INFO: task syz-executor.2:3808 blocked for more than 140 seconds. Not tainted 4.19.193-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29952 3808 8103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 request_wait_answer+0x3dc/0x750 fs/fuse/dev.c:485 __fuse_request_send+0x123/0x1c0 fs/fuse/dev.c:505 fuse_simple_request+0x2e6/0x820 fs/fuse/dev.c:576 fuse_listxattr+0x234/0x4e0 fs/fuse/xattr.c:139 vfs_listxattr+0x105/0x190 fs/xattr.c:392 listxattr+0xd3/0x140 fs/xattr.c:687 path_listxattr+0xae/0x140 fs/xattr.c:711 EXT4-fs (loop5): mounted filesystem without journal. Opts: ,errors=continue do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2e34fdd188 EFLAGS: 00000246 ORIG_RAX: 00000000000000c3 RAX: ffffffffffffffda RBX: 000000000056c0f0 RCX: 00000000004665d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0f0 R13: 00007fffcdd991df R14: 00007f2e34fdd300 R15: 0000000000022000 INFO: task syz-executor.2:3937 blocked for more than 140 seconds. Not tainted 4.19.193-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29792 3937 8103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 request_wait_answer+0x3dc/0x750 fs/fuse/dev.c:485 __fuse_request_send+0x123/0x1c0 fs/fuse/dev.c:505 fuse_simple_request+0x2e6/0x820 fs/fuse/dev.c:576 fuse_listxattr+0x234/0x4e0 fs/fuse/xattr.c:139 vfs_listxattr+0x105/0x190 fs/xattr.c:392 listxattr+0xd3/0x140 fs/xattr.c:687 path_listxattr+0xae/0x140 fs/xattr.c:711 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665d9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2e3501f188 EFLAGS: 00000246 ORIG_RAX: 00000000000000c3 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fffcdd991df R14: 00007f2e3501f300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1569: #0: 000000000d728ab6 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7796: #0: 00000000082f0f6d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by agetty/8020: #0: 00000000c6f8f5fe (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 0000000059bb6cf1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1950 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1569 Comm: khungtaskd Not tainted 4.19.193-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/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 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+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 54 Comm: kworker/u4:2 Not tainted 4.19.193-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:trace_softirqs_off+0x1e3/0x340 kernel/locking/lockdep.c:2984 Code: 00 00 00 00 00 fc ff df 89 ab 30 08 00 00 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 18 01 00 00 8b 15 43 9b d8 0b 89 ab 68 08 00 00 <85> d2 75 0c 65 8b 05 e2 82 b6 7e f6 c4 ff 74 5d 5b 5d 41 5c c3 e8 RSP: 0018:ffff8880b51a7bf0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8880b5146040 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffff8880b51468a8 RBP: 00000000024b1568 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000004 R11: 0000000000000000 R12: ffff8880b5146040 R13: ffffffff87d7d520 R14: 000000000000002a R15: ffff88803ee06400 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3311a20fc0 CR3: 0000000009e6d000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __local_bh_disable_ip+0xf0/0x190 kernel/softirq.c:129 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:134 [inline] _raw_spin_lock_bh+0x13/0x40 kernel/locking/spinlock.c:168 spin_lock_bh include/linux/spinlock.h:334 [inline] batadv_nc_purge_paths+0xdc/0x310 net/batman-adv/network-coding.c:453 batadv_nc_worker+0x6fa/0xd50 net/batman-adv/network-coding.c:731 process_one_work+0x864/0x1570 kernel/workqueue.c:2152 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415