INFO: task syz.1.182:7159 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.182 state:D stack:28704 pid:7159 tgid:7145 ppid:5814 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7286 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] lock_rename fs/namei.c:3756 [inline] __start_renaming+0x148/0x410 fs/namei.c:3852 filename_renameat2+0x38c/0x9c0 fs/namei.c:6119 __do_sys_rename fs/namei.c:6188 [inline] __se_sys_rename+0x55/0x2c0 fs/namei.c:6184 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: 0033:0x7f03b20fc799 RSP: 002b:00007f03afee9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 RAX: ffffffffffffffda RBX: 00007f03b2376270 RCX: 00007f03b20fc799 RDX: 0000000000000000 RSI: 00002000000009c0 RDI: 0000200000000a00 RBP: 00007f03b2192bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f03b2376308 R14: 00007f03b2376270 R15: 00007ffc62087468 INFO: task syz.1.182:7161 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.182 state:D stack:28800 pid:7161 tgid:7145 ppid:5814 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1553/0x5240 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7286 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_mkdirat fs/namei.c:5287 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5284 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: 0033:0x7f03b20fb607 RSP: 002b:00007f03afac5e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f03afac5ee0 RCX: 00007f03b20fb607 RDX: 00000000000001ff RSI: 0000200000000040 RDI: 00000000ffffff9c RBP: 0000200000000140 R08: 00002000000000c0 R09: 0000000000000000 R10: 0000200000000140 R11: 0000000000000246 R12: 0000200000000040 R13: 00007f03afac5ea0 R14: 0000000000000000 R15: 0000000000000000 [ 357.699109][ T38] Showing all locks held in the system: 2 locks held by kworker/u8:0/12: 3 locks held by pr/legacy/17: 1 lock held by khungtaskd/38: #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 5 locks held by kworker/u8:9/1221: #0: ffff88801aed9138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff88801aed9138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc90005cafc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc90005cafc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffffffff8f14bb80 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:675 #3: ffff888035fb70d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline] #3: ffff888035fb70d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff888035fb70d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x117/0x3f0 net/devlink/core.c:504 #4: ffff888066788300 (&devlink->lock_key#9){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:274 [inline] #4: ffff888066788300 (&devlink->lock_key#9){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff888066788300 (&devlink->lock_key#9){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x3f0 net/devlink/core.c:504 3 locks held by kworker/u8:13/1503: #0: ffff8880285a1138 ((wq_completion)loop6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline] #0: ffff8880285a1138 ((wq_completion)loop6){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358 #1: ffffc9000652fc40 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline] #1: ffffc9000652fc40 ((work_completion)(&lo->rootcg_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358 #2: ffff888025723160 (&lo->lo_work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:96 [inline] #2: ffff888025723160 (&lo->lo_work_lock){+.+.}-{3:3}, at: loop_process_work+0x125/0x11b0 drivers/block/loop.c:1953 1 lock held by klogd/5152: 1 lock held by udevd/5163: 2 locks held by getty/5560: #0: ffff888032c0c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211 9 locks held by syz-executor/5809: 4 locks held by syz.1.182/7158: 2 locks held by syz.1.182/7159: #0: ffff88802077c480 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff888062dc63b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888062dc63b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3756 [inline] #1: ffff888062dc63b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_renaming+0x148/0x410 fs/namei.c:3852 2 locks held by syz.1.182/7161: #0: ffff88802077c480 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff888062dc63b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline] #1: ffff888062dc63b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline] #1: ffff888062dc63b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline] #1: ffff888062dc63b0 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4922 9 locks held by syz-executor/7419: 3 locks held by syz-executor/8783: 5 locks held by udevd/8787: 4 locks held by syz.7.468/8850: ============================================= NMI backtrace for cpu 1 CPU: 1 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:467 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7158 Comm: syz.1.182 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:118 [inline] RIP: 0010:lock_acquire+0x80/0x2e0 kernel/locking/lockdep.c:5844 Code: 00 84 c0 0f 84 bc 01 00 00 83 3d 6a 36 ca 0d 00 0f 84 c3 00 00 00 48 8b 74 24 68 4c 89 ef e8 97 25 8a 00 83 3d 50 36 ca 0d 00 <0f> 84 c1 00 00 00 65 8b 05 13 37 ae 10 85 c0 0f 85 b2 00 00 00 65 RSP: 0018:ffffc9000621ecc0 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000297 RCX: 0000000080000002 RDX: 0000000000000000 RSI: ffffffff8b2574b0 RDI: 1ffff11017108062 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1ed4657 R12: 0000000000000000 R13: ffff8880b8840310 R14: 0000000000000000 R15: 0000000000000001 FS: 00007f03b030c6c0(0000) GS:ffff888126340000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdd5b65b000 CR3: 000000001eb84000 CR4: 00000000003526f0 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162 rt_mutex_slowtrylock kernel/locking/rtmutex.c:1391 [inline] __rt_spin_trylock kernel/locking/spinlock_rt.c:106 [inline] rt_spin_trylock+0x56/0x2b0 kernel/locking/spinlock_rt.c:118 alloc_from_pcs mm/slub.c:4689 [inline] slab_alloc_node mm/slub.c:4829 [inline] __do_kmalloc_node mm/slub.c:5237 [inline] __kmalloc_noprof+0x1fd/0x7b0 mm/slub.c:5250 kmalloc_noprof include/linux/slab.h:954 [inline] qtree_write_dquot+0x100/0x5e0 fs/quota/quota_tree.c:444 v2_write_dquot+0x183/0x260 fs/quota/quota_v2.c:372 dquot_commit+0x377/0x450 fs/quota/dquot.c:515 ext4_write_dquot+0x20a/0x380 fs/ext4/super.c:6977 mark_dquot_dirty fs/quota/dquot.c:373 [inline] mark_all_dquot_dirty+0x101/0x460 fs/quota/dquot.c:413 __dquot_free_space+0x80b/0xc00 fs/quota/dquot.c:1931 dquot_free_space_nodirty include/linux/quotaops.h:374 [inline] dquot_free_space include/linux/quotaops.h:379 [inline] dquot_free_block include/linux/quotaops.h:390 [inline] ext4_xattr_block_set+0x1487/0x2ad0 fs/ext4/xattr.c:2083 ext4_xattr_set_handle+0xe34/0x14c0 fs/ext4/xattr.c:2457 ext4_initxattrs+0x9f/0x110 fs/ext4/xattr_security.c:44 security_inode_init_security+0x296/0x3d0 security/security.c:1344 __ext4_new_inode+0x332f/0x3d20 fs/ext4/ialloc.c:1324 ext4_create+0x233/0x470 fs/ext4/namei.c:2820 lookup_open fs/namei.c:4483 [inline] open_last_lookups fs/namei.c:4583 [inline] path_openat+0x13b4/0x38a0 fs/namei.c:4827 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: 0033:0x7f03b20fc799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f03b030c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f03b2376180 RCX: 00007f03b20fc799 RDX: 0000000000000042 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f03b2192bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f03b2376218 R14: 00007f03b2376180 R15: 00007ffc62087468