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.4:27782 blocked for more than 140 seconds. Not tainted 4.14.180-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28640 27782 6380 0x00000004 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x946/0xe40 kernel/time/timer.c:1723 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0x241/0x390 kernel/sched/completion.c:144 flush_work+0x3f5/0x780 kernel/workqueue.c:2893 __cancel_work_timer+0x2d0/0x460 kernel/workqueue.c:2964 p9_conn_destroy net/9p/trans_fd.c:873 [inline] p9_fd_close+0x299/0x420 net/9p/trans_fd.c:899 p9_client_destroy+0x6b/0x570 net/9p/client.c:1115 v9fs_session_init+0xe52/0x1620 fs/9p/v9fs.c:495 v9fs_mount+0x79/0x850 fs/9p/vfs_super.c:135 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x3c9/0x24f0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45ca29 RSP: 002b:00007f10ffadec78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004f62c0 RCX: 000000000045ca29 RDX: 0000000020000240 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 000000000078c0e0 R08: 0000000020000300 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000752 R14: 00000000004ca315 R15: 00007f10ffadf6d4 Showing all locks held in the system: 1 lock held by khungtaskd/1057: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 2 locks held by agetty/6267: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e4/0x16f0 drivers/tty/n_tty.c:2156 2 locks held by agetty/6269: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e4/0x16f0 drivers/tty/n_tty.c:2156 2 locks held by kworker/0:3/7300: #0: ("events"){+.+.}, at: [] work_static include/linux/workqueue.h:199 [inline] #0: ("events"){+.+.}, at: [] set_work_data kernel/workqueue.c:619 [inline] #0: ("events"){+.+.}, at: [] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ("events"){+.+.}, at: [] process_one_work+0x727/0x1540 kernel/workqueue.c:2087 #1: ((&m->wq)){+.+.}, at: [] process_one_work+0x761/0x1540 kernel/workqueue.c:2091 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 4.14.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x13e/0x194 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x139/0x17e lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5e2/0xb80 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3637 Comm: systemd-journal Not tainted 4.14.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888093c3e680 task.stack: ffff888093c40000 RIP: 0010:in_irqentry_text mm/kasan/kasan.c:418 [inline] RIP: 0010:filter_irq_stacks mm/kasan/kasan.c:430 [inline] RIP: 0010:save_stack+0x59/0xa0 mm/kasan/kasan.c:448 RSP: 0018:ffff888093c47a40 EFLAGS: 00000087 RAX: 0000000000000009 RBX: ffff88809fa55680 RCX: ffffffff818ea8fa RDX: 0000000000000004 RSI: ffff888093c47a58 RDI: 0000000000000086 RBP: 0000000001000000 R08: 0000000000000001 R09: 0000000000000000 R10: ffff888093c3ef08 R11: ffff888093c3e680 R12: ffff8880aa587e40 R13: ffff88809fa54680 R14: ffff88809fa54680 R15: ffff888093c47ea8 FS: 00007ff456bbe8c0(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff453ce6000 CR3: 00000000942b6000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kmem_cache_free+0x7c/0x2b0 mm/slab.c:3758 putname+0xcd/0x110 fs/namei.c:259 filename_lookup+0x23a/0x380 fs/namei.c:2386 user_path_at include/linux/namei.h:57 [inline] SYSC_faccessat fs/open.c:403 [inline] SyS_faccessat fs/open.c:353 [inline] SYSC_access fs/open.c:450 [inline] SyS_access+0x21a/0x680 fs/open.c:448 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7ff455e7a9c7 RSP: 002b:00007ffc85b348e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffc85b37910 RCX: 00007ff455e7a9c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055ec834839a3 RBP: 00007ffc85b34a30 R08: 000055ec834793e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 000055ec84b458c0 R15: 00007ffc85b34f20 Code: 7e 5a 9e ff 8b 04 24 85 c0 74 46 48 8b 74 24 08 31 d2 48 63 ca 48 8b 0c ce 48 81 f9 30 1a 60 86 72 09 48 81 f9 b5 61 60 86 72 12 <48> 81 f9 00 00 80 86 72 30 48 81 f9 bf 09 80 86 73 27 8d 42 01