Oleg Nesterov 13c22168b7 destroy_workqueue() can livelock ... Pointed out by Michal Schmidt <mschmidt@redhat.com>. The bug was introduced in 2.6.22 by me. cleanup_workqueue_thread() does flush_cpu_workqueue(cwq) in a loop until ->worklist becomes empty. This is live-lockable, a re-niced caller can get CPU after wake_up() and insert a new barrier before the lower-priority cwq->thread has a chance to clear ->current_work. Change cleanup_workqueue_thread() to do flush_cpu_workqueue(cwq) only once. We can rely on the fact that run_workqueue() won't return until it flushes all works. So it is safe to call kthread_stop() after that, the "should stop" request won't be noticed until run_workqueue() returns. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Michal Schmidt <mschmidt@redhat.com> Cc: Srivatsa Vaddagiri <vatsa@in.ibm.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2007-07-17 10:23:03 -07:00
..
irq	Improve behaviour of spurious IRQ detect	2007-07-16 09:05:46 -07:00
power
time	kallsyms: make KSYM_NAME_LEN include space for trailing '\0'	2007-07-17 10:23:03 -07:00
.gitignore
acct.c
audit.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
audit.h	Audit: add TTY input auditing	2007-07-16 09:05:47 -07:00
auditfilter.c
auditsc.c	kerneldoc fix in audit_core_dumps	2007-07-16 09:05:48 -07:00
capability.c
compat.c
configs.c
cpu.c
cpuset.c	Reduce cpuset.c write_lock_irq() to read_lock()	2007-07-16 09:05:43 -07:00
delayacct.c
die_notifier.c
dma.c
exec_domain.c
exit.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
extable.c
fork.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
futex_compat.c
futex.c	FUTEX: Tidy up the code	2007-07-16 09:05:49 -07:00
hrtimer.c	[HRTIMER] Fix cpu pointer arg to clockevents_notify()	2007-07-16 17:29:56 -07:00
itimer.c
kallsyms.c	kallsyms: make KSYM_NAME_LEN include space for trailing '\0'	2007-07-17 10:23:03 -07:00
Kconfig.hz
Kconfig.preempt
kexec.c
kfifo.c	is_power_of_2: kernel/kfifo.c	2007-07-16 09:05:50 -07:00
kmod.c
kprobes.c
ksysfs.c
kthread.c	mm: fix improper .init-type section references	2007-07-16 09:05:36 -07:00
latency.c
lockdep_internals.h
lockdep_proc.c
lockdep.c	kallsyms: make KSYM_NAME_LEN include space for trailing '\0'	2007-07-17 10:23:03 -07:00
Makefile	user namespace: add the framework	2007-07-16 09:05:47 -07:00
module.c	kallsyms: make KSYM_NAME_LEN include space for trailing '\0'	2007-07-17 10:23:03 -07:00
mutex-debug.c
mutex-debug.h
mutex.c
mutex.h
nsproxy.c	namespace: ensure clone_flags are always stored in an unsigned long	2007-07-16 09:05:48 -07:00
panic.c	Report that kernel is tainted if there was an OOPS	2007-07-17 10:23:02 -07:00
params.c
pid.c	namespace: ensure clone_flags are always stored in an unsigned long	2007-07-16 09:05:48 -07:00
posix-cpu-timers.c
posix-timers.c
printk.c	kernel/printk.c: document possible deadlock against scheduler	2007-07-16 09:05:52 -07:00
profile.c
ptrace.c	PTRACE_POKEDATA consolidation	2007-07-17 10:23:03 -07:00
rcupdate.c
rcutorture.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
relay.c
resource.c
rtmutex_common.h	FUTEX: Tidy up the code	2007-07-16 09:05:49 -07:00
rtmutex-debug.c	FUTEX: Tidy up the code	2007-07-16 09:05:49 -07:00
rtmutex-debug.h
rtmutex-tester.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
rtmutex.c	FUTEX: Tidy up the code	2007-07-16 09:05:49 -07:00
rtmutex.h
rwsem.c
sched_debug.c
sched_fair.c
sched_idletask.c
sched_rt.c
sched_stats.h
sched.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
seccomp.c	make seccomp zerocost in schedule	2007-07-16 09:05:50 -07:00
signal.c	vdso: print fatal signals	2007-07-16 09:05:43 -07:00
softirq.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
softlockup.c	Freezer: make kernel threads nonfreezable by default	2007-07-17 10:23:02 -07:00
spinlock.c
srcu.c
stacktrace.c
stop_machine.c	Fix stop_machine_run problem with naughty real time process	2007-07-16 09:05:41 -07:00
sys_ni.c	diskquota: 32bit quota tools on 64bit architectures	2007-07-16 09:05:48 -07:00
sys.c	move seccomp from /proc to a prctl	2007-07-16 09:05:50 -07:00
sysctl.c	proper prototype for proc_nr_files()	2007-07-17 10:23:03 -07:00
taskstats.c	taskstats: add context-switch counters	2007-07-16 09:05:46 -07:00
time.c	sys_time() speedup	2007-07-16 09:05:48 -07:00
timer.c	Slab allocators: Replace explicit zeroing with __GFP_ZERO	2007-07-17 10:23:02 -07:00
tsacct.c
uid16.c
user_namespace.c	fix create_new_namespaces() return value	2007-07-16 09:05:47 -07:00
user.c	user namespace: add the framework	2007-07-16 09:05:47 -07:00
utsname_sysctl.c	remove CONFIG_UTS_NS and CONFIG_IPC_NS	2007-07-16 09:05:47 -07:00
utsname.c	namespace: ensure clone_flags are always stored in an unsigned long	2007-07-16 09:05:48 -07:00
wait.c
workqueue.c	destroy_workqueue() can livelock	2007-07-17 10:23:03 -07:00