INFO: task kworker/u4:15:10578 blocked for more than 143 seconds. Not tainted 5.6.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:15 D24792 10578 2 0x80004000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: schedule+0xd0/0x2a0 kernel/sched/core.c:4168 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1874 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138 __synchronize_srcu+0x1a7/0x260 kernel/rcu/srcutree.c:922 fsnotify_mark_destroy_workfn+0xfd/0x330 fs/notify/mark.c:832 process_one_work+0x965/0x16a0 kernel/workqueue.c:2266 worker_thread+0x96/0xe20 kernel/workqueue.c:2412 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/u4:19:18256 blocked for more than 143 seconds. Not tainted 5.6.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:19 D24792 18256 2 0x80004000 Workqueue: events_unbound fsnotify_connector_destroy_workfn Call Trace: schedule+0xd0/0x2a0 kernel/sched/core.c:4168 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1874 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138 __synchronize_srcu+0x1a7/0x260 kernel/rcu/srcutree.c:922 fsnotify_connector_destroy_workfn+0x49/0xa0 fs/notify/mark.c:164 process_one_work+0x965/0x16a0 kernel/workqueue.c:2266 worker_thread+0x96/0xe20 kernel/workqueue.c:2412 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task kworker/u4:23:18266 blocked for more than 144 seconds. Not tainted 5.6.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:23 D24792 18266 2 0x80004000 Workqueue: netns cleanup_net Call Trace: schedule+0xd0/0x2a0 kernel/sched/core.c:4168 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1874 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138 flush_workqueue+0x403/0x14f0 kernel/workqueue.c:2829 rxrpc_destroy_all_connections+0xf9/0x3ff net/rxrpc/conn_object.c:468 rxrpc_exit_net+0x1ac/0x2f0 net/rxrpc/net_ns.c:122 ops_exit_list.isra.0+0xa8/0x150 net/core/net_namespace.c:186 cleanup_net+0x511/0xa50 net/core/net_namespace.c:603 process_one_work+0x965/0x16a0 kernel/workqueue.c:2266 worker_thread+0x96/0xe20 kernel/workqueue.c:2412 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.1:22495 blocked for more than 144 seconds. Not tainted 5.6.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27120 22495 7242 0x00004004 Call Trace: schedule+0xd0/0x2a0 kernel/sched/core.c:4168 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1874 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138 __flush_work+0x4fd/0xa80 kernel/workqueue.c:3043 __cancel_work_timer+0x3a2/0x500 kernel/workqueue.c:3130 p9_conn_destroy net/9p/trans_fd.c:863 [inline] p9_fd_close+0x29c/0x520 net/9p/trans_fd.c:898 p9_client_create+0x99b/0x1440 net/9p/client.c:1069 v9fs_session_init+0x1e7/0x18c0 fs/9p/v9fs.c:406 v9fs_mount+0x79/0x970 fs/9p/vfs_super.c:124 legacy_get_tree+0x105/0x220 fs/fs_context.c:622 vfs_get_tree+0x89/0x2f0 fs/super.c:1547 do_new_mount fs/namespace.c:2816 [inline] do_mount+0x1306/0x1b30 fs/namespace.c:3141 __do_sys_mount fs/namespace.c:3350 [inline] __se_sys_mount fs/namespace.c:3327 [inline] __x64_sys_mount+0x18f/0x230 fs/namespace.c:3327 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45c889 Code: Bad RIP value. RSP: 002b:00007fdba367dc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fdba367e6d4 RCX: 000000000045c889 RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 000000000076bf00 R08: 0000000020000200 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000074a R14: 00000000004ca0c5 R15: 000000000076bf0c Showing all locks held in the system: 3 locks held by kworker/0:0/5: 2 locks held by kworker/u4:5/334: #0: ffff8880ae737998 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1257 [inline] #0: ffff8880ae737998 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x233/0x1ff0 kernel/sched/core.c:4040 #1: ffff8880ae722ec8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x304/0x410 kernel/sched/psi.c:817 1 lock held by khungtaskd/1139: #0: ffffffff899bc240 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5743 1 lock held by in:imklog/6759: #0: ffff8880a2968d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by agetty/6763: #0: ffff88809ddb8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000f252e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x220/0x1b30 drivers/tty/n_tty.c:2156 2 locks held by kworker/u4:15/10578: #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2237 #1: ffffc90008a47dc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2241 3 locks held by kworker/u4:16/10582: 2 locks held by kworker/u4:19/18256: #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa034138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2237 #1: ffffc90001d27dc0 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2241 3 locks held by kworker/u4:23/18266: #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880a9787138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2237 #1: ffffc9000499fdc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2241 #2: ffffffff8a56cd70 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 net/core/net_namespace.c:565 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1139 Comm: khungtaskd Not tainted 5.6.0-syzkaller #0 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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa8c/0x1010 kernel/hung_task.c:289 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4147 Comm: systemd-journal Not tainted 5.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:page_zone include/linux/mm.h:1393 [inline] RIP: 0010:__free_pages_ok+0x446/0xe90 mm/page_alloc.c:1478 Code: eb 37 41 83 e6 3c b9 3d 00 00 00 48 89 df 44 29 f1 4c 89 ea 83 e7 07 48 d3 ee 44 89 e1 48 69 ff 00 07 00 00 49 89 f0 4c 89 fe <48> 03 3c c5 60 12 89 8a 41 83 e0 07 e8 e9 f9 ff ff f7 c5 00 02 00 RSP: 0018:ffffc90001607c10 EFLAGS: 00000006 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 00000000000436f8 RSI: ffffea00010dbe00 RDI: 0000000000000700 RBP: 0000000000000086 R08: 0000002211110000 R09: ffffed10086df000 R10: ffffffff8c84ae9b R11: fffffbfff19095d3 R12: 0000000000000001 R13: 00000000000436f8 R14: 000000000000002c R15: ffffea00010dbe00 FS: 00007f865ca728c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8659f90000 CR3: 00000000a8406000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: slab_destroy+0x14/0x40 mm/slab.c:1620 slabs_destroy+0x6a/0x90 mm/slab.c:1636 cache_flusharray mm/slab.c:3413 [inline] ___cache_free+0x29f/0x3a0 mm/slab.c:3457 qlink_free mm/kasan/quarantine.c:148 [inline] qlist_free_all+0x79/0x140 mm/kasan/quarantine.c:167 quarantine_reduce+0x159/0x190 mm/kasan/quarantine.c:260 __kasan_kmalloc.constprop.0+0x97/0xd0 mm/kasan/common.c:476 slab_post_alloc_hook mm/slab.h:586 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x11b/0x740 mm/slab.c:3484 prepare_creds+0x39/0x6b0 kernel/cred.c:258 do_faccessat+0x94/0x7a0 fs/open.c:360 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x7f865bd2e9c7 Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc17c52698 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffc17c556c0 RCX: 00007f865bd2e9c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055b1e72449a3 RBP: 00007ffc17c527e0 R08: 000055b1e723a3e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 000055b1e7b658c0 R15: 00007ffc17c52cd0