INFO: task syz.0.2397:14930 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00067-g76b6905c11fd #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2397 state:D stack:23736 pid:14930 tgid:14926 ppid:5819 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:912 [inline] filename_create+0x260/0x540 fs/namei.c:4082 do_mknodat+0x18b/0x5b0 fs/namei.c:4228 __do_sys_mknodat fs/namei.c:4269 [inline] __se_sys_mknodat fs/namei.c:4266 [inline] __x64_sys_mknodat+0xa7/0xc0 fs/namei.c:4266 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe81d78d169 RSP: 002b:00007fe81e604038 EFLAGS: 00000246 ORIG_RAX: 0000000000000103 RAX: ffffffffffffffda RBX: 00007fe81d9a6080 RCX: 00007fe81d78d169 RDX: 00000000000081c0 RSI: 00004000000000c0 RDI: ffffffffffffff9c RBP: 00007fe81d80e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe81d9a6080 R15: 00007ffde6806b58 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 2 locks held by getty/5579: #0: ffff8880356da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fd62f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 2 locks held by syz.0.2397/14929: #0: ffff88807a77e420 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:547 #1: ffff8880793c3b38 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline] #1: ffff8880793c3b38 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: chmod_common+0x1bb/0x4c0 fs/open.c:638 2 locks held by syz.0.2397/14930: #0: ffff88807a77e420 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:547 #1: ffff8880793c3b38 (&type->i_mutex_dir_key#9/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:912 [inline] #1: ffff8880793c3b38 (&type->i_mutex_dir_key#9/1){+.+.}-{4:4}, at: filename_create+0x260/0x540 fs/namei.c:4082 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00067-g76b6905c11fd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5945 Comm: kworker/u8:9 Not tainted 6.14.0-rc7-syzkaller-00067-g76b6905c11fd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_acquire+0x287/0x550 kernel/locking/lockdep.c:5855 Code: 44 24 40 0e 36 e0 45 4b c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 11 00 00 00 00 66 43 c7 44 25 15 00 00 <43> c6 44 25 17 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 00 01 00 RSP: 0018:ffffc90004847940 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000908f34 RCX: ffff888027fb28e8 RDX: dffffc0000000000 RSI: ffffffff8c2ac600 RDI: ffffffff8c802ce0 RBP: ffffc90004847aa0 R08: ffffffff94517847 R09: 1ffffffff28a2f08 R10: dffffc0000000000 R11: fffffbfff28a2f09 R12: 1ffff92000908f30 R13: dffffc0000000000 R14: ffffc900048479a0 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056229da33970 CR3: 000000000e938000 CR4: 00000000003526f0 DR0: 0000000000000006 DR1: 0000000000000004 DR2: 000000000000002f DR3: 0000000000000008 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244