IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready INFO: task syz-executor2:4339 blocked for more than 140 seconds. Not tainted 4.19.0-rc2+ #226 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D22504 4339 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x87c/0x1df0 kernel/sched/core.c:3473 schedule+0xfb/0x450 kernel/sched/core.c:3517 __rwsem_down_write_failed_common+0x98b/0x1650 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xaa/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:738 [inline] vfs_unlink+0xd1/0x510 fs/namei.c:3991 do_unlinkat+0x6cc/0xa30 fs/namei.c:4063 __do_sys_unlink fs/namei.c:4110 [inline] __se_sys_unlink fs/namei.c:4108 [inline] __x64_sys_unlink+0x42/0x50 fs/namei.c:4108 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456de7 Code: 31 00 00 00 e8 fa 4a fd ff 0f 0b e8 e3 30 00 00 e9 fe fe ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff 48 3b 61 10 0f 86 ac 00 00 00 48 83 ec 28 48 89 6c 24 20 48 RSP: 002b:0000000000a3dbe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000456de7 RDX: 0000000000a3dc00 RSI: 0000000000a3dc90 RDI: 0000000000a3dc90 RBP: 00000000000003f4 R08: 0000000000000000 R09: 0000000000000013 R10: 0000000000000005 R11: 0000000000000206 R12: 0000000000a3ed80 R13: 0000000001790980 R14: 0000000000000000 R15: badc0ffeebadface Showing all locks held in the system: 1 lock held by khungtaskd/792: #0: 00000000f015d8b9 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4436 1 lock held by rsyslogd/4196: 2 locks held by getty/4286: #0: 0000000084cabb00 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000004457f38d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4287: #0: 00000000cab5a444 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000f9966f07 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4288: #0: 00000000614a9d1f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000004fb11634 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4289: #0: 000000000d32a7ac (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000063e87d1e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4290: #0: 0000000046350ecc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000afaeacd9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4291: #0: 0000000006fe63f1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000093c63c80 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4292: #0: 00000000c45cd58c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000a811da55 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 3 locks held by syz-executor2/4339: #0: 00000000fe8387fb (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 00000000fe8387fb (sb_writers#3){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 #1: 00000000e8e7f074 (&sb->s_type->i_mutex_key#11/1){+.+.}, at: inode_lock_nested include/linux/fs.h:773 [inline] #1: 00000000e8e7f074 (&sb->s_type->i_mutex_key#11/1){+.+.}, at: do_unlinkat+0x3d8/0xa30 fs/namei.c:4049 #2: 000000003686c4ee (&sb->s_type->i_mutex_key#11){++++}, at: inode_lock include/linux/fs.h:738 [inline] #2: 000000003686c4ee (&sb->s_type->i_mutex_key#11){++++}, at: vfs_unlink+0xd1/0x510 fs/namei.c:3991 2 locks held by syz-executor2/14740: #0: 00000000fe8387fb (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2758 [inline] #0: 00000000fe8387fb (sb_writers#3){.+.+}, at: vfs_write+0x42a/0x560 fs/read_write.c:548 #1: 000000003686c4ee (&sb->s_type->i_mutex_key#11){++++}, at: inode_lock include/linux/fs.h:738 [inline] #1: 000000003686c4ee (&sb->s_type->i_mutex_key#11){++++}, at: generic_file_write_iter+0xed/0x870 mm/filemap.c:3289 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 792 Comm: khungtaskd Not tainted 4.19.0-rc2+ #226 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb39/0x1040 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.0-rc2+ #226 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:reschedule_interrupt+0x0/0x20 arch/x86/entry/entry_64.S:887 Code: 66 2e 0f 1f 84 00 00 00 00 00 68 03 ff ff ff e8 56 f2 ff ff e8 d1 27 00 00 e9 4b f3 ff ff 66 90 66 2e 0f 1f 84 00 00 00 00 00 <68> 02 ff ff ff e8 36 f2 ff ff e8 d1 21 00 00 e9 2b f3 ff ff 66 90 RSP: 0018:ffff8801d9edfc08 EFLAGS: 00000082 RAX: dffffc0000000000 RBX: 1ffff1003b3dbf8a RCX: 0000000000000000 RDX: 1ffffffff10237c8 RSI: 0000000000000001 RDI: ffffffff8811be40 RBP: ffff8801d9edfc30 R08: ffff8801d9ece380 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: ffff8801d9edfcf0 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001d09f7000 CR4: 00000000001406e0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0xc2/0x420 arch/x86/kernel/process.c:498 arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:489 default_idle_call+0x6d/0x90 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x3aa/0x580 kernel/sched/idle.c:262 cpu_startup_entry+0x10c/0x120 kernel/sched/idle.c:368 start_secondary+0x433/0x5d0 arch/x86/kernel/smpboot.c:271 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242