INFO: rcu detected stall in lock_is_held_type

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cbfa1702 Linux 4.14.198
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11eb46c5900000
kernel config: https://syzkaller.appspot.com/x/.config?x=3990958d85b55e59
dashboard link: https://syzkaller.appspot.com/bug?extid=8d821f09d13960b0d8c9
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8d821f...@syzkaller.appspotmail.com

INFO: rcu_preempt detected stalls on CPUs/tasks:
(detected by 1, t=10502 jiffies, g=2421, c=2420, q=854)
All QSes seen, last rcu_preempt kthread activity 10500 (4294962936-4294952436), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor.2 R running task 27688 9164 6367 0x80000008
Call Trace:
<IRQ>
sched_show_task.cold+0x333/0x39a kernel/sched/core.c:5169
print_other_cpu_stall kernel/rcu/tree.c:1501 [inline]
check_cpu_stall kernel/rcu/tree.c:1616 [inline]
__rcu_pending kernel/rcu/tree.c:3390 [inline]
rcu_pending kernel/rcu/tree.c:3452 [inline]
rcu_check_callbacks.cold+0xd29/0xd99 kernel/rcu/tree.c:2792
update_process_times+0x28/0xa0 kernel/time/timer.c:1591
tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165
tick_sched_timer+0x92/0x200 kernel/time/tick-sched.c:1223
__run_hrtimer kernel/time/hrtimer.c:1223 [inline]
__hrtimer_run_queues+0x30b/0xc80 kernel/time/hrtimer.c:1287
hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100
apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:lock_is_held_type+0x17a/0x210 kernel/locking/lockdep.c:4038
RSP: 0018:ffff8880aeb07d08 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0fa2d21 RBX: 0000000000000286 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 00000000ffffffff RDI: 0000000000000286
RBP: ffff8880542a62c0 R08: ffffffff8a734748 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 1ffff11015d60fac R14: 1ffff11015d60fd1 R15: 0000000000000001
lock_is_held include/linux/lockdep.h:437 [inline]
rcu_read_lock_sched_held+0x16c/0x1d0 kernel/rcu/update.c:116
trace_timer_expire_exit include/trace/events/timer.h:121 [inline]
call_timer_fn+0x515/0x650 kernel/time/timer.c:1281
expire_timers+0x232/0x4d0 kernel/time/timer.c:1319
__run_timers kernel/time/timer.c:1644 [inline]
run_timer_softirq+0x1d5/0x5a0 kernel/time/timer.c:1657
__do_softirq+0x254/0xa1d kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x193/0x240 kernel/softirq.c:409
exiting_irq arch/x86/include/asm/apic.h:648 [inline]
smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102
apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
</IRQ>
RIP: 0010:static_protections arch/x86/mm/pageattr.c:346 [inline]
RIP: 0010:try_preserve_large_page arch/x86/mm/pageattr.c:613 [inline]
RIP: 0010:__change_page_attr arch/x86/mm/pageattr.c:1273 [inline]
RIP: 0010:__change_page_attr_set_clr+0xdf4/0x2280 arch/x86/mm/pageattr.c:1393
RSP: 0018:ffff888049217590 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000040000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff81295937 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff8a0bc1d0 R09: 000000000004000d
R10: ffff8880542a6b70 R11: ffff8880542a62c0 R12: ffff888047f22000
R13: 0000000000047f22 R14: 0000000000040000 R15: 80000000000001e1
cpa_process_alias arch/x86/mm/pageattr.c:1345 [inline]
__change_page_attr_set_clr+0x1a45/0x2280 arch/x86/mm/pageattr.c:1400
change_page_attr_set_clr+0x2a2/0xa30 arch/x86/mm/pageattr.c:1489
change_page_attr_clear arch/x86/mm/pageattr.c:1532 [inline]
set_memory_ro+0x68/0x80 arch/x86/mm/pageattr.c:1761
bpf_jit_binary_lock_ro include/linux/filter.h:628 [inline]
bpf_int_jit_compile+0x441/0x5fe arch/x86/net/bpf_jit_comp.c:1204
bpf_prog_select_runtime+0xdf/0x4e0 kernel/bpf/core.c:1455
bpf_prog_load+0x646/0x1050 kernel/bpf/syscall.c:1062
SYSC_bpf kernel/bpf/syscall.c:1512 [inline]
SyS_bpf+0x1336/0x3590 kernel/bpf/syscall.c:1477
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45e179
RSP: 002b:00007fbc42c1ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000001cc0 RCX: 000000000045e179
RDX: 0000000000000048 RSI: 0000000020000080 RDI: 0000000000000005
RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffea4e36fbf R14: 00007fbc42c1b9c0 R15: 000000000118cf4c
rcu_preempt kthread starved for 10549 jiffies! g2421 c2420 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
rcu_preempt R running task 30008 8 2 0x80000000
Call Trace:
context_switch kernel/sched/core.c:2808 [inline]
__schedule+0x88b/0x1de0 kernel/sched/core.c:3384
schedule+0x8d/0x1b0 kernel/sched/core.c:3428
schedule_timeout+0x4af/0xe90 kernel/time/timer.c:1754
rcu_gp_kthread+0xc0a/0x1e60 kernel/rcu/tree.c:2255
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.