WARNING: ODEBUG bug in enqueue_hrtimer
From: syzbot
Date: Tue Jul 31 2018 - 08:31:08 EST
Hello,
syzbot found the following crash on:
HEAD commit: 527838d470e3 Merge branch 'x86-urgent-for-linus' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15e90362400000
kernel config: https://syzkaller.appspot.com/x/.config?x=2dc0cd7c2eefb46f
dashboard link: https://syzkaller.appspot.com/bug?extid=3c31c6798616dc2d9ee6
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3c31c6798616dc2d9ee6@xxxxxxxxxxxxxxxxxxxxxxxxx
netlink: 20 bytes leftover after parsing attributes in process
`syz-executor3'.
------------[ cut here ]------------
ODEBUG: activate not available (active state 0) object type: hrtimer hint:
bcm_tx_timeout_handler+0x0/0x60 net/can/bcm.c:241
WARNING: CPU: 1 PID: 18 at lib/debugobjects.c:329
debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.18.0-rc7+ #170
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
panic+0x238/0x4e7 kernel/panic.c:184
__warn.cold.8+0x163/0x1ba kernel/panic.c:536
report_bug+0x252/0x2d0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:178 [inline]
do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
RIP: 0010:debug_print_object+0x16a/0x210 lib/debugobjects.c:326
Code: 3a 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 92 00 00 00 48 8b 14 dd
20 74 3a 87 4c 89 f6 48 c7 c7 c0 69 3a 87 e8 c6 b0 e6 fd <0f> 0b 83 05 a9
e6 29 05 01 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffff8801d9f27680 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000000
RDX: 0000000000000100 RSI: ffffffff81632481 RDI: 0000000000000001
RBP: ffff8801d9f276c0 R08: ffff8801d9f0c4c0 R09: ffffed003b623ec2
R10: ffffed003b623ec2 R11: ffff8801db11f617 R12: 0000000000000001
R13: ffffffff87fa0660 R14: ffffffff873a7040 R15: ffffffff816a48f0
debug_object_activate+0x359/0x690 lib/debugobjects.c:513
debug_hrtimer_activate kernel/time/hrtimer.c:416 [inline]
debug_activate kernel/time/hrtimer.c:465 [inline]
enqueue_hrtimer+0x9e/0x540 kernel/time/hrtimer.c:954
__hrtimer_start_range_ns kernel/time/hrtimer.c:1089 [inline]
hrtimer_start_range_ns+0x616/0xd20 kernel/time/hrtimer.c:1115
hrtimer_start include/linux/hrtimer.h:398 [inline]
bcm_tx_start_timer+0x11d/0x1b0 net/can/bcm.c:361
bcm_tx_timeout_tsklet+0x1ab/0x4b0 net/can/bcm.c:392
tasklet_action_common.isra.19+0x26f/0x720 kernel/softirq.c:522
tasklet_action+0x1d/0x20 kernel/softirq.c:540
__do_softirq+0x2e8/0xb17 kernel/softirq.c:292
run_ksoftirqd+0x86/0x100 kernel/softirq.c:653
smpboot_thread_fn+0x417/0x870 kernel/smpboot.c:164
kthread+0x345/0x410 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
======================================================
WARNING: possible circular locking dependency detected
4.18.0-rc7+ #170 Not tainted
------------------------------------------------------
ksoftirqd/1/18 is trying to acquire lock:
000000006298a4a7 ((console_sem).lock){-.-.}, at: down_trylock+0x13/0x70
kernel/locking/semaphore.c:136
but task is already holding lock:
0000000018a38b75 (hrtimer_bases.lock){-.-.}, at:
lock_hrtimer_base.isra.18+0x75/0x130 kernel/time/hrtimer.c:174
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #4 (hrtimer_bases.lock){-.-.}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
lock_hrtimer_base.isra.18+0x75/0x130 kernel/time/hrtimer.c:174
hrtimer_start_range_ns+0x128/0xd20 kernel/time/hrtimer.c:1113
hrtimer_start_expires include/linux/hrtimer.h:412 [inline]
start_rt_bandwidth kernel/sched/rt.c:68 [inline]
inc_rt_group kernel/sched/rt.c:1147 [inline]
inc_rt_tasks kernel/sched/rt.c:1191 [inline]
__enqueue_rt_entity kernel/sched/rt.c:1261 [inline]
enqueue_rt_entity kernel/sched/rt.c:1305 [inline]
enqueue_task_rt+0x96a/0xfd0 kernel/sched/rt.c:1335
enqueue_task+0xa2/0x1d0 kernel/sched/core.c:750
__sched_setscheduler+0xe80/0x20b0 kernel/sched/core.c:4365
_sched_setscheduler+0x20c/0x370 kernel/sched/core.c:4402
sched_setscheduler+0xe/0x10 kernel/sched/core.c:4417
watchdog_set_prio kernel/watchdog.c:455 [inline]
watchdog_enable+0x12d/0x1a0 kernel/watchdog.c:477
smpboot_thread_fn+0x4c0/0x870 kernel/smpboot.c:145
kthread+0x345/0x410 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
-> #3 (&rt_b->rt_runtime_lock){-.-.}:
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
start_rt_bandwidth kernel/sched/rt.c:56 [inline]
inc_rt_group kernel/sched/rt.c:1147 [inline]
inc_rt_tasks kernel/sched/rt.c:1191 [inline]
__enqueue_rt_entity kernel/sched/rt.c:1261 [inline]
enqueue_rt_entity kernel/sched/rt.c:1305 [inline]
enqueue_task_rt+0x618/0xfd0 kernel/sched/rt.c:1335
enqueue_task+0xa2/0x1d0 kernel/sched/core.c:750
__sched_setscheduler+0xe80/0x20b0 kernel/sched/core.c:4365
_sched_setscheduler+0x20c/0x370 kernel/sched/core.c:4402
sched_setscheduler+0xe/0x10 kernel/sched/core.c:4417
watchdog_set_prio kernel/watchdog.c:455 [inline]
watchdog_enable+0x12d/0x1a0 kernel/watchdog.c:477
smpboot_thread_fn+0x4c0/0x870 kernel/smpboot.c:145
kthread+0x345/0x410 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
-> #2 (&rq->lock){-.-.}:
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
rq_lock kernel/sched/sched.h:1812 [inline]
task_fork_fair+0x93/0x680 kernel/sched/fair.c:9952
sched_fork+0x446/0xb40 kernel/sched/core.c:2381
copy_process.part.39+0x1bf5/0x70b0 kernel/fork.c:1796
copy_process kernel/fork.c:1639 [inline]
_do_fork+0x291/0x12a0 kernel/fork.c:2122
kernel_thread+0x34/0x40 kernel/fork.c:2181
rest_init+0x22/0xe4 init/main.c:408
start_kernel+0x90e/0x949 init/main.c:738
x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:452
x86_64_start_kernel+0x76/0x79 arch/x86/kernel/head64.c:433
secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:242
-> #1 (&p->pi_lock){-.-.}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
try_to_wake_up+0xd2/0x12a0 kernel/sched/core.c:1985
wake_up_process+0x10/0x20 kernel/sched/core.c:2148
__up.isra.1+0x1c0/0x2a0 kernel/locking/semaphore.c:262
up+0x13c/0x1c0 kernel/locking/semaphore.c:187
__up_console_sem+0xbe/0x1b0 kernel/printk/printk.c:242
console_unlock+0x7a2/0x10b0 kernel/printk/printk.c:2411
vprintk_emit+0x6c6/0xdf0 kernel/printk/printk.c:1907
vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
printk+0xa7/0xcf kernel/printk/printk.c:1981
load_umh+0x51/0xbd net/bpfilter/bpfilter_kern.c:98
do_one_initcall+0x127/0x913 init/main.c:884
do_initcall_level init/main.c:952 [inline]
do_initcalls init/main.c:960 [inline]
do_basic_setup init/main.c:978 [inline]
kernel_init_freeable+0x49b/0x58e init/main.c:1135
kernel_init+0x11/0x1b3 init/main.c:1061
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
-> #0 ((console_sem).lock){-.-.}:
lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
__down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225
console_trylock+0x15/0xa0 kernel/printk/printk.c:2230
console_trylock_spinning kernel/printk/printk.c:1643 [inline]
vprintk_emit+0x6ad/0xdf0 kernel/printk/printk.c:1906
vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
printk+0xa7/0xcf kernel/printk/printk.c:1981
__warn_printk+0x8c/0xe0 kernel/panic.c:590
debug_print_object+0x16a/0x210 lib/debugobjects.c:326
debug_object_activate+0x359/0x690 lib/debugobjects.c:513
debug_hrtimer_activate kernel/time/hrtimer.c:416 [inline]
debug_activate kernel/time/hrtimer.c:465 [inline]
enqueue_hrtimer+0x9e/0x540 kernel/time/hrtimer.c:954
__hrtimer_start_range_ns kernel/time/hrtimer.c:1089 [inline]
hrtimer_start_range_ns+0x616/0xd20 kernel/time/hrtimer.c:1115
hrtimer_start include/linux/hrtimer.h:398 [inline]
bcm_tx_start_timer+0x11d/0x1b0 net/can/bcm.c:361
bcm_tx_timeout_tsklet+0x1ab/0x4b0 net/can/bcm.c:392
tasklet_action_common.isra.19+0x26f/0x720 kernel/softirq.c:522
tasklet_action+0x1d/0x20 kernel/softirq.c:540
__do_softirq+0x2e8/0xb17 kernel/softirq.c:292
run_ksoftirqd+0x86/0x100 kernel/softirq.c:653
smpboot_thread_fn+0x417/0x870 kernel/smpboot.c:164
kthread+0x345/0x410 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
other info that might help us debug this:
Chain exists of:
(console_sem).lock --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(hrtimer_bases.lock);
lock(&rt_b->rt_runtime_lock);
lock(hrtimer_bases.lock);
lock((console_sem).lock);
*** DEADLOCK ***
1 lock held by ksoftirqd/1/18:
#0: 0000000018a38b75 (hrtimer_bases.lock){-.-.}, at:
lock_hrtimer_base.isra.18+0x75/0x130 kernel/time/hrtimer.c:174
stack backtrace:
CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.18.0-rc7+ #170
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
print_circular_bug.isra.36.cold.57+0x1bd/0x27d
kernel/locking/lockdep.c:1227
check_prev_add kernel/locking/lockdep.c:1867 [inline]
check_prevs_add kernel/locking/lockdep.c:1980 [inline]
validate_chain kernel/locking/lockdep.c:2421 [inline]
__lock_acquire+0x3449/0x5020 kernel/locking/lockdep.c:3435
lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x96/0xc0 kernel/locking/spinlock.c:152
down_trylock+0x13/0x70 kernel/locking/semaphore.c:136
__down_trylock_console_sem+0xae/0x200 kernel/printk/printk.c:225
console_trylock+0x15/0xa0 kernel/printk/printk.c:2230
console_trylock_spinning kernel/printk/printk.c:1643 [inline]
vprintk_emit+0x6ad/0xdf0 kernel/printk/printk.c:1906
vprintk_default+0x28/0x30 kernel/printk/printk.c:1948
vprintk_func+0x7a/0xe7 kernel/printk/printk_safe.c:382
printk+0xa7/0xcf kernel/printk/printk.c:1981
__warn_printk+0x8c/0xe0 kernel/panic.c:590
debug_print_object+0x16a/0x210 lib/debugobjects.c:326
debug_object_activate+0x359/0x690 lib/debugobjects.c:513
debug_hrtimer_activate kernel/time/hrtimer.c:416 [inline]
debug_activate kernel/time/hrtimer.c:465 [inline]
enqueue_hrtimer+0x9e/0x540 kernel/time/hrtimer.c:954
__hrtimer_start_range_ns kernel/time/hrtimer.c:1089 [inline]
hrtimer_start_range_ns+0x616/0xd20 kernel/time/hrtimer.c:1115
hrtimer_start include/linux/hrtimer.h:398 [inline]
bcm_tx_start_timer+0x11d/0x1b0 net/can/bcm.c:361
bcm_tx_timeout_tsklet+0x1ab/0x4b0 net/can/bcm.c:392
tasklet_action_common.isra.19+0x26f/0x720 kernel/softirq.c:522
tasklet_action+0x1d/0x20 kernel/softirq.c:540
__do_softirq+0x2e8/0xb17 kernel/softirq.c:292
run_ksoftirqd+0x86/0x100 kernel/softirq.c:653
smpboot_thread_fn+0x417/0x870 kernel/smpboot.c:164
kthread+0x345/0x410 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
Shutting down cpus with NMI
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..
---
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