4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Peter Zijlstra <pet...@infradead.org>
[ Upstream commit 1b1d62254df0fe42a711eb71948f915918987790 ]
Bug was noticed via this warning:
WARNING: CPU: 6 PID: 1 at kernel/sched/sched.h:804
detach_task_cfs_rq+0x8e8/0xb80
rq->clock_update_flags < RQCF_ACT_SKIP
Modules linked in:
CPU: 6 PID: 1 Comm: systemd Not tainted 4.10.0-rc5-00140-g0874170baf55-dirty
#1
Hardware name: Supermicro SYS-4048B-TRFT/X10QBi, BIOS 1.0 04/11/2014
Call Trace:
dump_stack+0x4d/0x65
__warn+0xcb/0xf0
warn_slowpath_fmt+0x5f/0x80
detach_task_cfs_rq+0x8e8/0xb80
? allocate_cgrp_cset_links+0x59/0x80
task_change_group_fair+0x27/0x150
sched_change_group+0x48/0xf0
sched_move_task+0x53/0x150
cpu_cgroup_attach+0x36/0x70
cgroup_taskset_migrate+0x175/0x300
cgroup_migrate+0xab/0xd0
cgroup_attach_task+0xf0/0x190
__cgroup_procs_write+0x1ed/0x2f0
cgroup_procs_write+0x14/0x20
cgroup_file_write+0x3f/0x100
kernfs_fop_write+0x104/0x180
__vfs_write+0x37/0x140
vfs_write+0xb8/0x1b0
SyS_write+0x55/0xc0
do_syscall_64+0x61/0x170
entry_SYSCALL64_slow_path+0x25/0x25
Reported-by: Ingo Molnar <mi...@kernel.org>
Reported-by: Borislav Petkov <b...@alien8.de>
Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Mike Galbraith <efa...@gmx.de>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Signed-off-by: Ingo Molnar <mi...@kernel.org>
Signed-off-by: Sasha Levin <alexander.le...@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
kernel/sched/core.c | 1 +
1 file changed, 1 insertion(+)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7961,6 +7961,7 @@ void sched_move_task(struct task_struct
struct rq *rq;
rq = task_rq_lock(tsk, &rf);
+ update_rq_clock(rq);
running = task_current(rq, tsk);
queued = task_on_rq_queued(tsk);
