Tetsuo Handa 7f1a169b88 sched/fair: Fix RCU stall upon -ENOMEM in sched_create_group() ... When alloc_fair_sched_group() in sched_create_group() fails, free_sched_group() is called, and free_fair_sched_group() is called by free_sched_group(). Since destroy_cfs_bandwidth() is called by free_fair_sched_group() without calling init_cfs_bandwidth(), RCU stall occurs at hrtimer_cancel(): INFO: rcu_sched self-detected stall on CPU { 1} (t=60000 jiffies g=13074 c=13073 q=0) Task dump for CPU 1: (fprintd) R running task 0 6249 1 0x00000088 ... Call Trace: <IRQ> [<ffffffff81094988>] sched_show_task+0xa8/0x110 [<ffffffff81097acd>] dump_cpu_task+0x3d/0x50 [<ffffffff810c3a80>] rcu_dump_cpu_stacks+0x90/0xd0 [<ffffffff810c7751>] rcu_check_callbacks+0x491/0x700 [<ffffffff810cbf2b>] update_process_times+0x4b/0x80 [<ffffffff810db046>] tick_sched_handle.isra.20+0x36/0x50 [<ffffffff810db0a2>] tick_sched_timer+0x42/0x70 [<ffffffff810ccb19>] __run_hrtimer+0x69/0x1a0 [<ffffffff810db060>] ? tick_sched_handle.isra.20+0x50/0x50 [<ffffffff810ccedf>] hrtimer_interrupt+0xef/0x230 [<ffffffff810452cb>] local_apic_timer_interrupt+0x3b/0x70 [<ffffffff8164a465>] smp_apic_timer_interrupt+0x45/0x60 [<ffffffff816485bd>] apic_timer_interrupt+0x6d/0x80 <EOI> [<ffffffff810cc588>] ? lock_hrtimer_base.isra.23+0x18/0x50 [<ffffffff81193cf1>] ? __kmalloc+0x211/0x230 [<ffffffff810cc9d2>] hrtimer_try_to_cancel+0x22/0xd0 [<ffffffff81193cf1>] ? __kmalloc+0x211/0x230 [<ffffffff810ccaa2>] hrtimer_cancel+0x22/0x30 [<ffffffff810a3cb5>] free_fair_sched_group+0x25/0xd0 [<ffffffff8108df46>] free_sched_group+0x16/0x40 [<ffffffff810971bb>] sched_create_group+0x4b/0x80 [<ffffffff810aa383>] sched_autogroup_create_attach+0x43/0x1c0 [<ffffffff8107dc9c>] sys_setsid+0x7c/0x110 [<ffffffff81647729>] system_call_fastpath+0x12/0x17 Check whether init_cfs_bandwidth() was called before calling destroy_cfs_bandwidth(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [ Move the check into destroy_cfs_bandwidth() to aid compilability. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Paul Turner <pjt@google.com> Cc: Ben Segall <bsegall@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/201412252210.GCC30204.SOMVFFOtQJFLOH@I-love.SAKURA.ne.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>		2015-01-09 11:19:00 +01:00
..
auto_group.c
auto_group.h
clock.c
completion.c
core.c	sched: Fix KMALLOC_MAX_SIZE overflow during cpumask allocation	2014-12-23 11:43:48 +01:00
cpuacct.c
cpuacct.h
cpudeadline.c
cpudeadline.h
cpupri.c
cpupri.h
cputime.c
deadline.c	sched/deadline: Avoid double-accounting in case of missed deadlines	2015-01-09 11:18:57 +01:00
debug.c
fair.c	sched/fair: Fix RCU stall upon -ENOMEM in sched_create_group()	2015-01-09 11:19:00 +01:00
features.h
idle.c
idle_task.c
Makefile
proc.c
rt.c
sched.h
stats.c
stats.h
stop_task.c
wait.c