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* posix-timers: Move compat_timer_create() to native, get rid of set_fs()Al Viro2017-06-143-36/+42
| | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-14-viro@ZenIV.linux.org.uk
* posix-timers: Move compat versions of clock_gettime/settime/getresAl Viro2017-06-143-55/+115
| | | | | | | | | | | Move them to the native implementations and get rid of the set_fs() hackery. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-13-viro@ZenIV.linux.org.uk
* itimers: Move compat itimer syscalls to native onesAl Viro2017-06-143-53/+56
| | | | | | | | | | | get rid of set_fs(), sanitize compat copyin/copyout. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-12-viro@ZenIV.linux.org.uk
* posix-timers: Take compat timer_gettime(2) to native oneAl Viro2017-06-143-26/+35
| | | | | | | | | | | ... and get rid of set_fs() in there Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-11-viro@ZenIV.linux.org.uk
* posix-timers: Take compat timer_settime(2) to native oneAl Viro2017-06-143-47/+64
| | | | | | | | | | | ... and get rid of set_fs() in there Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-10-viro@ZenIV.linux.org.uk
* ntp: Move adjtimex related compat syscalls to native counterpartsAl Viro2017-06-144-90/+104
| | | | | | | | | | | | Get rid of set_fs() mess and sanitize compat_{get,put}_timex(), while we are at it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-9-viro@ZenIV.linux.org.uk
* posix-timers: Kill ->nsleep_restart()Al Viro2017-06-144-12/+1
| | | | | | | | | | | No more users. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-8-viro@ZenIV.linux.org.uk
* hrtimers/posix-timers: Merge nanosleep timespec copyout logics into a new helperAl Viro2017-06-143-29/+23
| | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-7-viro@ZenIV.linux.org.uk
* time/posix-timers: Move the compat copyouts to the nanosleep implementationsAl Viro2017-06-146-167/+129
| | | | | | | | | | | | | | | | | Turn restart_block.nanosleep.{rmtp,compat_rmtp} into a tagged union (kind = 1 -> native, kind = 2 -> compat, kind = 0 -> nothing) and make the places doing actual copyout handle compat as well as native (that will become a helper in the next commit). Result: compat wrappers, messing with reassignments, etc. are gone. [ tglx: Folded in a variant of Peter Zijlstras enum patch ] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-6-viro@ZenIV.linux.org.uk
* posix-timers: Store rmtp into restart_block in sys_clock_nanosleep()Al Viro2017-06-144-22/+10
| | | | | | | | | | | ... instead of doing that in every ->nsleep() instance Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-5-viro@ZenIV.linux.org.uk
* hrtimer: Move copyout of remaining time to do_nanosleep()Al Viro2017-06-141-42/+20
| | | | | | | | | | | | | | | | | | | The hrtimer nanosleep() implementation can be simplified by moving the copy out of the remaining time to do_nanosleep() which is shared between the real nanosleep function and the restart function. The pointer to the timespec64 which is updated is already stored in the restart block at the call site, so the seperate handling of nanosleep and restart function can be avoided. [ tglx: Added changelog ] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-4-viro@ZenIV.linux.org.uk
* hrtimer_nanosleep(): Pass rmtp in restart_blockAl Viro2017-06-144-10/+17
| | | | | | | | | | | | | | Store the pointer to the timespec which gets updated with the remaining time in the restart block and remove the function argument. [ tglx: Added changelog ] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-3-viro@ZenIV.linux.org.uk
* alarmtimer: Move copyout and freeze handling into alarmtimer_do_nsleep()Al Viro2017-06-141-70/+32
| | | | | | | | | | | | | | | | | | | | The alarmtimer nanosleep() implementation can be simplified by moving the copy out of the remaining time to alarmtimer_do_nsleep() which is shared between the real nanosleep function and the restart function. The pointer to the timespec64 which is updated has to be stored in the restart block anyway. Instead of storing it only in the restart case, store it before calling alarmtimer_do_nsleep() and copy the remaining time in the signal exit path. [ tglx: Added changelog ] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-2-viro@ZenIV.linux.org.uk
* posix-cpu-timers: Move copyout of timespec into do_cpu_nanosleep()Al Viro2017-06-141-35/+28
| | | | | | | | | | | | | | | | | | | | The posix-cpu-timer nanosleep() implementation can be simplified by moving the copy out of the remaining time to do_cpu_nanosleep() which is shared between the real nanosleep function and the restart function. The pointer to the timespec64 which is updated has to be stored in the restart block anyway. Instead of storing it only in the restart case, store it before calling do_cpu_nanosleep() and copy the remaining time in the signal exit path. [ tglx: Added changelog ] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170607084241.28657-1-viro@ZenIV.linux.org.uk
* posix-timers: Handle relative posix-timers correctlyThomas Gleixner2017-06-121-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The recent rework of the posix timer internals broke the magic posix mechanism, which requires that relative timers are not affected by modifications of the underlying clock. That means relative CLOCK_REALTIME timers cannot use CLOCK_REALTIME, because that can be set and adjusted. The underlying hrtimer switches the clock for these timers to CLOCK_MONOTONIC. That still works, but reading the remaining time of such a timer has been broken in the rework. The old code used the hrtimer internals directly and avoided the posix clock callbacks. Now common_timer_get() uses the underlying kclock->timer_get() callback, which is still CLOCK_REALTIME based. So the remaining time of such a timer is calculated against the wrong time base. Handle it by switching the k_itimer->kclock pointer according to the resulting hrtimer mode. k_itimer->it_clock still contains CLOCK_REALTIME because the timer might be set with ABSTIME later and then it needs to switch back to the realtime posix clock implementation. Fixes: eae1c4ae275f ("posix-timers: Make use of cancel/arm callbacks") Reported-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Link: http://lkml.kernel.org/r/20170609201156.GB21491@outlook.office365.com
* posix-timers: Zero out oldval itimerspecThomas Gleixner2017-06-121-0/+2
| | | | | | | | | | | | | | | | | The recent posix timer rework moved the clearing of the itimerspec to the real syscall implementation, but forgot that the kclock->timer_get() is used by timer_settime() as well. That results in an uninitialized variable and bogus values returned to user space. Add the missing memset to timer_settime(). Fixes: eabdec043853 ("posix-timers: Zero settings value in common code") Reported-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Link: http://lkml.kernel.org/r/20170609201156.GB21491@outlook.office365.com
* posix-timers: Fix inverted SIGEV_NONE logic in common_timer_get()Thomas Gleixner2017-06-121-1/+1
| | | | | | | | | | | | | | | | | The refactoring of the posix-timer core to allow better code sharing introduced inverted logic vs. SIGEV_NONE timers in common_timer_get(). That causes hrtimer_forward() to be called on active timers, which rightfully triggers the warning hrtimer_forward(). Make sig_none what it says: signal mode == SIGEV_NONE. Fixes: 91d57bae0868 ("posix-timers: Make use of forward/remaining callbacks") Reported-by: Ye Xiaolong <xiaolong.ye@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170609104457.GA39907@inn.lkp.intel.com
* alarmtimer: Switch over to generic set/get/rearm routineThomas Gleixner2017-06-043-110/+29
| | | | | | | | | | | | All required callbacks are in place. Switch the alarm timer based posix interval timer callbacks to the common implementation and remove the incorrect private implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.825471962@linutronix.de
* alarmtimer: Implement arm callbackThomas Gleixner2017-06-041-0/+22
| | | | | | | | | | Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.747567162@linutronix.de
* alarmtimer: Implement try_to_cancel callbackThomas Gleixner2017-06-041-0/+10
| | | | | | | | | | Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.670026824@linutronix.de
* alarmtimer: Implement remaining callbackThomas Gleixner2017-06-041-9/+22
| | | | | | | | | | Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.592676753@linutronix.de
* alarmtimer: Implement forward callbackThomas Gleixner2017-06-041-0/+13
| | | | | | | | | | Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.513694229@linutronix.de
* alarmtimer: Implement timer_rearm() callbackThomas Gleixner2017-06-041-1/+14
| | | | | | | | | | Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.434598989@linutronix.de
* posix-timers: Make use of cancel/arm callbacksThomas Gleixner2017-06-041-81/+100
| | | | | | | | | | | | Replace the hrtimer calls by calls to the new try_to_cancel()/arm() kclock callbacks and move the hrtimer specific implementation into the corresponding callback functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.355396667@linutronix.de
* posix-timers: Add cancel/arm callbacksThomas Gleixner2017-06-041-0/+3
| | | | | | | | | | | | Add timer_try_to_cancel() and timer_arm() callbacks to kclock which allow to make common_timer_set() usable by both hrtimer and alarmtimer based clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.278022962@linutronix.de
* posix-timers: Zero settings value in common codeThomas Gleixner2017-06-042-6/+2
| | | | | | | | | | | Zero out the settings struct in the common code so the callbacks do not have to do it themself. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.200870713@linutronix.de
* posix-timers: Make use of forward/remaining callbacksThomas Gleixner2017-06-041-15/+49
| | | | | | | | | | | | Replace the hrtimer calls by calls to the new forward/remaining kclock callbacks and move the hrtimer specific implementation into the corresponding callback functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.121437232@linutronix.de
* posix-timers: Add forward/remaining callbacksThomas Gleixner2017-06-041-0/+2
| | | | | | | | | | | Add two callbacks to kclock which allow using common_)timer_get() for both hrtimer and alarm timer based clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.044915536@linutronix.de
* posix-timers: Add active flag to k_itimerThomas Gleixner2017-06-041-1/+7
| | | | | | | | | | | | Keep track of the activation state of posix timers. This is a preparatory change for making common_timer_get() usable by both hrtimer and alarm timer implementations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.967783982@linutronix.de
* posix-timers: Use timer_rearm() callback in posixtimer_rearm()Thomas Gleixner2017-06-043-10/+11
| | | | | | | | | | | | | Use the new timer_rearm() callback to replace the conditional hardcoded calls into the hrtimer and cpu timer code. This allows later to bring the same logic to alarmtimers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.889661919@linutronix.de
* posix-timers: Rename do_schedule_next_timerThomas Gleixner2017-06-043-7/+7
| | | | | | | | | | | That function is a misnomer. Rename it with a proper prefix to posixtimer_rearm(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.811362578@linutronix.de
* posix-timers: Add timer_rearm() callbackThomas Gleixner2017-06-041-15/+18
| | | | | | | | | | | Add a timer_rearm() callback which is used to make the rescheduling of posix interval timers independent of the underlying clock implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.732632167@linutronix.de
* posix-timers: Store k_clock pointer in k_itimerThomas Gleixner2017-06-042-3/+6
| | | | | | | | | | | | Having the k_clock pointer in the k_itimer struct avoids the lookup in several code pathes and makes the next steps of unification of the hrtimer and alarmtimer based posix timers simpler. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.641222072@linutronix.de
* posix-timers: Move interval out of the unionThomas Gleixner2017-06-042-17/+16
| | | | | | | | | | | | | | Preparatory patch to unify the alarm timer and hrtimer based posix interval timer handling. The interval is used as a criteria for rearming decisions so moving it out of the clock specific data structures allows later unification. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.563922908@linutronix.de
* posix-timers: Unify overrun/requeue_pending handlingThomas Gleixner2017-06-042-18/+15
| | | | | | | | | | | | | hrtimer based posix-timers and posix-cpu-timers handle the update of the rearming and overflow related status fields differently. Move that update to the common rearming code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.484936964@linutronix.de
* posix-timers: Move posix-timer internals to coreThomas Gleixner2017-06-045-0/+36
| | | | | | | | | | | | None of these declarations is required outside of kernel/time. Move them to an internal header. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170530211656.394803853@linutronix.de
* posix-timers: Avoid gazillions of forward declarationsThomas Gleixner2017-06-041-101/+89
| | | | | | | | | | | Move it below the actual implementations as there are new callbacks coming which would require even more forward declarations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.238209952@linutronix.de
* posix-clocks: Remove interval timer facility and mmap/fasync callbacksThomas Gleixner2017-06-041-113/+0
| | | | | | | | | | | | | | | | | | | The only user of this facility is ptp_clock, which does not implement any of those functions. Remove them to prevent accidental users. Especially the interval timer interfaces are now more or less impossible to implement because the necessary infrastructure has been confined to the core code. Aside of that it's really complex to make these callbacks implemented according to spec as the alarm timer implementation demonstrates. If at all then a nanosleep callback might be a reasonable extension. For now keep just what ptp_clock needs. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.145036286@linutronix.de
* posix-timers: Remove unused export of posix_timer_event()Thomas Gleixner2017-06-041-1/+0
| | | | | | | | | | Since the removal of the mmtimer driver the export is not longer needed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.052744418@linutronix.de
* alarmtimer: Remove pointless config conditionalThomas Gleixner2017-06-041-2/+1
| | | | | | | | | | | Having a IF_ENABLED(CONFIG_POSIX_TIMERS) inside of a #ifdef CONFIG_POSIX_TIMERS section is pointless. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211655.975218056@linutronix.de
* Merge branch 'timers/urgent' into WIP.timersThomas Gleixner2017-06-0414-70/+114
|\ | | | | | | Pick up urgent fixes to avoid conflicts.
| * alarmtimer: Rate limit periodic intervalsThomas Gleixner2017-06-041-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The alarmtimer code has another source of potentially rearming itself too fast. Interval timers with a very samll interval have a similar CPU hog effect as the previously fixed overflow issue. The reason is that alarmtimers do not implement the normal protection against this kind of problem which the other posix timer use: timer expires -> queue signal -> deliver signal -> rearm timer This scheme brings the rearming under scheduler control and prevents permanently firing timers which hog the CPU. Bringing this scheme to the alarm timer code is a major overhaul because it lacks all the necessary mechanisms completely. So for a quick fix limit the interval to one jiffie. This is not problematic in practice as alarmtimers are usually backed by an RTC for suspend which have 1 second resolution. It could be therefor argued that the resolution of this clock should be set to 1 second in general, but that's outside the scope of this fix. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kostya Serebryany <kcc@google.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170530211655.896767100@linutronix.de
| * alarmtimer: Prevent overflow of relative timersThomas Gleixner2017-06-041-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andrey reported a alartimer related RCU stall while fuzzing the kernel with syzkaller. The reason for this is an overflow in ktime_add() which brings the resulting time into negative space and causes immediate expiry of the timer. The following rearm with a small interval does not bring the timer back into positive space due to the same issue. This results in a permanent firing alarmtimer which hogs the CPU. Use ktime_add_safe() instead which detects the overflow and clamps the result to KTIME_SEC_MAX. Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kostya Serebryany <kcc@google.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170530211655.802921648@linutronix.de
| * Merge branch 'for-linus' of ↵Linus Torvalds2017-06-021-0/+1
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull livepatching fix from Jiri Kosina: "Kconfig dependency fix for livepatching infrastructure from Miroslav Benes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: Make livepatch dependent on !TRIM_UNUSED_KSYMS
| | * livepatch: Make livepatch dependent on !TRIM_UNUSED_KSYMSMiroslav Benes2017-05-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If TRIM_UNUSED_KSYMS is enabled, all unneeded exported symbols are made unexported. Two-pass build of the kernel is done to find out which symbols are needed based on a configuration. This effectively complicates things for out-of-tree modules. Livepatch exports functions to (un)register and enable/disable a live patch. The only in-tree module which uses these functions is a sample in samples/livepatch/. If the sample is disabled, the functions are trimmed and out-of-tree live patches cannot be built. Note that live patches are intended to be built out-of-tree. Suggested-by: Michal Marek <mmarek@suse.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Jessica Yu <jeyu@redhat.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| * | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-05-271-8/+16
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixlet from Thomas Gleixner: "Silence dmesg spam by making the posix cpu timer printks depend on print_fatal_signals" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: posix-timers: Make signal printks conditional
| | * | posix-timers: Make signal printks conditionalThomas Gleixner2017-05-231-8/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A recent commit added extra printks for CPU/RT limits. This can result in excessive spam in dmesg. Make the printks conditional on print_fatal_signals. Fixes: e7ea7c9806a2 ("rlimits: Print more information when CPU/RT limits are exceeded") Reported-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arun Raghavan <arun@arunraghavan.net>
| * | | Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds2017-05-271-6/+18
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fix from Thomas Gleixner: "A fix for a state leak which was introduced in the recent rework of futex/rtmutex interaction" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock()
| | * | | futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock()Peter Zijlstra2017-05-221-6/+18
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Markus reported that the glibc/nptl/tst-robustpi8 test was failing after commit: cfafcd117da0 ("futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock()") The following trace shows the problem: ld-linux-x86-64-2161 [019] .... 410.760971: SyS_futex: 00007ffbeb76b028: 80000875 op=FUTEX_LOCK_PI ld-linux-x86-64-2161 [019] ...1 410.760972: lock_pi_update_atomic: 00007ffbeb76b028: curval=80000875 uval=80000875 newval=80000875 ret=0 ld-linux-x86-64-2165 [011] .... 410.760978: SyS_futex: 00007ffbeb76b028: 80000875 op=FUTEX_UNLOCK_PI ld-linux-x86-64-2165 [011] d..1 410.760979: do_futex: 00007ffbeb76b028: curval=80000875 uval=80000875 newval=80000871 ret=0 ld-linux-x86-64-2165 [011] .... 410.760980: SyS_futex: 00007ffbeb76b028: 80000871 ret=0000 ld-linux-x86-64-2161 [019] .... 410.760980: SyS_futex: 00007ffbeb76b028: 80000871 ret=ETIMEDOUT Task 2165 does an UNLOCK_PI, assigning the lock to the waiter task 2161 which then returns with -ETIMEDOUT. That wrecks the lock state, because now the owner isn't aware it acquired the lock and removes the pending robust list entry. If 2161 is killed, the robust list will not clear out this futex and the subsequent acquire on this futex will then (correctly) result in -ESRCH which is unexpected by glibc, triggers an internal assertion and dies. Task 2161 Task 2165 rt_mutex_wait_proxy_lock() timeout(); /* T2161 is still queued in the waiter list */ return -ETIMEDOUT; futex_unlock_pi() spin_lock(hb->lock); rtmutex_unlock() remove_rtmutex_waiter(T2161); mark_lock_available(); /* Make the next waiter owner of the user space side */ futex_uval = 2161; spin_unlock(hb->lock); spin_lock(hb->lock); rt_mutex_cleanup_proxy_lock() if (rtmutex_owner() !== current) ... return FAIL; .... return -ETIMEOUT; This means that rt_mutex_cleanup_proxy_lock() needs to call try_to_take_rt_mutex() so it can take over the rtmutex correctly which was assigned by the waker. If the rtmutex is owned by some other task then this call is harmless and just confirmes that the waiter is not able to acquire it. While there, fix what looks like a merge error which resulted in rt_mutex_cleanup_proxy_lock() having two calls to fixup_rt_mutex_waiters() and rt_mutex_wait_proxy_lock() not having any. Both should have one, since both potentially touch the waiter list. Fixes: 38d589f2fd08 ("futex,rt_mutex: Restructure rt_mutex_finish_proxy_lock()") Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Bug-Spotted-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Markus Trippelsdorf <markus@trippelsdorf.de> Link: http://lkml.kernel.org/r/20170519154850.mlomgdsd26drq5j6@hirez.programming.kicks-ass.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2017-05-271-5/+12
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull kthread fix from Thomas Gleixner: "A single fix which prevents a use after free when kthread fork fails" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kthread: Fix use-after-free if kthread fork fails
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