INFO: task syz.9.4594:23741 blocked for more than 143 seconds. Not tainted 6.16.0-rc3-syzkaller-00044-g7595b66ae9de #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.4594 state:D stack:26552 pid:23741 tgid:23740 ppid:19722 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 netfs_wait_for_request+0x161/0x5a0 fs/netfs/misc.c:450 netfs_unbuffered_write_iter_locked+0x8c3/0xc80 fs/netfs/direct_write.c:110 netfs_unbuffered_write_iter+0x414/0x6d0 fs/netfs/direct_write.c:193 v9fs_file_write_iter+0xbf/0x100 fs/9p/vfs_file.c:404 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x6c7/0x1150 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6d6b58e929 RSP: 002b:00007f6d6c4c6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f6d6b7b5fa0 RCX: 00007f6d6b58e929 RDX: 0000000000000029 RSI: 0000200000000200 RDI: 0000000000000006 RBP: 00007f6d6b610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6d6b7b5fa0 R15: 00007ffcbaf152c8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 2 locks held by getty/5575: #0: ffff8880321f70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by syz.9.4594/23741: #0: ffff8880365b2d38 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2a2/0x370 fs/file.c:1217 #1: ffff8880625f2428 (sb_writers#19){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:738 #2: ffff88807d668148 (&sb->s_type->i_mutex_key#23){++++}-{4:4}, at: netfs_start_io_direct+0x116/0x260 fs/netfs/locking.c:188 6 locks held by dhcpcd-run-hook/25498: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc3-syzkaller-00044-g7595b66ae9de #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9935 Comm: kworker/u8:15 Not tainted 6.16.0-rc3-syzkaller-00044-g7595b66ae9de #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_wait_context kernel/locking/lockdep.c:4858 [inline] RIP: 0010:__lock_acquire+0x249/0x1c90 kernel/locking/lockdep.c:5190 Code: ed 4b 3b 14 0f 83 1e 05 00 00 48 8d 04 80 48 8d 04 80 48 8d 04 c5 60 a9 d3 95 44 0f b6 b0 c4 00 00 00 4c 89 ef e8 77 b0 ff ff <44> 0f b6 b8 c5 00 00 00 45 84 f6 0f 84 02 01 00 00 41 0f b6 4d 21 RSP: 0018:ffffc900049579e8 EFLAGS: 00000003 RAX: ffffffff95d3aed8 RBX: 0000000000000002 RCX: 0000000000020000 RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffff8880782a53c0 RBP: ffff8880782a4880 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000050 R11: 0000000000000001 R12: ffff8880782a5370 R13: ffff8880782a53c0 R14: 0000000000000003 R15: ffffffff8e5c4940 FS: 0000000000000000(0000) GS:ffff888124752000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a36b19e650 CR3: 000000007ddae000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000004144 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x16a/0x1030 net/batman-adv/network-coding.c:719 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245