INFO: task kworker/u8:3:50 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:3 state:D stack:21112 pid:50 tgid:50 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:9) Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 jfs_flush_journal+0x729/0xef0 fs/jfs/jfs_logmgr.c:1563 jfs_write_inode+0x12f/0x220 fs/jfs/inode.c:134 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0x7e1/0x1230 fs/fs-writeback.c:1802 writeback_sb_inodes+0x92e/0x1940 fs/fs-writeback.c:2030 wb_writeback+0x445/0xad0 fs/fs-writeback.c:2216 wb_do_writeback fs/fs-writeback.c:2363 [inline] wb_workfn+0x3f8/0xef0 fs/fs-writeback.c:2403 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INFO: task jfsCommit:112 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jfsCommit state:D stack:26904 pid:112 tgid:112 ppid:2 task_flags:0x200040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 io_schedule+0x7f/0xd0 kernel/sched/core.c:7791 __lock_metapage fs/jfs/jfs_metapage.c:52 [inline] lock_metapage+0x1ff/0x400 fs/jfs/jfs_metapage.c:66 __get_metapage+0x49a/0xde0 fs/jfs/jfs_metapage.c:748 diIAGRead+0xce/0x140 fs/jfs/jfs_imap.c:2672 diFree+0x9de/0x2ca0 fs/jfs/jfs_imap.c:959 jfs_evict_inode+0x331/0x440 fs/jfs/inode.c:162 evict+0x61e/0xb10 fs/inode.c:837 txLazyCommit fs/jfs/jfs_txnmgr.c:2665 [inline] jfs_lazycommit+0x43d/0xaa0 fs/jfs/jfs_txnmgr.c:2734 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 INFO: task syz.9.6598:410 blocked for more than 146 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.6598 state:D stack:25112 pid:410 tgid:408 ppid:30081 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 diAlloc+0x1b5/0x1680 fs/jfs/jfs_imap.c:-1 ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56 jfs_mkdir+0x1e1/0xb00 fs/jfs/namei.c:225 vfs_mkdir+0x753/0x870 fs/namei.c:5139 do_mkdirat+0x27d/0x4b0 fs/namei.c:5173 __do_sys_mkdirat fs/namei.c:5195 [inline] __se_sys_mkdirat fs/namei.c:5193 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5193 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f80dd999d97 RSP: 002b:00007f80dbbf5e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f80dbbf5ee0 RCX: 00007f80dd999d97 RDX: 00000000000001ff RSI: 0000200000000280 RDI: 00000000ffffff9c RBP: 0000200000000040 R08: 00002000000007c0 R09: 0000000000000000 R10: 0000200000000040 R11: 0000000000000246 R12: 0000200000000280 R13: 00007f80dbbf5ea0 R14: 0000000000000000 R15: 0000000000000000 INFO: task syz.4.6605:426 blocked for more than 146 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.6605 state:D stack:26584 pid:426 tgid:425 ppid:27418 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0x14ea/0x5050 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0x164/0x360 kernel/sched/core.c:6964 wb_wait_for_completion+0x372/0x690 fs/fs-writeback.c:226 sync_inodes_sb+0x1de/0xbd0 fs/fs-writeback.c:2907 __iterate_supers+0x13d/0x290 fs/super.c:924 ksys_sync+0xa0/0x170 fs/sync.c:102 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe85c39aeb9 RSP: 002b:00007fe85a5f6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fe85c615fa0 RCX: 00007fe85c39aeb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fe85c615fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe85c616038 R14: 00007fe85c615fa0 R15: 00007ffe73928ba8 Showing all locks held in the system: 1 lock held by khungtaskd/32: #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e55a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:3/50: #0: ffff888141af5948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline] #0: ffff888141af5948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340 #1: ffffc90000bb7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline] #1: ffffc90000bb7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340 2 locks held by jfsCommit/112: #0: ffff888028810920 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diFree+0x2e9/0x2ca0 fs/jfs/jfs_imap.c:889 #1: ffff8880782ca5d8 (&jfs_ip->rdwrlock/1){++++}-{4:4}, at: diFree+0x307/0x2ca0 fs/jfs/jfs_imap.c:894 1 lock held by dhcpcd/5484: 2 locks held by getty/5576: #0: ffff888034c220a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by syz.9.6598/410: #0: ffff88801feae420 (sb_writers#38){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499 #1: ffff8880782cbc68 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline] #1: ffff8880782cbc68 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline] #1: ffff8880782cbc68 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline] #1: ffff8880782cbc68 (&type->i_mutex_dir_key#23/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4888 #2: ffff888028810920 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diAlloc+0x1b5/0x1680 fs/jfs/jfs_imap.c:-1 2 locks held by syz.4.6605/426: #0: ffff88801feae0e0 (&type->s_umount_key#113){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff88801feae0e0 (&type->s_umount_key#113){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:121 #1: ffff888024ab4820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline] #1: ffff888024ab4820 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c2/0xbd0 fs/fs-writeback.c:2905 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP 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: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+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5484 Comm: dhcpcd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:unwind_next_frame+0x484/0x23c0 arch/x86/kernel/unwind_orc.c:520 Code: d2 84 c0 48 0f 45 d1 48 89 15 88 7c 83 11 48 85 d2 0f 84 40 02 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 66 18 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f RSP: 0018:ffffc90002f97418 EFLAGS: 00000213 RAX: 0000000000000000 RBX: ffffffff90105fa0 RCX: ffffffff90105fa8 RDX: ffffffff90903952 RSI: ffffffff9090393a RDI: ffffffff8c0739a0 RBP: dffffc0000000000 R08: 000000000000000a R09: ffffffff8e55a360 R10: dffffc0000000000 R11: ffffffff81afb170 R12: ffffffff90903956 R13: ffffffff90903957 R14: ffffc90002f974e8 R15: ffffffff90105fa4 FS: 00007f2f402f7740(0000) GS:ffff8881256f5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f15da7e1198 CR3: 0000000078da7000 CR4: 0000000000350ef0 Call Trace: 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:2540 [inline] slab_free mm/slub.c:6674 [inline] kfree+0x1be/0x650 mm/slub.c:6882 skb_kfree_head net/core/skbuff.c:1068 [inline] skb_free_head net/core/skbuff.c:1080 [inline] skb_release_data+0x6b5/0x8e0 net/core/skbuff.c:1107 skb_release_all net/core/skbuff.c:1182 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1196 __unix_dgram_recvmsg+0x9d0/0xd50 net/unix/af_unix.c:2658 sock_recvmsg_nosec net/socket.c:1078 [inline] sock_recvmsg+0x22c/0x270 net/socket.c:1100 sock_read_iter+0x251/0x320 net/socket.c:1170 new_sync_read fs/read_write.c:491 [inline] vfs_read+0x582/0xa70 fs/read_write.c:572 ksys_read+0x150/0x270 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2f40381407 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:00007ffd869e5220 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f2f402f7740 RCX: 00007f2f40381407 RDX: 0000000000000408 RSI: 00007ffd869e5270 RDI: 0000000000000007 RBP: 00007ffd869e5980 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00005631776c05e0 R13: 0000563188450d40 R14: 0000000000000000 R15: 00007ffd869e5730