INFO: task kworker/u4:10:12671 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. PM: Marking nosave pages: [mem 0x00000000-0x00000fff] kworker/u4:10 D26048 12671 2 0x80000000 PM: Marking nosave pages: [mem 0x0009f000-0x000fffff] Workqueue: netns cleanup_net Call Trace: PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff] context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 PM: Basic memory bitmaps created schedule_timeout+0x92d/0xfe0 kernel/time/timer.c:1794 PM: Basic memory bitmaps freed do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x29c/0x470 kernel/sched/completion.c:115 flush_workqueue+0x40b/0x13e0 kernel/workqueue.c:2713 flush_scheduled_work include/linux/workqueue.h:599 [inline] tipc_exit_net+0x38/0x60 net/tipc/core.c:100 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:554 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 00000000fcbc1c5e (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 2 locks held by kworker/u4:4/3342: #0: 0000000057c4ae64 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1826 [inline] #0: 0000000057c4ae64 (&rq->lock){-.-.}, at: __schedule+0x1f9/0x2040 kernel/sched/core.c:3455 #1: 00000000fcbc1c5e (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:428 [inline] #1: 00000000fcbc1c5e (rcu_read_lock){....}, at: update_curr+0x2c3/0x870 kernel/sched/fair.c:857 2 locks held by kworker/1:2/3533: #0: 00000000bc08ca82 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 0000000062d889d9 ((work_completion)(&m->rq)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 1 lock held by in:imklog/7773: 3 locks held by kworker/u4:10/12671: #0: 000000007e6f80ac ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000004e55c60d (net_cleanup_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 000000002645dc0d (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x8b0 net/core/net_namespace.c:521 3 locks held by kworker/u4:1/1130: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4689 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:write_comp_data+0x6/0x70 kernel/kcov.c:121 Code: 00 00 8b 80 64 13 00 00 48 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 0f 1f 84 00 00 00 00 00 49 89 f1 49 89 fa <65> 48 8b 34 25 c0 df 01 00 65 8b 05 7a 59 9f 7e a9 00 01 1f 00 75 RSP: 0018:ffff8880a13efae8 EFLAGS: 00000046 RAX: ffff8880a13e04c0 RBX: 0000000000000000 RCX: ffffffff816d1100 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 00007efd46b3e9c7 R08: 00000000594ea6fa R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000074071 R12: ffff8880a13efbf0 R13: 0000000000000000 R14: ffff8880a13efeb0 R15: 0000000000000000 FS: 00007efd478838c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efd437a0000 CR3: 00000000a1299000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock include/linux/rcupdate.h:628 [inline] is_bpf_text_address+0x60/0x1b0 kernel/bpf/core.c:546 kernel_text_address kernel/extable.c:152 [inline] kernel_text_address+0xbd/0xf0 kernel/extable.c:122 __kernel_text_address+0x9/0x30 kernel/extable.c:107 unwind_get_return_address arch/x86/kernel/unwind_orc.c:297 [inline] unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:292 __save_stack_trace+0xaf/0x190 arch/x86/kernel/stacktrace.c:45 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x126/0x1f0 mm/kasan/kasan.c:521 __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 __put_cred+0x1de/0x250 kernel/cred.c:151 put_cred include/linux/cred.h:279 [inline] do_faccessat+0x64e/0x7a0 fs/open.c:438 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7efd46b3e9c7 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:00007ffe5829dc28 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffe582a0c50 RCX: 00007efd46b3e9c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055a54bb4f9a3 RBP: 00007ffe5829dd70 R08: 000055a54bb453e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 000055a54c87f8a0 R15: 00007ffe5829e260