INFO: task syz.3.167:7091 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.167 state:D stack:24568 pid:7091 tgid:7090 ppid:5799 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 d_wait_lookup fs/dcache.c:2581 [inline] d_alloc_parallel+0xc3a/0x1610 fs/dcache.c:2671 __lookup_slow+0x11c/0x3d0 fs/namei.c:1843 lookup_slow+0x53/0x70 fs/namei.c:1875 walk_component fs/namei.c:2221 [inline] link_path_walk+0xd1e/0x18d0 fs/namei.c:2589 path_lookupat+0xe4/0x8c0 fs/namei.c:2745 filename_lookup+0x212/0x570 fs/namei.c:2775 user_path_at+0x3a/0x60 fs/namei.c:3567 do_mount fs/namespace.c:4032 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x2d4/0x410 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe430e7f749 RSP: 002b:00007fe42f0e6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fe4310d5fa0 RCX: 00007fe430e7f749 RDX: 0000000000000000 RSI: 0000200000000080 RDI: 0000000000000000 RBP: 00007fe430f03f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000040024 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe4310d6038 R14: 00007fe4310d5fa0 R15: 00007ffde4fac618 INFO: task syz.3.167:7140 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.167 state:D stack:26736 pid:7140 tgid:7090 ppid:5799 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 io_schedule+0x81/0xe0 kernel/sched/core.c:7789 folio_wait_bit_common+0x6b5/0xb90 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1159 [inline] release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:870 discard_metapage fs/jfs/jfs_metapage.h:88 [inline] __get_metapage+0x9a3/0xde0 fs/jfs/jfs_metapage.c:753 dtSearch+0x591/0x21b0 fs/jfs/jfs_dtree.c:624 jfs_lookup+0x155/0x380 fs/jfs/namei.c:1461 __lookup_slow+0x29d/0x3d0 fs/namei.c:1858 lookup_slow+0x53/0x70 fs/namei.c:1875 walk_component fs/namei.c:2221 [inline] lookup_last fs/namei.c:2722 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2746 filename_lookup+0x212/0x570 fs/namei.c:2775 user_path_at+0x3a/0x60 fs/namei.c:3567 do_mount fs/namespace.c:4032 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x2d4/0x410 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe430e7f749 RSP: 002b:00007fe42f0c5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fe4310d6090 RCX: 00007fe430e7f749 RDX: 0000200000000040 RSI: 0000200000000000 RDI: 0000000000000000 RBP: 00007fe430f03f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe4310d6128 R14: 00007fe4310d6090 R15: 00007ffde4fac618 INFO: task syz.3.167:7157 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.167 state:D stack:26840 pid:7157 tgid:7090 ppid:5799 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rwbase_write_lock+0x3dd/0x750 kernel/locking/rwbase_rt.c:272 inode_lock include/linux/fs.h:1027 [inline] open_last_lookups fs/namei.c:4537 [inline] path_openat+0xb53/0x3df0 fs/namei.c:4784 do_filp_open+0x1fa/0x410 fs/namei.c:4814 do_sys_openat2+0x121/0x200 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe430e7f749 RSP: 002b:00007fe42f0a4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe4310d6180 RCX: 00007fe430e7f749 RDX: 0000000000105042 RSI: 0000200000000180 RDI: ffffffffffffff9c RBP: 00007fe430f03f91 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000000001c3 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe4310d6218 R14: 00007fe4310d6180 R15: 00007ffde4fac618 INFO: task syz.3.167:7166 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.167 state:D stack:28952 pid:7166 tgid:7090 ppid:5799 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x1480/0x50a0 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241 rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline] __rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline] __rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760 __rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114 rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline] __down_read kernel/locking/rwsem.c:1466 [inline] down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539 inode_lock_shared include/linux/fs.h:1042 [inline] lookup_slow+0x46/0x70 fs/namei.c:1874 walk_component fs/namei.c:2221 [inline] lookup_last fs/namei.c:2722 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2746 filename_lookup+0x212/0x570 fs/namei.c:2775 user_path_at+0x3a/0x60 fs/namei.c:3567 do_sys_truncate+0xa3/0x190 fs/open.c:139 __do_sys_truncate fs/open.c:153 [inline] __se_sys_truncate fs/open.c:151 [inline] __x64_sys_truncate+0x5b/0x70 fs/open.c:151 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe430e7f749 RSP: 002b:00007fe42e43b038 EFLAGS: 00000246 ORIG_RAX: 000000000000004c RAX: ffffffffffffffda RBX: 00007fe4310d6450 RCX: 00007fe430e7f749 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 00002000000005c0 RBP: 00007fe430f03f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe4310d64e8 R14: 00007fe4310d6450 R15: 00007ffde4fac618 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5ae880 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5556: #0: ffff88814ea130a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:18/6238: #0: ffff888141ec1138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888141ec1138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000c10fb80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000c10fb80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 #2: ffff88802835e0d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 1 lock held by syz.3.167/7091: #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1874 1 lock held by syz.3.167/7140: #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1874 1 lock held by syz.3.167/7157: #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: path_openat+0xb53/0x3df0 fs/namei.c:4784 1 lock held by syz.3.167/7166: #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] #0: ffff88805f535d78 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1874 2 locks held by syz.4.249/7789: #0: ffff88802835e0d0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88802835e0d0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 #1: ffff888027ad2950 (&(log)->loglock){+.+.}-{4:4}, at: jfs_syncpt+0x25/0x90 fs/jfs/jfs_logmgr.c:1039 1 lock held by udevd/8079: 2 locks held by kworker/u8:25/8474: #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340 #1: ffffc9000585fb80 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000585fb80 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340 3 locks held by udevd/8530: 4 locks held by syz.9.343/8892: 6 locks held by syz.1.344/8901: 4 locks held by syz.6.346/8925: 3 locks held by syz.7.350/8927: ============================================= 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 10/25/2025 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:160 [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+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 8530 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:unwind_next_frame+0x171c/0x2390 arch/x86/kernel/unwind_orc.c:-1 Code: 8d 0b 01 0f 85 18 02 00 00 80 3d 6e cb 43 10 00 0f 85 0b 02 00 00 c6 05 61 cb 43 10 01 4c 89 f7 e8 89 0c 00 00 e9 f7 01 00 00 <48> 8b 54 24 08 48 8d 5a 02 48 83 c2 03 48 89 d8 48 c1 e8 03 0f b6 RSP: 0018:ffffc9000557f058 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc9000557f1c0 RCX: 0000000000000000 RDX: ffffffff8f6706a2 RSI: 0000000000000001 RDI: ffffc9000557f1e8 RBP: dffffc0000000000 R08: ffffc9000557f1e7 R09: 0000000000000000 R10: ffffc9000557f1d8 R11: fffff52000aafe3d R12: ffffc9000557f188 R13: ffffc9000557f1d8 R14: ffffc9000557f188 R15: 1ffffffff1ece0d4 FS: 00007fd32f4f5880(0000) GS:ffff888126e03000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2fbed0c000 CR3: 000000005d4ec000 CR4: 00000000003526f0 Call Trace: __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:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_lru_noprof+0x193/0x6c0 mm/slub.c:5282 __d_alloc+0x37/0x6f0 fs/dcache.c:1730 d_alloc_parallel+0xe1/0x1610 fs/dcache.c:2594 __lookup_slow+0x11c/0x3d0 fs/namei.c:1843 lookup_slow+0x53/0x70 fs/namei.c:1875 walk_component fs/namei.c:2221 [inline] lookup_last fs/namei.c:2722 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2746 filename_lookup+0x212/0x570 fs/namei.c:2775 vfs_statx+0xf8/0x550 fs/stat.c:353 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/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd32f64db0a 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:00007ffe6c48cd38 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 000000000000002d RCX: 00007fd32f64db0a RDX: 00007ffe6c48cd40 RSI: 00007ffe6c48ce10 RDI: 00000000ffffff9c RBP: 00007ffe6c48de50 R08: 00007ffe6c48ea80 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe6c48ea80 R13: 0000000000000000 R14: 00007ffe6c48e680 R15: 00007ffe6c48e280