BUG: sleeping function called from invalid context at kernel/stop_machine.c:135

[Daniel Bristot de Oliveira <bristot@redhat.com>]

Hi Waiman,

Are you aware of this issue:
----- %< -----
[   88.307857] BUG: sleeping function called from invalid context at kernel/stop_machine.c:135
[   88.308796] in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 801, name: sh
[   88.309785] 6 locks held by sh/801:
[   88.310265]  #0: ffff9f008c575460 (sb_writers#7){.+.+}-{0:0}, at: ksys_write+0x58/0xd0
[   88.310906]  #1: ffff9f008e9dd088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write+0xa5/0x1c0
[   88.311672]  #2: ffff9f0092164a88 (kn->active#195){.+.+}-{0:0}, at: kernfs_fop_write+0xad/0x1c0
[   88.312456]  #3: ffffffffbac68310 (cpu_hotplug_lock){++++}-{0:0}, at: sched_partition_write+0x72/0x2f0
[   88.313280]  #4: ffffffffbae37090 (&cpuset_rwsem){++++}-{0:0}, at: sched_partition_write+0x7e/0x2f0
[   88.314095]  #5: ffffffffbad89140 (rcu_read_lock){....}-{1:3}, at: update_sibling_cpumasks+0x5/0x140
[   88.314806] Preemption disabled at:
[   88.314810] [<ffffffffb900454d>] preempt_schedule_thunk+0x16/0x18
[   88.315815] CPU: 1 PID: 801 Comm: sh Not tainted 5.10.0-rc5+ #10
[   88.316203] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
[   88.316714] Call Trace:
[   88.316875]  dump_stack+0x8b/0xb0
[   88.317087]  ___might_sleep.cold+0x102/0x116
[   88.317354]  stop_one_cpu+0x82/0xa0
[   88.317578]  ? set_cpus_allowed_ptr+0x10/0x10
[   88.317858]  __set_cpus_allowed_ptr+0x1e6/0x1f0
[   88.318144]  update_tasks_cpumask+0x25/0x50
[   88.318415]  update_cpumasks_hier+0x257/0x840
[   88.318687]  update_sibling_cpumasks+0x96/0x140
[   88.318968]  update_prstate+0x1a0/0x1f0
[   88.319210]  sched_partition_write+0x9f/0x2f0
[   88.319482]  kernfs_fop_write+0xdc/0x1c0
[   88.319730]  vfs_write+0xea/0x3b0
[   88.319943]  ksys_write+0x58/0xd0
[   88.320156]  do_syscall_64+0x33/0x40
[   88.320382]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   88.320692] RIP: 0033:0x7fbbd79be537
[   88.320915] Code: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04
		     25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3
		     48 83 ec 28 48 89 54 24 18 48 89 74 24
[   88.322028] RSP: 002b:00007ffd44cc8398 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   88.322479] RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fbbd79be537
[   88.322910] RDX: 0000000000000005 RSI: 0000558ae69200a0 RDI: 0000000000000001
[   88.323342] RBP: 0000558ae69200a0 R08: 000000000000000a R09: 0000000000000004
[   88.323775] R10: 0000558ae6921ba0 R11: 0000000000000246 R12: 0000000000000005
[   88.325046] R13: 00007fbbd7a90500 R14: 0000000000000005 R15: 00007fbbd7a90700
----- >% -----

it happens when I run this (from Dietmar):
----- %< -----
cd /sys/fs/cgroup/

echo $$ > cgroup.procs

echo +cpuset > cgroup.subtree_control
chrt -d --sched-period 1000000000 --sched-runtime 100000000 0 sleep 500 &
PID1=$!
chrt -d --sched-period 1000000000 --sched-runtime 100000000 0 sleep 500 &
PID2=$!

sleep 3

mkdir A
echo 0 > ./A/cpuset.mems
echo 0 > ./A/cpuset.cpus

echo $PID2 > ./A/cgroup.procs
echo root > ./A/cpuset.cpus.partition
echo $PID2 > ./A/cgroup.procs

cat /proc/$PID1/status | grep Cpus_allowed_list | awk '{print $2}'

cat /proc/$PID2/status | grep Cpus_allowed_list | awk '{print $2}'
----- >% -----

with this kernel config:
https://bristot.me/lkml/20200119/config.txt

on Fedora 32 (x86 64 vm).

full dmesg here:
https://bristot.me/lkml/20200119/dmesg.txt

-- Daniel