INFO: task syz-executor0:8028 blocked for more than 140 seconds. Not tainted 5.0.0-rc2+ #30 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D19656 8028 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3472 schedule+0xfe/0x350 kernel/sched/core.c:3516 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xa3b/0x1670 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 msdos_lookup+0xe4/0x340 fs/fat/namei_msdos.c:208 __lookup_slow+0x2cd/0x560 fs/namei.c:1671 lookup_slow+0x58/0x80 fs/namei.c:1688 walk_component+0x8e5/0x26a0 fs/namei.c:1810 link_path_walk.part.0+0xa57/0x1550 fs/namei.c:2141 link_path_walk fs/namei.c:2072 [inline] path_openat+0x222/0x5650 fs/namei.c:3533 do_filp_open+0x26f/0x370 fs/namei.c:3564 do_sys_open+0x59a/0x7c0 fs/open.c:1063 __do_sys_open fs/open.c:1081 [inline] __se_sys_open fs/open.c:1076 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1076 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4560c0 Code: Bad RIP value. RSP: 002b:00007ffecf0ed630 EFLAGS: 00000206 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004560c0 RDX: 0000000000000000 RSI: 0000000000090800 RDI: 00000000004bcbd6 RBP: 0000000000000210 R08: 0000000000000001 R09: 000000000194d940 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000001 R13: 0000000000055ec3 R14: 000000000000009a R15: 0000000000000000 INFO: task syz-executor0:12802 blocked for more than 140 seconds. Not tainted 5.0.0-rc2+ #30 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D26488 12802 8028 0x00000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x897/0x1e60 kernel/sched/core.c:3472 schedule+0xfe/0x350 kernel/sched/core.c:3516 d_wait_lookup fs/dcache.c:2408 [inline] d_alloc_parallel+0x143c/0x1f10 fs/dcache.c:2490 __lookup_slow+0x1fa/0x560 fs/namei.c:1654 lookup_slow+0x58/0x80 fs/namei.c:1688 walk_component+0x8e5/0x26a0 fs/namei.c:1810 lookup_last fs/namei.c:2273 [inline] path_lookupat.isra.0+0x1f5/0xba0 fs/namei.c:2318 do_o_path fs/namei.c:3508 [inline] path_openat+0x2cdc/0x5650 fs/namei.c:3530 do_filp_open+0x26f/0x370 fs/namei.c:3564 do_sys_open+0x59a/0x7c0 fs/open.c:1063 __do_sys_openat fs/open.c:1090 [inline] __se_sys_openat fs/open.c:1084 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1084 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458099 Code: Bad RIP value. RSP: 002b:00007f5a199e7c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458099 RDX: 0000000000200002 RSI: 00000000200003c0 RDI: ffffffffffffff9c RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5a199e86d4 R13: 00000000004c40a0 R14: 00000000004d72b8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1040: #0: 00000000f3ac8e8a (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4389 2 locks held by getty/7992: #0: 000000004c867483 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002d6a9e96 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7993: #0: 00000000dcbb5eec (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000009520994 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7994: #0: 0000000008d397b1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008a4b627f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7995: #0: 0000000093708f0b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000007b02f696 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7996: #0: 00000000d68a3deb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000fff6c964 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7997: #0: 00000000634800ac (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a9e28952 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7998: #0: 00000000faa1929b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b824971c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by syz-executor0/8028: #0: 00000000e9e9e2c0 (&sb->s_type->i_mutex_key#23){++++}, at: inode_lock_shared include/linux/fs.h:767 [inline] #0: 00000000e9e9e2c0 (&sb->s_type->i_mutex_key#23){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1687 #1: 00000000cf18fddc (&sbi->s_lock){+.+.}, at: msdos_lookup+0xe4/0x340 fs/fat/namei_msdos.c:208 2 locks held by syz-executor0/12760: 1 lock held by syz-executor0/12802: #0: 00000000e9e9e2c0 (&sb->s_type->i_mutex_key#23){++++}, at: inode_lock_shared include/linux/fs.h:767 [inline] #0: 00000000e9e9e2c0 (&sb->s_type->i_mutex_key#23){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1687 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1040 Comm: khungtaskd Not tainted 5.0.0-rc2+ #30 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+0x1db/0x2d0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0xbbb/0x1170 kernel/hung_task.c:287 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.0.0-rc2+ #30 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:iterate_chain_key kernel/locking/lockdep.c:319 [inline] RIP: 0010:__lock_acquire+0x6c2/0x4a30 kernel/locking/lockdep.c:3333 Code: 01 dd c1 c0 10 44 89 ea 41 31 c7 44 89 f8 44 29 fb 45 01 ef c1 c8 0d 31 c3 89 d8 29 da c1 c0 04 31 d0 41 8d 14 1f 48 c1 e0 20 <48> 09 d0 48 85 ff 49 89 c7 74 2c be ff ff ff ff 44 89 5c 24 68 4c RSP: 0018:ffff8880a9467510 EFLAGS: 00000086 RAX: eebcd9c600000000 RBX: 000000002eab37d6 RCX: ffff8880a9458a40 RDX: 0000000085fe62fa RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880a94677a0 R08: 0000000000000002 R09: ffff8880a9458ab0 R10: ffff8880a9458a90 R11: 0000000000000000 R12: ffff8880a94581c0 R13: 0000000032badc7a R14: 0000000000000000 R15: 0000000057532b24 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 000000008b868000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 rcu_lock_acquire include/linux/rcupdate.h:223 [inline] rcu_read_lock include/linux/rcupdate.h:607 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:419 [inline] batadv_nc_worker+0x19b/0x920 net/batman-adv/network-coding.c:730 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352