INFO: task syz.0.17:6428 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:25080 pid:6428 tgid:6427 ppid:6296 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x149b/0x4fb0 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+0x6b0/0xb80 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1159 [inline] release_metapage+0x103/0xac0 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_open fs/namei.c:4413 [inline] open_last_lookups fs/namei.c:4540 [inline] path_openat+0x139a/0x3dd0 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+0x8a/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f3d8758f749 RSP: 002b:00007f3d88365038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f3d877e5fa0 RCX: 00007f3d8758f749 RDX: 0000000000040042 RSI: 0000200000000240 RDI: ffffffffffffff9c RBP: 00007f3d87613f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3d877e6038 R14: 00007f3d877e5fa0 R15: 00007fff0d43cf78 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3f980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3f980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3f980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/36: #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340 #1: ffffc90000ac7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90000ac7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340 #2: ffff88805a98e0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 3 locks held by kworker/u8:3/38: #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340 #1: ffffc90000ae7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90000ae7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340 #2: ffff88807c5f00e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 3 locks held by kworker/u8:4/60: #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340 #1: ffffc9000211fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000211fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340 #2: ffff8880255880e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 6 locks held by kworker/u8:8/1154: 3 locks held by kworker/u8:9/1304: #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340 #1: ffffc9000470fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000470fba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340 #2: ffff88814c3480e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 3 locks held by kworker/u8:12/3455: #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340 #1: ffffc9000c1e7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000c1e7ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340 #2: ffff888063b3a0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 3 locks held by kworker/u8:13/3556: #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340 #1: ffffc9000c667ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc9000c667ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340 #2: ffff8880293ac0e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 2 locks held by getty/5587: #0: ffff888033d420a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x449/0x1460 drivers/tty/n_tty.c:2211 1 lock held by syz.0.17/6428: #0: ffff88805af8b340 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805af8b340 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88805af8b340 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 1 lock held by syz.1.18/6453: #0: ffff88805af8ea30 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805af8ea30 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88805af8ea30 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 1 lock held by syz.2.19/6475: #0: ffff88807317e108 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88807317e108 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88807317e108 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 1 lock held by syz.3.20/6503: #0: ffff8880733f4590 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff8880733f4590 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff8880733f4590 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 1 lock held by syz.4.21/6531: #0: ffff88805ae420f0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805ae420f0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88805ae420f0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 1 lock held by syz.5.22/6563: #0: ffff8880733f6a30 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff8880733f6a30 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff8880733f6a30 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 3 locks held by kworker/u8:17/6564: #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff88801e2ad948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1760 kernel/workqueue.c:3340 #1: ffffc900041afba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc900041afba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1760 kernel/workqueue.c:3340 #2: ffff8880245520e0 (&type->s_umount_key#54){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563 1 lock held by syz.6.23/6597: #0: ffff88805af957e0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805af957e0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88805af957e0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 1 lock held by syz.7.24/6631: #0: ffff88805afebc68 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805afebc68 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88805afebc68 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 1 lock held by syz.8.25/6663: #0: ffff88805af90ea0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #0: ffff88805af90ea0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:4537 [inline] #0: ffff88805af90ea0 (&type->i_mutex_dir_key#9){+.+.}-{4:4}, at: path_openat+0xb47/0x3dd0 fs/namei.c:4784 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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: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+0x17e9/0x1840 kernel/hung_task.c:515 kthread+0x711/0x890 kernel/kthread.c:463 ret_from_fork+0x50c/0xa50 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: 5181 Comm: klogd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:kasan_byte_accessible+0x16/0x30 mm/kasan/generic.c:212 Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df 0f b6 04 07 <3c> 08 0f 92 c0 e9 40 35 19 09 cc 66 66 66 66 66 66 2e 0f 1f 84 00 RSP: 0018:ffffc90002f674f8 EFLAGS: 00000802 RAX: 0000000000000000 RBX: ffffffff8b3f3470 RCX: 0000000080000002 RDX: 0000000000000000 RSI: ffffffff8b3f3470 RDI: 1ffff11003404b0b RBP: ffffffff821bb2b3 R08: 0000000000000001 R09: 0000000000000000 R10: dffffc0000000000 R11: fffffbfff1efa8af R12: 0000000000000000 R13: ffff88801a025858 R14: ffff88801a025858 R15: 0000000000000001 FS: 00007f6efb463c80(0000) GS:ffff8881261ea000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c5d914fe30 CR3: 0000000030610000 CR4: 00000000003526f0 Call Trace: __kasan_check_byte+0x12/0x40 mm/kasan/common.c:572 kasan_check_byte include/linux/kasan.h:401 [inline] lock_acquire+0x84/0x330 kernel/locking/lockdep.c:5842 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:162 __put_partials+0x63/0x160 mm/slub.c:3866 __slab_free+0x294/0x320 mm/slub.c:5952 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349 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] __do_kmalloc_node mm/slub.c:5656 [inline] __kmalloc_node_track_caller_noprof+0x526/0x820 mm/slub.c:5764 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:608 __alloc_skb+0x204/0x3a0 net/core/skbuff.c:690 alloc_skb include/linux/skbuff.h:1383 [inline] alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6712 sock_alloc_send_pskb+0x84d/0x980 net/core/sock.c:2995 unix_dgram_sendmsg+0x454/0x1840 net/unix/af_unix.c:2130 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 __sys_sendto+0x3ca/0x520 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x8a/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f6efb5b3407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffcdc2cd610 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f6efb463c80 RCX: 00007f6efb5b3407 RDX: 000000000000003a RSI: 00007ffcdc2cd750 RDI: 0000000000000003 RBP: 00007ffcdc2cdb80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffcdc2cdb98 R13: 00007ffcdc2cd750 R14: 000000000000001f R15: 00007ffcdc2cd750