandre.belloni@free-electrons.com

alarmtimer: Fix unavailable wake-up source in sysfs

2017-08-17T19:15:10+00:00

Currently the alarmtimer registers a wake-up source unconditionally,
regardless of the system having a (wake-up capable) RTC or not.
Hence the alarmtimer will always show up in
/sys/kernel/debug/wakeup_sources, even if it is not available, and thus
cannot be a wake-up source.

To fix this, postpone registration until a wake-up capable RTC device is
added.

Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Miroslav Lichvar 
Cc: Richard Cochran 
Cc: Prarit Bhargava 
Cc: Stephen Boyd 
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: John Stultz

nanosleep: Use get_timespec64() and put_timespec64()

2017-06-30T08:14:14+00:00

Usage of these apis and their compat versions makes
the syscalls: clock_nanosleep and nanosleep and
their compat implementations simpler.

This is a preparatory patch to isolate data conversions to
struct timespec64 at userspace boundaries. This helps contain
the changes needed to transition to new y2038 safe types.

Signed-off-by: Deepa Dinamani 
Signed-off-by: Al Viro