INFO: task syz.0.19:4431 blocked for more than 143 seconds. Not tainted 6.1.138-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.19 state:D stack:29104 pid:4431 ppid:4259 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 rwsem_down_write_slowpath+0xbed/0x1090 kernel/locking/rwsem.c:1189 inode_lock_nested include/linux/fs.h:793 [inline] filename_create+0x1f2/0x450 fs/namei.c:3876 do_symlinkat+0xb9/0x3f0 fs/namei.c:4490 __do_sys_symlink fs/namei.c:4522 [inline] __se_sys_symlink fs/namei.c:4520 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4520 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fca9b58e969 RSP: 002b:00007fca9b3bd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 00007fca9b7b6160 RCX: 00007fca9b58e969 RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 00002000000005c0 RBP: 00007fca9b610ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fca9b7b6160 R15: 00007ffe9c2aa2a8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c92b2f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8c92bb10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 3 locks held by kworker/1:1/26: 1 lock held by khungtaskd/28: #0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 3 locks held by kworker/u4:2/35: 2 locks held by getty/4013: #0: ffff88814cbb5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000326b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 4 locks held by kworker/u4:8/4347: #0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #1: ffffc900040a7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a1/0x1160 kernel/workqueue.c:2267 #2: ffffffff8db27350 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:594 #3: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #3: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962 4 locks held by syz.0.19/4430: 2 locks held by syz.0.19/4431: #0: ffff888023b0e460 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:393 #1: ffff888070168f30 (&sb->s_type->i_mutex_key#22/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline] #1: ffff888070168f30 (&sb->s_type->i_mutex_key#22/1){+.+.}-{3:3}, at: filename_create+0x1f2/0x450 fs/namei.c:3876 1 lock held by syz.4.410/6035: 1 lock held by dhcpcd-run-hook/6056: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.138-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6035 Comm: syz.4.410 Not tainted 6.1.138-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_preemption_disabled+0x1f/0x110 lib/smp_processor_id.c:16 Code: bf 8a 48 c7 c6 80 0d bf 8a eb 00 55 41 57 41 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 05 c1 c3 f2 75 <65> 8b 0d 62 19 f3 75 f7 c1 ff ff ff 7f 74 1f 65 48 8b 0c 25 28 00 RSP: 0018:ffffc900035afaa0 EFLAGS: 00000086 RAX: 0000000000000000 RBX: ffff88802e589dc0 RCX: ed9dfbcd17124500 RDX: 0000000000000000 RSI: ffffffff8a6c0f80 RDI: ffffffff8abf0da0 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff520006b5ed9 R10: fffff520006b5ed9 R11: 1ffff920006b5ed8 R12: dffffc0000000000 R13: 0000000000000246 R14: ffffffff8c92aa20 R15: 00000000ffffffff FS: 00007fad2ab266c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fae04182338 CR3: 000000007952f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] lock_is_held_type+0x100/0x190 kernel/locking/lockdep.c:5706 lock_is_held include/linux/lockdep.h:283 [inline] __might_resched+0xf2/0x610 kernel/sched/core.c:9928 __might_fault+0x6d/0x120 mm/memory.c:5850 do_recvmmsg+0x382/0x7d0 net/socket.c:2880 __sys_recvmmsg net/socket.c:2953 [inline] __do_sys_recvmmsg net/socket.c:2976 [inline] __se_sys_recvmmsg net/socket.c:2969 [inline] __x64_sys_recvmmsg+0x18d/0x240 net/socket.c:2969 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fad29d8e969 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fad2ab26038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fad29fb6080 RCX: 00007fad29d8e969 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005 RBP: 00007fad29e10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fad29fb6080 R15: 00007ffc9b763ac8