NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.1:28950 blocked for more than 140 seconds. Not tainted 4.19.126-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D26416 28950 6556 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x8a2/0x1fc0 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x8f3/0xed0 kernel/time/timer.c:1782 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+0x40f/0x1440 kernel/workqueue.c:2715 nbd_start_device_ioctl drivers/block/nbd.c:1262 [inline] __nbd_ioctl drivers/block/nbd.c:1333 [inline] nbd_ioctl+0x502/0xb80 drivers/block/nbd.c:1373 __blkdev_driver_ioctl block/ioctl.c:303 [inline] blkdev_ioctl+0xbf7/0x1a0a block/ioctl.c:601 block_ioctl+0xe9/0x130 fs/block_dev.c:1894 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45ca69 Code: 48 c7 44 24 10 00 00 00 00 48 8b 44 24 68 48 89 44 24 18 48 8b 44 24 70 48 89 44 24 20 48 8b 44 24 78 48 89 44 24 28 48 89 4c <24> 30 0f 57 c0 0f 11 44 24 38 48 c7 44 24 48 00 00 00 00 e8 0f d4 RSP: 002b:00007fd063e9dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e90c0 RCX: 000000000045ca69 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000409 R14: 00000000004c6ca4 R15: 00007fd063e9e6d4 Showing all locks held in the system: 2 locks held by kworker/u4:3/198: #0: 00000000f8d46913 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9688 [inline] #0: 00000000f8d46913 (&rq->lock){-.-.}, at: pick_next_task_fair+0xa59/0x1440 kernel/sched/fair.c:6840 #1: 000000002afad193 (rcu_read_lock){....}, at: cpu_of kernel/sched/sched.h:927 [inline] #1: 000000002afad193 (rcu_read_lock){....}, at: __update_idle_core+0x39/0x3e0 kernel/sched/fair.c:6057 1 lock held by khungtaskd/1080: #0: 000000002afad193 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 1 lock held by systemd-journal/3684: 2 locks held by in:imklog/6137: #0: 00000000a6615f97 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:767 #1: 00000000f8d46913 (&rq->lock){-.-.}, at: fs_reclaim_acquire.part.0+0x0/0x30 mm/page_alloc.c:2246 2 locks held by agetty/6353: #0: 000000002f9d1034 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000001fd74dfb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by kworker/u5:3/10528: #0: 000000008a08a058 ((wq_completion)"knbd%d-recv"nbd->index){+.+.}, at: process_one_work+0x78b/0x1580 kernel/workqueue.c:2126 #1: 0000000065ceefe1 ((work_completion)(&args->work)){+.+.}, at: process_one_work+0x7c1/0x1580 kernel/workqueue.c:2130 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1080 Comm: khungtaskd Not tainted 4.19.126-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+0x1fc/0x2fe lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb 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+0x962/0xe40 kernel/hung_task.c:287 kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3684 Comm: systemd-journal Not tainted 4.19.126-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_lock_release include/linux/rcupdate.h:247 [inline] RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:681 [inline] RIP: 0010:is_bpf_text_address+0xb3/0x160 kernel/bpf/core.c:547 Code: 90 f5 ff 85 db 74 19 e8 4b 8f f5 ff 0f b6 1d 08 94 14 08 31 ff 89 de e8 6b 90 f5 ff 84 db 74 2f e8 32 8f f5 ff e8 ed ab e4 ff 28 8f f5 ff 48 c7 c2 99 fb 71 81 be 01 00 00 00 48 c7 c7 60 31 RSP: 0018:ffff888094017a98 EFLAGS: 00000217 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff8171fbdd RDX: 0000000000000000 RSI: ffffffff8171fb9e RDI: ffff88809400a3b4 RBP: 00007f28fbeb29c7 R08: ffff88809400a040 R09: ffffed1015ce473b R10: ffffed1015ce473a R11: ffff8880ae7239d3 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88809400a040 R15: 0000000000000282 FS: 00007f28fcbf68c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f28f9b02000 CR3: 00000000940e7000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kernel_text_address+0x6e/0xe0 kernel/extable.c:152 __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+0x99/0x100 arch/x86/kernel/stacktrace.c:45 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc.part.0+0x4f/0xd0 mm/kasan/kasan.c:553 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc mm/slab.c:3397 [inline] kmem_cache_alloc+0x111/0x370 mm/slab.c:3557 getname_flags+0xce/0x590 fs/namei.c:140 user_path_at_empty+0x2a/0x50 fs/namei.c:2609 user_path_at include/linux/namei.h:57 [inline] do_faccessat+0x248/0x7a0 fs/open.c:397 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f28fbeb29c7 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:00007ffe1fa24ed8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffe1fa27f00 RCX: 00007f28fbeb29c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00005627ed9e79a3 RBP: 00007ffe1fa25020 R08: 00005627ed9dd3e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00005627eef048c0 R15: 00007ffe1fa25510