Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Paul E. McKenney 2fd5907775 perf: Disable IRQs across RCU RS CS that acquires scheduler lock ... The perf_lock_task_context() function disables preemption across its RCU read-side critical section because that critical section acquires a scheduler lock. If there was a preemption during that RCU read-side critical section, the rcu_read_unlock() could attempt to acquire scheduler locks, resulting in deadlock. However, recent optimizations to expedited grace periods mean that IPI handlers that execute during preemptible RCU read-side critical sections can now cause the subsequent rcu_read_unlock() to acquire scheduler locks. Disabling preemption does nothiing to prevent these IPI handlers from executing, so these optimizations introduced a deadlock. In theory, this deadlock could be avoided by pulling all wakeups and printk()s out from rnp->lock critical sections, but in practice this would re-introduce some RCU CPU stall warning bugs. Given that acquiring scheduler locks entails disabling interrupts, these deadlocks can be avoided by disabling interrupts (instead of disabling preemption) across any RCU read-side critical that acquires scheduler locks and holds them across the rcu_read_unlock(). This commit therefore makes this change for perf_lock_task_context(). Reported-by: Dave Jones <davej@codemonkey.org.uk> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20151104134838.GR29027@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>		2015-11-09 16:13:11 +01:00
..
bpf	bpf: fix out of bounds access in verifier log	2015-09-09 14:11:55 -07:00
configs	kconfig: add xenconfig defconfig helper	2015-06-16 11:04:29 +01:00
debug
events	perf: Disable IRQs across RCU RS CS that acquires scheduler lock	2015-11-09 16:13:11 +01:00
gcov	gcov: add support for GCC 5.1	2015-06-30 19:44:57 -07:00
irq	Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-11-03 14:40:01 -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	Merge branch 'for-4.3/core' of git://git.kernel.dk/linux-block	2015-09-02 13:10:25 -07:00
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 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-11-03 18:03:50 -08:00
.gitignore
acct.c
async.c
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
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
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
bounds.c
capability.c	kernel: conditionally support non-root users, groups and capabilities	2015-04-15 16:35:22 -07:00
cgroup.c	Revert "sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem"	2015-09-16 11:51:12 -04:00
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
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.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
cpu_pm.c	kernel/cpu_pm: fix cpu_cluster_pm_exit comment	2015-09-03 02:42:20 +02:00
cpuset.c	cpuset: use trialcs->mems_allowed as a temp variable	2015-08-10 11:18:41 -04:00
crash_dump.c
cred.c	kernel/cred.c: remove unnecessary kdebug atomic reads	2015-09-10 13:29:01 -07:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
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
futex.c	futex: Force hot variables into a single cache line	2015-09-22 16:23:15 +02:00
futex_compat.c
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
jump_label.c	locking/static_keys: Add selftest	2015-08-03 11:34:16 +02:00
kallsyms.c
kcmp.c
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.c	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
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
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
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-internal.h
module.c	module: Fix locking in symbol_put_addr()	2015-08-24 10:37:01 +09:30
module_signing.c	PKCS#7: Appropriately restrict authenticated attributes and content type	2015-08-12 17:01:01 +01:00
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
padata.c
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.c	rcu: Rename rcu_lockdep_assert() to RCU_LOCKDEP_WARN()	2015-07-22 15:27:32 -07:00
pid_namespace.c
profile.c	mm: rename alloc_pages_exact_node() to __alloc_pages_node()	2015-09-08 15:35:28 -07:00
ptrace.c	seccomp: add ptrace options for suspend/resume	2015-07-15 11:52:52 -07:00
range.c
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	Merge tag 'seccomp-next' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into next	2015-07-20 17:19:19 +10:00
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
stacktrace.c
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.c	vfs: Commit to never having exectuables on proc and sysfs.	2015-07-10 10:39:25 -05:00
sys_ni.c	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
sysctl.c	sysctl: fix int -> unsigned long assignments in INT_MIN case	2015-09-10 13:29:01 -07:00
sysctl_binary.c
task_work.c	task_work: remove fifo ordering guarantee	2015-09-05 13:46:58 -07:00
taskstats.c
test_kprobes.c
torture.c	torture: Consolidate cond_resched_rcu_qs() into stutter_wait()	2015-10-06 11:25:01 -07:00
tracepoint.c
tsacct.c
uid16.c
up.c
user-return-notifier.c
user.c
user_namespace.c	capabilities: ambient capabilities	2015-09-04 16:54:41 -07:00
utsname.c
utsname_sysctl.c
watchdog.c	watchdog: rename watchdog_suspend() and watchdog_resume()	2015-09-04 16:54:41 -07:00
workqueue.c	workqueue: make sure delayed work run in local cpu	2015-09-30 13:06:46 -04:00
workqueue_internal.h