Daniel Axtens c5ae366e12 sched/fair: WARN() and refuse to set buddy when !se->on_rq ...

If we set a next or last buddy for a se that is not on_rq, we will
end up taking a NULL pointer dereference in wakeup_preempt_entity
via pick_next_task_fair.

Detect when we would be about to do that, throw a warning and
then refuse to actually set it.

This has been suggested at least twice:

  https://marc.info/?l=linux-kernel&m=146651668921468&w=2
  https://lkml.org/lkml/2016/6/16/663

I recently had to debug a problem with these (we hadn't backported
Konstantin's patches in this area) and this would have saved a lot
of time/pain.

Just do it.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Cc: Ben Segall <bsegall@google.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170510201139.16236-1-dja@axtens.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2017-06-20 12:26:52 +02:00

..

bpf

net: Make IP alignment calulations clearer.

2017-05-22 12:27:07 -04:00

cgroup

Merge branch 'for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

2017-05-01 13:52:24 -07:00

configs

config: android-base: enable hardened usercopy and kernel ASLR

2017-02-27 18:43:46 -08:00

debug

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

events

perf/callchain: Force USER_DS when invoking perf_callchain_user()

2017-05-10 07:54:00 +02:00

gcov

gcov: support GCC 7.1

2017-05-12 15:57:15 -07:00

irq

Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-05-21 11:45:26 -07:00

livepatch

Merge branches 'for-4.12/upstream' and 'for-4.12/klp-hybrid-consistency-model' into for-linus

2017-05-01 21:49:28 +02:00

locking

Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-05-10 10:30:46 -07:00

power

Merge branches 'pm-sleep' and 'powercap'

2017-05-22 20:32:05 +02:00

printk

printk: Adjust system_state checks

2017-05-23 10:01:37 +02:00

rcu

Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-05-10 10:30:46 -07:00

sched

sched/fair: WARN() and refuse to set buddy when !se->on_rq

2017-06-20 12:26:52 +02:00

time

sched/clock: Remove unused argument to sched_clock_idle_wakeup_event()

2017-05-15 10:15:18 +02:00

trace

This fixes a bug caused by not cleaning up the new instance unique triggers

2017-05-20 23:39:03 -07:00

.gitignore

…

acct.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

async.c

async: Adjust system_state checks

2017-05-23 10:01:37 +02:00

audit_fsnotify.c

Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2017-05-03 11:05:15 -07:00

audit_tree.c

Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2017-05-03 11:05:15 -07:00

audit_watch.c

Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2017-05-03 11:05:15 -07:00

audit.c

Merge branch 'stable-4.12' of git://git.infradead.org/users/pcmoore/audit

2017-05-03 09:21:59 -07:00

audit.h

audit: Use timespec64 to represent audit timestamps

2017-05-02 10:16:05 -04:00

auditfilter.c

audit: kernel generated netlink traffic should have a portid of 0

2017-05-02 10:16:05 -04:00

auditsc.c

Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

2017-05-03 11:05:15 -07:00

backtracetest.c

…

bounds.c

…

capability.c

capability: export has_capability

2017-01-12 07:01:56 -07:00

compat.c

time: Change k_clock nsleep() to use timespec64

2017-04-14 21:49:56 +02:00

configs.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

context_tracking.c

…

cpu_pm.c

…

cpu.c

Merge branch 'linus' into locking/core, to pick up fixes

2017-04-14 10:29:40 +02:00

crash_core.c

ia64: reuse append_elf_note() and final_note() functions

2017-05-08 17:15:11 -07:00

crash_dump.c

…

cred.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/coredump.h>

2017-03-02 08:42:28 +01:00

delayacct.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

dma.c

…

elfcore.c

…

exec_domain.c

…

exit.c

userfaultfd: non-cooperative: rollback userfaultfd_exit

2017-03-09 17:01:09 -08:00

extable.c

extable: Adjust system_state checks

2017-05-23 10:01:37 +02:00

fork.c

pid_ns: Fix race between setns'ed fork() and zap_pid_ns_processes()

2017-05-13 17:26:02 -05:00

freezer.c

freezer, oom: check TIF_MEMDIE on the correct task

2016-07-28 16:07:41 -07:00

futex_compat.c

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

2016-12-24 11:46:01 -08:00

futex.c

futex: Clarify mark_wake_futex memory barrier usage

2017-04-15 16:03:46 +02:00

groups.c

mm, vmalloc: use __GFP_HIGHMEM implicitly

2017-05-08 17:15:13 -07:00

hung_task.c

kernel/hung_task.c: defer showing held locks

2017-05-08 17:15:10 -07:00

irq_work.c

…

jump_label.c

This release has no new tracing features, just clean ups, minor fixes

2017-02-27 13:26:17 -08:00

kallsyms.c

bpf: make jited programs visible in traces

2017-02-17 13:40:05 -05:00

kcmp.c

…

Kconfig.freezer

…

Kconfig.hz

…

Kconfig.locks

locking/mutex: Allow MUTEX_SPIN_ON_OWNER when DEBUG_MUTEXES

2016-10-25 11:31:51 +02:00

Kconfig.preempt

…

kcov.c

kcov: simplify interrupt check

2017-05-08 17:15:12 -07:00

kexec_core.c

ia64: reuse append_elf_note() and final_note() functions

2017-05-08 17:15:11 -07:00

kexec_file.c

kexec, x86/purgatory: Unbreak it and clean it up

2017-03-10 20:55:09 +01:00

kexec_internal.h

kexec, x86/purgatory: Unbreak it and clean it up

2017-03-10 20:55:09 +01:00

kexec.c

kexec: allow architectures to override boot mapping

2016-08-02 19:35:27 -04:00

kmod.c

sched/headers, vfs/execve: Prepare to move the do_execve*() prototypes from <linux/sched.h> to <linux/binfmts.h>

2017-03-02 08:42:39 +01:00

kprobes.c

kprobes: Document how optimized kprobes are removed from module unload

2017-05-17 21:55:58 -04:00

ksysfs.c

crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_CORE

2017-05-08 17:15:11 -07:00

kthread.c

cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups

2017-03-17 10:18:47 -04:00

latencytop.c

sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>

2017-03-02 08:42:39 +01:00

Makefile

crash: move crashkernel parsing and vmcore related code under CONFIG_CRASH_CORE

2017-05-08 17:15:11 -07:00

membarrier.c

Fix: Disable sys_membarrier when nohz_full is enabled

2017-01-23 11:32:16 -08:00

memremap.c

mm, zone_device: Replace {get, put}_zone_device_page() with a single reference to fix pmem crash

2017-05-01 09:15:53 +02:00

module_signing.c

…

module-internal.h

…

module.c

kernel/module.c: use set_memory.h header

2017-05-08 17:15:14 -07:00

notifier.c

kernel/notifier.c: simplify expression

2017-02-24 17:46:56 -08:00

nsproxy.c

perf: Add PERF_RECORD_NAMESPACES to include namespaces related info

2017-03-13 15:57:41 -03:00

padata.c

padata: get_next is never NULL

2017-04-21 20:30:46 +08:00

panic.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

params.c

boot/param: Move next_arg() function to lib/cmdline.c for later reuse

2017-04-18 10:37:13 +02:00

pid_namespace.c

pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes

2017-05-13 17:26:01 -05:00

pid.c

pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid()

2017-05-08 17:15:12 -07:00

profile.c

sched/headers: Prepare to move sched_info_on() and force_schedstat_enabled() from <linux/sched.h> to <linux/sched/stat.h>

2017-03-02 08:42:39 +01:00

ptrace.c

ptrace: fix PTRACE_LISTEN race corrupting task->state

2017-04-08 00:47:48 -07:00

range.c

…

reboot.c

…

relay.c

Merge branch 'work.splice' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2017-05-02 11:38:06 -07:00

resource.c

…

seccomp.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>

2017-03-02 08:42:36 +01:00

signal.c

Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-05-10 10:30:46 -07:00

smp.c

smp, cpumask: Use non-atomic cpumask_{set,clear}_cpu()

2017-05-23 10:01:32 +02:00

smpboot.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

smpboot.h

…

softirq.c

sched/core: Remove 'task' parameter and rename tsk_restore_flags() to current_restore_flags()

2017-04-11 09:06:32 +02:00

stacktrace.c

stacktrace/x86: add function for detecting reliable stack traces

2017-03-08 09:18:02 +01:00

stop_machine.c

locking/core, stop_machine: Yield the CPU during stop machine()

2016-11-16 10:15:09 +01:00

sys_ni.c

move aio compat to fs/aio.c

2016-12-22 22:58:37 -05:00

sys.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2017-05-05 11:08:43 -07:00

sysctl_binary.c

net: Remove NET_CORE_BUDGET_USECS from sysctl binary interface.

2017-04-21 15:59:52 -04:00

sysctl.c

proc/sysctl: fix the int overflow for jiffies conversion

2017-05-08 17:15:10 -07:00

task_work.c

task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works

2016-08-02 19:35:02 -04:00

taskstats.c

taskstats: add e/u/stime for TGID command

2017-05-08 17:15:12 -07:00

test_kprobes.c

…

torture.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/clock.h>

2017-03-02 08:42:27 +01:00

tracepoint.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>

2017-03-02 08:42:35 +01:00

tsacct.c

sched/headers: Prepare to move cputime functionality from <linux/sched.h> into <linux/sched/cputime.h>

2017-03-02 08:42:39 +01:00

ucount.c

ucount: Remove the atomicity from ucount->count

2017-03-06 15:26:37 -06:00

uid16.c

sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>

2017-03-02 08:42:31 +01:00

up.c

smp: Add function to execute a function synchronously on a CPU

2016-09-05 13:52:39 +02:00

user_namespace.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>

2017-03-02 08:42:29 +01:00

user-return-notifier.c

…

user.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/user.h>

2017-03-02 08:42:29 +01:00

utsname_sysctl.c

sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>

2017-03-03 01:45:36 +01:00

utsname.c

sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>

2017-03-02 08:42:38 +01:00

watchdog_hld.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

watchdog.c

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

2017-03-02 08:42:34 +01:00

workqueue_internal.h

…

workqueue.c

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-05-01 19:12:53 -07:00