INFO: task syz-executor.2:24348 can't die for more than 143 seconds. task:syz-executor.2 state:D stack:26848 pid:24348 ppid: 8494 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4312 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5063 schedule+0xcf/0x270 kernel/sched/core.c:5142 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2204 do_new_mount_fc fs/namespace.c:2832 [inline] do_new_mount fs/namespace.c:2891 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3220 do_mount fs/namespace.c:3233 [inline] __do_sys_mount fs/namespace.c:3441 [inline] __se_sys_mount fs/namespace.c:3418 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3418 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007faf10ffbc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 00000000200021c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffc77722e3f R14: 00007faf10ffc9c0 R15: 000000000119bf8c INFO: task syz-executor.2:24348 blocked for more than 143 seconds. Not tainted 5.11.0-rc2-next-20210108-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:26848 pid:24348 ppid: 8494 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4312 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5063 schedule+0xcf/0x270 kernel/sched/core.c:5142 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:773 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2204 do_new_mount_fc fs/namespace.c:2832 [inline] do_new_mount fs/namespace.c:2891 [inline] path_mount+0x1678/0x1e70 fs/namespace.c:3220 do_mount fs/namespace.c:3233 [inline] __do_sys_mount fs/namespace.c:3441 [inline] __se_sys_mount fs/namespace.c:3418 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3418 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007faf10ffbc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 000000000045e219 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 000000000119bfd0 R08: 00000000200021c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffc77722e3f R14: 00007faf10ffc9c0 R15: 000000000119bf8c INFO: task syz-executor.2:24358 can't die for more than 144 seconds. task:syz-executor.2 state:R running task stack:27472 pid:24358 ppid: 8494 flags:0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1660: #0: ffffffff8b363ea0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6254 1 lock held by in:imklog/8175: #0: ffff8880256f5270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947 1 lock held by syz-executor.2/24348: #0: ffff8880309b8150 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff8880309b8150 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2204 3 locks held by syz-executor.2/24358: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1660 Comm: khungtaskd Not tainted 5.11.0-rc2-next-20210108-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:338 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 25 Comm: kworker/u4:1 Not tainted 5.11.0-rc2-next-20210108-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_is_watching+0x86/0xc0 kernel/rcu/tree.c:1119 Code: c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1f 8b 83 48 01 00 00 d1 e8 83 e0 01 65 ff 0d 2a d8 a2 7e <74> 03 5b 5d c3 e8 7f 2d a1 ff 5b 5d c3 e8 78 65 56 00 eb da e8 81 RSP: 0018:ffffc90000dffba0 EFLAGS: 00000282 RAX: 0000000000000001 RBX: ffff8880b9f35e00 RCX: ffffffff8158a161 RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8880b9f35f48 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8cefbecf R10: fffffbfff19df7d9 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000178 FS: 0000000000000000(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f426b4e4000 CR3: 00000000118ef000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_sched_held+0x1c/0x70 kernel/rcu/update.c:123 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x5b7/0x710 kernel/locking/lockdep.c:5448 rcu_lock_release include/linux/rcupdate.h:270 [inline] rcu_read_unlock include/linux/rcupdate.h:708 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x7a3/0xe50 net/batman-adv/network-coding.c:715 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296