Ulrich Obergfell ee89e71eb0 kernel/watchdog.c: avoid race between lockup detector suspend/resume and CPU hotplug ...

The lockup detector suspend/resume interface that was introduced by
commit 8c073d27d7ad ("watchdog: introduce watchdog_suspend() and
watchdog_resume()") does not protect itself against races with CPU
hotplug.  Hence, theoretically it is possible that a new watchdog thread
is started on a hotplugged CPU while the lockup detector is suspended,
and the thread could thus interfere unexpectedly with the code that
requested to suspend the lockup detector.

Avoid the race by calling

  get_online_cpus() in lockup_detector_suspend()
  put_online_cpus() in lockup_detector_resume()

Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2015-11-05 19:34:48 -08:00

..

bpf

bpf, verifier: annotate verbose printer with __printf

2015-11-03 11:29:56 -05:00

configs

kconfig: add xenconfig defconfig helper

2015-06-16 11:04:29 +01:00

debug

debug: prevent entering debug mode on panic/exception.

2015-02-19 12:39:03 -06:00

events

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2015-11-04 09:41:05 -08:00

gcov

gcov: add support for GCC 5.1

2015-06-30 19:44:57 -07:00

irq

Power management and ACPI updates for v4.4-rc1

2015-11-04 18:10:13 -08:00

livepatch

livepatch: Improve error handling in klp_disable_func()

2015-07-14 22:48:06 +02:00

locking

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

2015-11-03 18:03:50 -08:00

power

PM / hibernate: fix a comment typo

2015-10-14 02:37:17 +02:00

printk

kexec: split kexec_load syscall from kexec core code

2015-09-10 13:29:01 -07:00

rcu

Merge branches 'doc.2015.10.06a', 'percpu-rwsem.2015.10.06a' and 'torture.2015.10.06a' into HEAD

2015-10-07 16:06:25 -07:00

sched

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

2015-11-03 18:03:50 -08:00

time

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

2015-11-03 14:13:41 -08:00

trace

Merge branch 'for-4.4/core' of git://git.kernel.dk/linux-block

2015-11-04 20:28:10 -08:00

.gitignore

…

acct.c

acct: check FMODE_CAN_WRITE

2015-04-11 22:27:55 -04:00

async.c

kernel/async.c: switch to pr_foo()

2014-10-09 22:26:04 -04:00

audit_fsnotify.c

audit: clean simple fsnotify implementation

2015-08-06 16:14:53 -04:00

audit_tree.c

Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit

2015-09-08 13:34:59 -07:00

audit_watch.c

Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit

2015-09-08 13:34:59 -07:00

audit.c

Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit

2015-09-08 13:34:59 -07:00

audit.h

Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit

2015-09-08 13:34:59 -07:00

auditfilter.c

audit: implement audit by executable

2015-08-06 16:17:25 -04:00

auditsc.c

Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit

2015-09-08 13:34:59 -07:00

backtracetest.c

kernel/backtracetest.c: replace no level printk by pr_info()

2014-06-04 16:54:14 -07:00

bounds.c

page-cgroup: get rid of NR_PCG_FLAGS

2014-08-08 15:57:18 -07:00

capability.c

kernel: conditionally support non-root users, groups and capabilities

2015-04-15 16:35:22 -07:00

cgroup_freezer.c

cgroup: allow a cgroup subsystem to reject a fork

2015-07-14 17:29:23 -04:00

cgroup_pids.c

cgroup: pids: fix invalid get/put usage

2015-08-25 14:19:25 -04:00

cgroup.c

Revert "sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem"

2015-09-16 11:51:12 -04:00

compat.c

compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap()

2015-06-04 23:57:18 +02:00

configs.c

…

context_tracking.c

context_tracking: Inherit TIF_NOHZ through forks instead of context switches

2015-05-07 12:02:51 +02:00

cpu_pm.c

kernel/cpu_pm: fix cpu_cluster_pm_exit comment

2015-09-03 02:42:20 +02:00

cpu.c

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

2015-11-03 18:03:50 -08:00

cpuset.c

cpuset: use trialcs->mems_allowed as a temp variable

2015-08-10 11:18:41 -04:00

crash_dump.c

crash_dump: Make is_kdump_kernel() accessible from modules

2014-08-25 15:42:19 -07:00

cred.c

kernel/cred.c: remove unnecessary kdebug atomic reads

2015-09-10 13:29:01 -07:00

delayacct.c

delayacct: Remove braindamaged type conversions

2014-07-23 10:18:06 -07:00

dma.c

…

elfcore.c

…

exec_domain.c

Remove rest of exec domains.

2015-04-12 21:03:31 +02:00

exit.c

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

2015-11-03 18:03:50 -08:00

extable.c

kernel/extable.c: remove duplicated include

2015-09-10 13:29:01 -07:00

fork.c

posix_cpu_timer: Convert cputimer->running to bool

2015-10-15 11:23:41 +02:00

freezer.c

freezer: remove obsolete comments in __thaw_task()

2014-10-21 23:44:20 +02:00

futex_compat.c

…

futex.c

driver core update for 4.4-rc1

2015-11-04 21:50:37 -08:00

groups.c

kernel: conditionally support non-root users, groups and capabilities

2015-04-15 16:35:22 -07:00

hung_task.c

kernel/hung_task.c: change hung_task.c to use for_each_process_thread()

2015-04-15 16:35:22 -07:00

irq_work.c

percpu: Convert remaining __get_cpu_var uses in 3.18-rcX

2014-10-29 11:18:18 -04:00

jump_label.c

locking/static_keys: Add selftest

2015-08-03 11:34:16 +02:00

kallsyms.c

kernel/kallsyms.c: use __seq_open_private()

2014-10-14 02:18:16 +02:00

kcmp.c

kcmp: fix standard comparison bug

2014-09-10 15:42:12 -07:00

Kconfig.freezer

…

Kconfig.hz

…

Kconfig.locks

locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS

2015-05-12 09:46:00 +02:00

Kconfig.preempt

…

kexec_core.c

kexec/crash: Say which char is the unrecognized

2015-10-21 11:10:57 +02:00

kexec_file.c

kexec: split kexec_file syscall code to kexec_file.c

2015-09-10 13:29:01 -07:00

kexec_internal.h

kexec: split kexec_file syscall code to kexec_file.c

2015-09-10 13:29:01 -07:00

kexec.c

kexec: split kexec_load syscall from kexec core code

2015-09-10 13:29:01 -07:00

kmod.c

kmod: don't run async usermode helper as a child of kworker thread

2015-10-23 17:55:10 +09:00

kprobes.c

perf/x86/hw_breakpoints: Disallow kernel breakpoints unless kprobe-safe

2015-08-04 10:16:54 +02:00

ksysfs.c

kexec: split kexec_load syscall from kexec core code

2015-09-10 13:29:01 -07:00

kthread.c

kernel/kthread.c:kthread_create_on_node(): clarify documentation

2015-09-04 16:54:41 -07:00

latencytop.c

kernel/latencytop.c: convert seq_printf to seq_puts

2014-06-04 16:54:15 -07:00

Makefile

sys_membarrier(): system-wide memory barrier (generic, x86)

2015-09-11 15:21:34 -07:00

membarrier.c

sys_membarrier(): system-wide memory barrier (generic, x86)

2015-09-11 15:21:34 -07:00

memremap.c

memremap: fix highmem support

2015-10-26 16:55:56 -04:00

module_signing.c

PKCS#7: Appropriately restrict authenticated attributes and content type

2015-08-12 17:01:01 +01:00

module-internal.h

…

module.c

module: Fix locking in symbol_put_addr()

2015-08-24 10:37:01 +09:30

notifier.c

Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-09-01 08:40:25 -07:00

nsproxy.c

bury struct proc_ns in fs/proc

2014-12-04 14:34:54 -05:00

padata.c

padata: use %*pb[l] to print bitmaps including cpumasks and nodemasks

2015-02-13 21:21:38 -08:00

panic.c

kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path

2015-06-30 19:44:57 -07:00

params.c

Minor merge needed, due to function move.

2015-07-01 10:49:25 -07:00

pid_namespace.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2014-12-16 15:53:03 -08:00

pid.c

rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()

2015-07-22 15:27:32 -07:00

profile.c

mm: rename alloc_pages_exact_node() to __alloc_pages_node()

2015-09-08 15:35:28 -07:00

ptrace.c

seccomp, ptrace: add support for dumping seccomp filters

2015-10-27 19:55:13 -07:00

range.c

kernel: avoid overflow in cmp_range

2015-01-17 10:02:23 +13:00

reboot.c

kexec: split kexec_load syscall from kexec core code

2015-09-10 13:29:01 -07:00

relay.c

kernel/relay.c: use kvfree() in relay_free_page_array()

2015-06-30 19:44:59 -07:00

resource.c

mm: enhance region_is_ram() to region_intersects()

2015-08-10 23:07:05 -04:00

seccomp.c

seccomp, ptrace: add support for dumping seccomp filters

2015-10-27 19:55:13 -07:00

signal.c

signal: fix information leak in copy_siginfo_to_user

2015-08-07 04:39:40 +03:00

smp.c

smp: Fix error case handling in smp_call_function_*()

2015-04-19 13:19:23 -07:00

smpboot.c

stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark()

2015-10-20 10:23:55 +02:00

smpboot.h

…

softirq.c

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

2015-02-09 15:24:03 -08:00

stacktrace.c

stacktrace: introduce snprint_stack_trace for buffer output

2014-12-13 12:42:48 -08:00

stop_machine.c

sched: Move cpu_active() tests from stop_two_cpus() into migrate_swap_stop()

2015-10-20 10:25:56 +02:00

sys_ni.c

sys_membarrier(): system-wide memory barrier (generic, x86)

2015-09-11 15:21:34 -07:00

sys.c

vfs: Commit to never having exectuables on proc and sysfs.

2015-07-10 10:39:25 -05:00

sysctl_binary.c

kernel: add panic_on_warn

2014-12-10 17:41:10 -08:00

sysctl.c

kernel/watchdog.c: add sysctl knob hardlockup_panic

2015-11-05 19:34:48 -08:00

task_work.c

task_work: remove fifo ordering guarantee

2015-09-05 13:46:58 -07:00

taskstats.c

netlink: make nlmsg_end() and genlmsg_end() void

2015-01-18 01:03:45 -05:00

test_kprobes.c

kernel/test_kprobes.c: use current logging functions

2014-08-08 15:57:18 -07:00

torture.c

torture: Consolidate cond_resched_rcu_qs() into stutter_wait()

2015-10-06 11:25:01 -07:00

tracepoint.c

tracing: syscall_regfunc() should not skip kernel threads

2014-06-21 00:15:26 -04:00

tsacct.c

sched: Make task->start_time nanoseconds based

2014-07-23 10:18:05 -07:00

uid16.c

groups: Consolidate the setgroups permission checks

2014-12-05 17:19:27 -06:00

up.c

smp: Rename __smp_call_function_single() to smp_call_function_single_async()

2014-02-24 14:47:15 -08:00

user_namespace.c

capabilities: ambient capabilities

2015-09-04 16:54:41 -07:00

user-return-notifier.c

scheduler: Replace __get_cpu_var with this_cpu_ptr

2014-08-26 13:45:45 -04:00

user.c

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

2014-12-17 12:31:40 -08:00

utsname_sysctl.c

sysctl: convert use of typedef ctl_table to struct ctl_table

2014-06-06 16:08:16 -07:00

utsname.c

copy address of proc_ns_ops into ns_common

2014-12-04 14:34:47 -05:00

watchdog.c

kernel/watchdog.c: avoid race between lockup detector suspend/resume and CPU hotplug

2015-11-05 19:34:48 -08:00

workqueue_internal.h

workqueue: rename manager_mutex to attach_mutex

2014-05-20 10:59:32 -04:00

workqueue.c

workqueue: make sure delayed work run in local cpu

2015-09-30 13:06:46 -04:00