INFO: task syz.6.261:8014 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.261 state:D stack:29024 pid:8014 tgid:7993 ppid:6531 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760 rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800 __rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline] rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244 inode_lock_nested include/linux/fs.h:1073 [inline] __start_dirop fs/namei.c:2923 [inline] start_dirop fs/namei.c:2934 [inline] filename_create+0x200/0x370 fs/namei.c:4922 filename_mkdirat+0xd2/0x520 fs/namei.c:5259 __do_sys_mkdir fs/namei.c:5293 [inline] __se_sys_mkdir+0x34/0x150 fs/namei.c:5290 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f75ee5bc799 RSP: 002b:00007f75ebf8e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f75ee836360 RCX: 00007f75ee5bc799 RDX: 0000000000000000 RSI: 0000000000000058 RDI: 0000200000000300 RBP: 00007f75ee652c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f75ee8363f8 R14: 00007f75ee836360 R15: 00007ffd71867c88 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5556: #0: ffff88803258a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by udevd/5936: 7 locks held by syz.6.261/8011: 2 locks held by syz.6.261/8014: #0: ffff8880607b8480 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff88803fcb2850 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff88803fcb2850 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff88803fcb2850 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff88803fcb2850 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4922 4 locks held by syz-executor/9156: 2 locks held by udevd/9165: 1 lock held by syz-executor/9362: 1 lock held by syz.3.483/9779: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 9782 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:check_wait_context kernel/locking/lockdep.c:4877 [inline] RIP: 0010:__lock_acquire+0x4ec/0x2cf0 kernel/locking/lockdep.c:5187 Code: 00 00 49 89 ed 0f 84 cc 04 00 00 41 3b 9e b0 0b 00 00 0f 8d f5 00 00 00 4c 63 fb 4b 8d 04 bf 49 8d 1c c6 48 81 c3 d8 0b 00 00 1d 44 89 e0 49 ff c7 49 63 8e b0 0b 00 00 48 83 c3 28 41 89 c4 RSP: 0018:ffffc90006e8ef38 EFLAGS: 00000082 RAX: 0000000000000000 RBX: ffff88802e56aa58 RCX: 00000000ffffffff RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88802e56aa60 R08: ffffffff81767e65 R09: ffffffff8ddcb980 R10: ffffc90006e8f218 R11: ffffffff81af88b0 R12: ffffffffffffff05 R13: ffff88802e56aa60 R14: ffff88802e569e80 R15: 0000000000000000 FS: 00007f05576a2c80(0000) GS:ffff88812643c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9501245900 CR3: 000000005e2b8000 CR4: 00000000003526f0 Call Trace: lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2685 [inline] slab_free mm/slub.c:6165 [inline] kfree+0x1c1/0x6c0 mm/slub.c:6483 tomoyo_check_open_permission+0x32c/0x470 security/tomoyo/file.c:791 security_file_open+0xa9/0x240 security/security.c:2636 do_dentry_open+0x4c0/0x13e0 fs/open.c:926 vfs_open+0x3b/0x350 fs/open.c:1081 do_open fs/namei.c:4671 [inline] path_openat+0x2e43/0x38a0 fs/namei.c:4830 do_file_open+0x23e/0x4a0 fs/namei.c:4859 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0557860c3a Code: 41 89 f2 48 89 54 24 e0 41 83 e2 40 75 2a 89 f0 f7 d0 a9 00 00 41 00 74 1f 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 77 2e c3 0f 1f 44 00 00 48 8d 44 24 08 c7 44 24 RSP: 002b:00007ffcb2977d98 EFLAGS: 00000206 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0557860c3a RDX: 0000000000090800 RSI: 000055d1447ea0a0 RDI: 00000000ffffff9c RBP: 000055d1447ea06e R08: 00007f055793cac0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffcb2977ef8 R13: 000055d1447ea068 R14: 0000000000000001 R15: 000055d1447ea0c7