Oleg Nesterov 5d8f72b55c freezer: change ptrace_stop/do_signal_stop to use freezable_schedule() ... try_to_freeze_tasks() and cgroup_freezer rely on scheduler locks to ensure that a task doing STOPPED/TRACED -> RUNNING transition can't escape freezing. This mostly works, but ptrace_stop() does not necessarily call schedule(), it can change task->state back to RUNNING and check freezing() without any lock/barrier in between. We could add the necessary barrier, but this patch changes ptrace_stop() and do_signal_stop() to use freezable_schedule(). This fixes the race, freezer_count() and freezer_should_skip() carefully avoid the race. And this simplifies the code, try_to_freeze_tasks/update_if_frozen no longer need to use task_is_stopped_or_traced() checks with the non trivial assumptions. We can rely on the mechanism which was specially designed to mark the sleeping task as "frozen enough". v2: As Tejun pointed out, we can also change get_signal_to_deliver() and move try_to_freeze() up before 'relock' label. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>		2012-10-26 14:27:49 -07:00
..
debug	KGDB/KDB fixes and cleanups	2012-10-13 11:16:58 +09:00
events	Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-10-13 10:20:11 +09:00
gcov
irq	irqdomain: augment add_simple() to allocate descs	2012-10-10 08:57:26 +02:00
power	freezer: change ptrace_stop/do_signal_stop to use freezable_schedule()	2012-10-26 14:27:49 -07:00
sched	Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-10-12 22:13:05 +09:00
time	Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-10-12 22:17:48 +09:00
trace	Merge branch 'virtio-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux	2012-10-07 21:04:56 +09:00
.gitignore
acct.c	vfs: make path_openat take a struct filename pointer	2012-10-12 20:15:09 -04:00
async.c
audit_tree.c
audit_watch.c	audit: optimize audit_compare_dname_path	2012-10-12 00:32:02 -04:00
audit.c	fs: handle failed audit_log_start properly	2012-10-09 23:33:37 -04:00
audit.h	audit: optimize audit_compare_dname_path	2012-10-12 00:32:02 -04:00
auditfilter.c	audit: optimize audit_compare_dname_path	2012-10-12 00:32:02 -04:00
auditsc.c	audit: make audit_inode take struct filename	2012-10-12 20:15:09 -04:00
backtracetest.c
bounds.c
capability.c
cgroup_freezer.c	freezer: change ptrace_stop/do_signal_stop to use freezable_schedule()	2012-10-26 14:27:49 -07:00
cgroup.c	cgroup: cgroup_subsys->fork() should be called after the task is added to css_set	2012-10-16 15:03:14 -07:00
compat.c
configs.c
cpu_pm.c
cpu.c	CPU hotplug, debug: detect imbalance between get_online_cpus() and put_online_cpus()	2012-10-09 16:22:15 +09:00
cpuset.c
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2012-10-02 20:25:04 -07:00
extable.c
fork.c	cgroup: cgroup_subsys->fork() should be called after the task is added to css_set	2012-10-16 15:03:14 -07:00
freezer.c	freezer: change ptrace_stop/do_signal_stop to use freezable_schedule()	2012-10-26 14:27:49 -07:00
futex_compat.c
futex.c
groups.c
hrtimer.c
hung_task.c
irq_work.c
itimer.c
jump_label.c
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kdump: remove unneeded include	2012-10-06 03:05:19 +09:00
kfifo.c
kmod.c	infrastructure for saner ret_from_kernel_thread semantics	2012-10-12 13:35:07 -04:00
kprobes.c
ksysfs.c
kthread.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal	2012-10-13 10:05:52 +09:00
latencytop.c
lglock.c
lockdep_internals.h
lockdep_proc.c
lockdep_states.h
lockdep.c
Makefile	Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux	2012-10-14 13:39:34 -07:00
modsign_pubkey.c	MODSIGN: Provide module signing public keys to the kernel	2012-10-10 20:01:22 +10:30
module_signing.c	MODSIGN: Implement module signature checking	2012-10-10 20:06:10 +10:30
module-internal.h	MODSIGN: Provide module signing public keys to the kernel	2012-10-10 20:01:22 +10:30
module.c	MODSIGN: Add FIPS policy	2012-10-10 20:01:19 +10:30
mutex-debug.c
mutex-debug.h
mutex.c
mutex.h
notifier.c
nsproxy.c
padata.c
panic.c
params.c
pid_namespace.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2012-10-02 11:11:09 -07:00
pid.c
posix-cpu-timers.c
posix-timers.c
printk.c
profile.c
ptrace.c
range.c
rcu.h
rcupdate.c
rcutiny_plugin.h
rcutiny.c
rcutorture.c
rcutree_plugin.h
rcutree_trace.c
rcutree.c	rcu: Grace-period initialization excludes only RCU notifier	2012-10-08 09:06:38 -07:00
rcutree.h	rcu: Grace-period initialization excludes only RCU notifier	2012-10-08 09:06:38 -07:00
relay.c
res_counter.c
resource.c	kernel/resource.c: fix stack overflow in __reserve_region_with_split()	2012-10-06 03:05:31 +09:00
rtmutex_common.h
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c
rtmutex.h
rwsem.c
seccomp.c
semaphore.c
signal.c	freezer: change ptrace_stop/do_signal_stop to use freezable_schedule()	2012-10-26 14:27:49 -07:00
smp.c
smpboot.c
smpboot.h
softirq.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2012-10-01 10:43:39 -07:00
spinlock.c
srcu.c
stacktrace.c
stop_machine.c
sys_ni.c
sys.c	poweroff: fix bug in orderly_poweroff()	2012-10-06 03:04:48 +09:00
sysctl_binary.c
sysctl.c	Kconfig: clean up the "#if defined(arch)" list for exception-trace sysctl entry	2012-10-09 16:22:14 +09:00
task_work.c
taskstats.c	taskstats: cgroupstats_user_cmd() may leak on error	2012-10-06 03:05:31 +09:00
test_kprobes.c
time.c
timeconst.pl
timer.c	timers: Fix endless looping between cascade() and internal_add_timer()	2012-10-09 21:27:14 +02:00
tracepoint.c
tsacct.c
uid16.c
up.c
user_namespace.c
user-return-notifier.c
user.c
utsname_sysctl.c
utsname.c
wait.c
watchdog.c
workqueue_sched.h
workqueue.c	Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq	2012-10-02 09:54:49 -07:00