syzbot


possible deadlock in __queue_work (3)

Status: upstream: reported on 2022/10/09 04:02
Reported-by: syzbot+4f8fc6e7d55c70fcd959@syzkaller.appspotmail.com
First crash: 59d, last: 59d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 possible deadlock in __queue_work 7 899d 1007d 0/1 auto-closed as invalid on 2020/10/15 10:06
linux-4.19 possible deadlock in __queue_work (2) 1 532d 532d 0/1 auto-closed as invalid on 2021/10/17 12:42
linux-4.19 possible deadlock in __queue_work 3 841d 936d 0/1 auto-closed as invalid on 2020/12/11 19:10
upstream possible deadlock in __queue_work (2) 16 280d 279d 0/24 closed as invalid on 2022/02/27 14:14
upstream possible deadlock in __queue_work 2 526d 585d 22/24 fixed on 2021/11/10 00:50

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.0.0-syzkaller-02734-g0326074ff465 #0 Not tainted
------------------------------------------------------
kworker/3:18/4289 is trying to acquire lock:
ffff88802c839898 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x216/0x1200 kernel/workqueue.c:1462

but task is already holding lock:
ffff888000932528 (&tty->write_wait){-.-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:136

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&tty->write_wait){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
       __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:136
       tty_port_default_wakeup+0x26/0x40 drivers/tty/tty_port.c:71
       serial8250_tx_chars+0x4f6/0xd90 drivers/tty/serial/8250/8250_port.c:1851
       serial8250_handle_irq.part.0+0x440/0x820 drivers/tty/serial/8250/8250_port.c:1938
       serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1911 [inline]
       serial8250_default_handle_irq+0xb2/0x220 drivers/tty/serial/8250/8250_port.c:1958
       serial8250_interrupt+0xf8/0x200 drivers/tty/serial/8250/8250_core.c:126
       __handle_irq_event_percpu+0x227/0x870 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0xa7/0x1e0 kernel/irq/handle.c:210
       handle_edge_irq+0x25f/0xd00 kernel/irq/chip.c:819
       generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
       handle_irq arch/x86/kernel/irq.c:231 [inline]
       __common_interrupt+0x9d/0x210 arch/x86/kernel/irq.c:250
       common_interrupt+0xa4/0xc0 arch/x86/kernel/irq.c:240
       asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:640
       native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
       arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
       default_idle+0xb/0x10 arch/x86/kernel/process.c:730
       default_idle_call+0x80/0xc0 kernel/sched/idle.c:109
       cpuidle_idle_call kernel/sched/idle.c:191 [inline]
       do_idle+0x401/0x590 kernel/sched/idle.c:303
       cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:400
       start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:262
       secondary_startup_64_no_verify+0xce/0xdb

-> #3 (&port_lock_key){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
       serial8250_console_write+0x975/0xfe0 drivers/tty/serial/8250/8250_port.c:3380
       call_console_driver kernel/printk/printk.c:1945 [inline]
       console_emit_next_record.constprop.0+0x3de/0x840 kernel/printk/printk.c:2732
       console_flush_all kernel/printk/printk.c:2794 [inline]
       console_unlock+0x37a/0x5a0 kernel/printk/printk.c:2861
       vprintk_emit+0x1b9/0x5f0 kernel/printk/printk.c:2271
       vprintk+0x80/0x90 kernel/printk/printk_safe.c:50
       _printk+0xba/0xed kernel/printk/printk.c:2292
       register_console kernel/printk/printk.c:3212 [inline]
       register_console+0x482/0x840 kernel/printk/printk.c:3104
       univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:681
       console_init+0x3b7/0x57e kernel/printk/printk.c:3308
       start_kernel+0x2fa/0x48f init/main.c:1066
       secondary_startup_64_no_verify+0xce/0xdb

-> #2 (console_owner){....}-{0:0}:
       console_lock_spinning_enable kernel/printk/printk.c:1808 [inline]
       console_emit_next_record.constprop.0+0x2dd/0x840 kernel/printk/printk.c:2729
       console_flush_all kernel/printk/printk.c:2794 [inline]
       console_unlock+0x37a/0x5a0 kernel/printk/printk.c:2861
       vprintk_emit+0x1b9/0x5f0 kernel/printk/printk.c:2271
       vprintk+0x80/0x90 kernel/printk/printk_safe.c:50
       _printk+0xba/0xed kernel/printk/printk.c:2292
       build_zonelists.cold+0xe5/0x11f mm/page_alloc.c:6471
       __build_all_zonelists+0x122/0x180 mm/page_alloc.c:6584
       build_all_zonelists_init+0x2f/0x104 mm/page_alloc.c:6609
       build_all_zonelists+0x11f/0x140 mm/page_alloc.c:6642
       start_kernel+0xb9/0x48f init/main.c:960
       secondary_startup_64_no_verify+0xce/0xdb

-> #1 (zonelist_update_seq.seqcount){...-}-{0:0}:
       seqcount_lockdep_reader_access include/linux/seqlock.h:102 [inline]
       read_seqbegin include/linux/seqlock.h:836 [inline]
       zonelist_iter_begin mm/page_alloc.c:4722 [inline]
       __alloc_pages_slowpath.constprop.0+0x1a5/0x2300 mm/page_alloc.c:5044
       __alloc_pages+0x43d/0x510 mm/page_alloc.c:5562
       __alloc_pages_node include/linux/gfp.h:243 [inline]
       kmem_getpages mm/slab.c:1363 [inline]
       cache_grow_begin+0x75/0x360 mm/slab.c:2569
       cache_alloc_refill+0x27f/0x380 mm/slab.c:2942
       ____cache_alloc mm/slab.c:3018 [inline]
       ____cache_alloc mm/slab.c:3001 [inline]
       __do_cache_alloc mm/slab.c:3246 [inline]
       slab_alloc mm/slab.c:3287 [inline]
       __kmem_cache_alloc_lru mm/slab.c:3471 [inline]
       kmem_cache_alloc+0x433/0x520 mm/slab.c:3491
       kmem_cache_zalloc include/linux/slab.h:723 [inline]
       fill_pool+0x264/0x5c0 lib/debugobjects.c:168
       __debug_object_init+0x7a/0xd10 lib/debugobjects.c:562
       debug_object_init lib/debugobjects.c:617 [inline]
       debug_object_activate+0x32c/0x3e0 lib/debugobjects.c:703
       debug_work_activate kernel/workqueue.c:510 [inline]
       __queue_work+0x614/0x1200 kernel/workqueue.c:1516
       queue_work_on+0xee/0x110 kernel/workqueue.c:1545
       queue_work include/linux/workqueue.h:503 [inline]
       schedule_work include/linux/workqueue.h:564 [inline]
       key_put.part.0+0x95/0xd0 security/keys/key.c:653
       key_put+0x1b/0x30 security/keys/key.c:649
       put_cred_rcu+0x19a/0x520 kernel/cred.c:118
       rcu_do_batch kernel/rcu/tree.c:2248 [inline]
       rcu_core+0x7b5/0x1890 kernel/rcu/tree.c:2508
       __do_softirq+0x1d0/0x9c8 kernel/softirq.c:571
       invoke_softirq kernel/softirq.c:445 [inline]
       __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
       irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
       sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1107
       asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
       jbd2_journal_write_revoke_records+0x7cc/0xb20 fs/jbd2/revoke.c:548
       jbd2_journal_commit_transaction+0x13cc/0x6a30 fs/jbd2/commit.c:587
       kjournald2+0x1d0/0x930 fs/jbd2/journal.c:210
       kthread+0x2e4/0x3a0 kernel/kthread.c:376
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

-> #0 (&pool->lock){-.-.}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3095 [inline]
       check_prevs_add kernel/locking/lockdep.c:3214 [inline]
       validate_chain kernel/locking/lockdep.c:3829 [inline]
       __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053
       lock_acquire kernel/locking/lockdep.c:5666 [inline]
       lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
       __queue_work+0x216/0x1200 kernel/workqueue.c:1462
       queue_work_on+0xee/0x110 kernel/workqueue.c:1545
       queue_work include/linux/workqueue.h:503 [inline]
       schedule_work include/linux/workqueue.h:564 [inline]
       p9_pollwake+0xbd/0x1c0 net/9p/trans_fd.c:535
       __wake_up_common+0x147/0x650 kernel/sched/wait.c:107
       __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:137
       tty_write_unlock drivers/tty/tty_io.c:945 [inline]
       do_tty_write drivers/tty/tty_io.c:1049 [inline]
       file_tty_write.constprop.0+0x54c/0x8f0 drivers/tty/tty_io.c:1095
       __kernel_write_iter+0x25e/0x730 fs/read_write.c:517
       __kernel_write fs/read_write.c:537 [inline]
       kernel_write fs/read_write.c:558 [inline]
       kernel_write+0x1bd/0x630 fs/read_write.c:548
       p9_fd_write net/9p/trans_fd.c:429 [inline]
       p9_write_work+0x25e/0xce0 net/9p/trans_fd.c:480
       process_one_work+0x991/0x1610 kernel/workqueue.c:2289
       worker_thread+0x665/0x1080 kernel/workqueue.c:2436
       kthread+0x2e4/0x3a0 kernel/kthread.c:376
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

other info that might help us debug this:

Chain exists of:
  &pool->lock --> &port_lock_key --> &tty->write_wait

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&tty->write_wait);
                               lock(&port_lock_key);
                               lock(&tty->write_wait);
  lock(&pool->lock);

 *** DEADLOCK ***

5 locks held by kworker/3:18/4289:
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc9000201fda8 ((work_completion)(&m->wq)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffff888000932098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #3: ffff888000932528 (&tty->write_wait){-.-.}-{2:2}, at: __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:136
 #4: ffffffff8bf83940 (rcu_read_lock){....}-{1:2}, at: __queue_work+0xca/0x1200 kernel/workqueue.c:1437

stack backtrace:
CPU: 3 PID: 4289 Comm: kworker/3:18 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: events p9_write_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3095 [inline]
 check_prevs_add kernel/locking/lockdep.c:3214 [inline]
 validate_chain kernel/locking/lockdep.c:3829 [inline]
 __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5053
 lock_acquire kernel/locking/lockdep.c:5666 [inline]
 lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 __queue_work+0x216/0x1200 kernel/workqueue.c:1462
 queue_work_on+0xee/0x110 kernel/workqueue.c:1545
 queue_work include/linux/workqueue.h:503 [inline]
 schedule_work include/linux/workqueue.h:564 [inline]
 p9_pollwake+0xbd/0x1c0 net/9p/trans_fd.c:535
 __wake_up_common+0x147/0x650 kernel/sched/wait.c:107
 __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:137
 tty_write_unlock drivers/tty/tty_io.c:945 [inline]
 do_tty_write drivers/tty/tty_io.c:1049 [inline]
 file_tty_write.constprop.0+0x54c/0x8f0 drivers/tty/tty_io.c:1095
 __kernel_write_iter+0x25e/0x730 fs/read_write.c:517
 __kernel_write fs/read_write.c:537 [inline]
 kernel_write fs/read_write.c:558 [inline]
 kernel_write+0x1bd/0x630 fs/read_write.c:548
 p9_fd_write net/9p/trans_fd.c:429 [inline]
 p9_write_work+0x25e/0xce0 net/9p/trans_fd.c:480
 process_one_work+0x991/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-qemu-upstream 2022/10/05 03:51 upstream 0326074ff465 267e3bb1 .config log report info possible deadlock in __queue_work
* Struck through repros no longer work on HEAD.