INFO: task syz.2.154:7094 blocked for more than 143 seconds. Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.154 state:D stack:28904 pid:7094 tgid:7066 ppid:5844 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0x165/0x360 kernel/sched/core.c:6883 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940 rwsem_down_write_slowpath+0xbec/0x1030 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+0x1b5/0x200 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:914 [inline] do_unlinkat+0x1bf/0x560 fs/namei.c:4646 __do_sys_unlink fs/namei.c:4705 [inline] __se_sys_unlink fs/namei.c:4703 [inline] __x64_sys_unlink+0x47/0x50 fs/namei.c:4703 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a4658e929 RSP: 002b:00007f2a4744c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 00007f2a467b6080 RCX: 00007f2a4658e929 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000080 RBP: 00007f2a46610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f2a467b6080 R15: 00007fff586cf908 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 4 locks held by kworker/u8:6/1092: #0: ffff88801feec948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801feec948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90003a47bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003a47bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffff8880300080e0 (&type->s_umount_key#77){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 #3: ffff888054011438 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102 2 locks held by getty/5605: #0: ffff88803599a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036e32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5837: #0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998 1 lock held by syz-executor/5848: 2 locks held by udevd/5853: 4 locks held by syz.2.154/7070: 2 locks held by syz.2.154/7094: #0: ffff888030008428 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff8880540117e8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline] #1: ffff8880540117e8 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: do_unlinkat+0x1bf/0x560 fs/namei.c:4646 2 locks held by syz-executor/7308: #0: ffff88804d4f60e0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88804d4f60e0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88804d4f60e0 (&type->s_umount_key#61){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8e144b40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3786 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/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+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 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: 5853 Comm: udevd Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0x58/0x360 kernel/locking/lockdep.c:5834 Code: 8b 05 ec e2 fe 10 48 89 44 24 58 0f 1f 44 00 00 65 8b 05 ef e2 fe 10 83 f8 08 0f 83 b8 01 00 00 89 c0 48 0f a3 05 98 98 02 0e <73> 16 e8 41 f1 08 00 84 c0 75 0d f6 05 d3 82 ec 0d 01 0f 84 d7 01 RSP: 0018:ffffc900041672f8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e13f160 RBP: ffffffff81729ae5 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90004167518 R11: fffff5200082cea5 R12: 0000000000000002 R13: ffffffff8e13f160 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fc555dd6880(0000) GS:ffff888125c4f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc555dae000 CR3: 0000000075c7e000 CR4: 00000000003526f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x213/0x4b0 security/tomoyo/file.c:822 security_inode_getattr+0x12f/0x330 security/security.c:2377 vfs_getattr fs/stat.c:259 [inline] vfs_statx_path fs/stat.c:299 [inline] vfs_statx+0x18e/0x550 fs/stat.c:356 vfs_fstatat+0x118/0x170 fs/stat.c:375 __do_sys_newfstatat fs/stat.c:542 [inline] __se_sys_newfstatat fs/stat.c:536 [inline] __x64_sys_newfstatat+0x116/0x190 fs/stat.c:536 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc555711b0a Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7 RSP: 002b:00007ffd693cef98 EFLAGS: 00000206 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 000055d2b2ff5e20 RCX: 00007fc555711b0a RDX: 00007ffd693cefc0 RSI: 000055d2b2ff5e20 RDI: 00000000ffffff9c RBP: 000055d2b2ff5e39 R08: 00000000000005e0 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffd693d00e5 R13: 00007ffd693cf050 R14: 000055d28c0906d7 R15: 00007ffd693d00e0