INFO: task kworker/u4:10:4312 blocked for more than 143 seconds. Not tainted 5.15.182-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:10 state:D stack:22304 pid: 4312 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:8) Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518 __mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 jfs_commit_inode+0x1c7/0x520 fs/jfs/inode.c:102 jfs_write_inode+0x141/0x220 fs/jfs/inode.c:132 write_inode fs/fs-writeback.c:1495 [inline] __writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1705 writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1930 __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2001 wb_writeback+0x455/0xb90 fs/fs-writeback.c:2106 wb_check_background_flush fs/fs-writeback.c:2172 [inline] wb_do_writeback fs/fs-writeback.c:2260 [inline] wb_workfn+0xb47/0xe60 fs/fs-writeback.c:2288 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 INFO: task syz.8.1246:10916 blocked for more than 145 seconds. Not tainted 5.15.182-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.1246 state:D stack:27872 pid:10916 ppid: 6793 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165 inode_lock include/linux/fs.h:787 [inline] open_last_lookups fs/namei.c:3529 [inline] path_openat+0x7f3/0x2f30 fs/namei.c:3739 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f91a48de969 RSP: 002b:00007f91a2725038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f91a4b06080 RCX: 00007f91a48de969 RDX: 000000000000275a RSI: 00002000000001c0 RDI: ffffffffffffff9c RBP: 00007f91a4960ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f91a4b06080 R15: 00007ffcac56c538 INFO: task syz.8.1246:10917 blocked for more than 146 seconds. Not tainted 5.15.182-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.1246 state:D stack:29088 pid:10917 ppid: 6793 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165 inode_lock include/linux/fs.h:787 [inline] chown_common+0x3c6/0x610 fs/open.c:674 vfs_fchown fs/open.c:748 [inline] ksys_fchown+0xe2/0x150 fs/open.c:759 __do_sys_fchown fs/open.c:767 [inline] __se_sys_fchown fs/open.c:765 [inline] __x64_sys_fchown+0x76/0x80 fs/open.c:765 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f91a48de969 RSP: 002b:00007f91a2704038 EFLAGS: 00000246 ORIG_RAX: 000000000000005d RAX: ffffffffffffffda RBX: 00007f91a4b06160 RCX: 00007f91a48de969 RDX: 000000000000ee01 RSI: ffffffffffffffff RDI: 0000000000000004 RBP: 00007f91a4960ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f91a4b06160 R15: 00007ffcac56c538 Showing all locks held in the system: 3 locks held by kworker/0:1/13: #0: ffff88814c5d8538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90000d27d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d22a288 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4113 1 lock held by khungtaskd/27: #0: ffffffff8c11bea0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/u4:3/155: 2 locks held by getty/3932: #0: ffff88802c18b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cd62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 3 locks held by kworker/u4:5/4232: 4 locks held by kworker/u4:10/4312: #0: ffff888018bc8938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900031ffd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888061b880e0 (&type->s_umount_key#108){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418 #3: ffff888060ce8b08 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x1c7/0x520 fs/jfs/inode.c:102 3 locks held by kworker/1:8/4371: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90004e77d00 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8c120928 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffffffff8c120928 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 3 locks held by kworker/0:12/4478: #0: ffff88814c5d8538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000330fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d22a288 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4113 2 locks held by kworker/1:17/5181: #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900033ffd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 3 locks held by kworker/0:19/5302: #0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900033efd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8c120830 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4b0 kernel/rcu/tree.c:4039 4 locks held by syz.8.1246/10908: 2 locks held by syz.8.1246/10916: #0: ffff888061b88460 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:377 #1: ffff888060ce8ec0 (&type->i_mutex_dir_key#18){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff888060ce8ec0 (&type->i_mutex_dir_key#18){++++}-{3:3}, at: open_last_lookups fs/namei.c:3529 [inline] #1: ffff888060ce8ec0 (&type->i_mutex_dir_key#18){++++}-{3:3}, at: path_openat+0x7f3/0x2f30 fs/namei.c:3739 2 locks held by syz.8.1246/10917: #0: ffff888061b88460 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:421 #1: ffff888060ce8ec0 (&type->i_mutex_dir_key#18){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #1: ffff888060ce8ec0 (&type->i_mutex_dir_key#18){++++}-{3:3}, at: chown_common+0x3c6/0x610 fs/open.c:674 4 locks held by kworker/u4:18/11370: #0: ffff8880169cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc9000392fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d21e610 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x132/0xb80 net/core/net_namespace.c:589 #3: ffffffff8c120928 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #3: ffffffff8c120928 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845 2 locks held by syz-executor/11949: #0: ffffffff8d22a288 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d22a288 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x974/0xe60 net/core/rtnetlink.c:5647 #1: ffff8880794e93e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_open+0x223/0x420 drivers/net/wireguard/device.c:49 3 locks held by kworker/1:16/12425: #0: ffff88814c5d8538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900030efd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffffffff8d22a288 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1520 net/ipv6/addrconf.c:4113 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.182-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 10908 Comm: syz.8.1246 Not tainted 5.15.182-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:asm_sysvec_apic_timer_interrupt+0x0/0x20 arch/x86/include/asm/idtentry.h:675 Code: e9 e5 04 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 e5 03 00 00 48 89 c4 48 89 e7 e8 0a 1b e1 ff e9 c5 04 00 00 90 90 90 90 90 <0f> 01 ca fc 6a ff e8 c5 03 00 00 48 89 c4 48 89 e7 e8 5a 19 e1 ff RSP: 0018:ffffc900038df6c8 EFLAGS: 00000046 RAX: ffffffff82cc0975 RBX: ffff88804dffa000 RCX: ffff888076631dc0 RDX: ffffc900128e6000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed1009bff424 R10: 0000000000000000 R11: 0000000000000018 R12: 1ffff11009bff402 R13: dffffc0000000000 R14: 000000000000000d R15: 1ffff11009bff400 FS: 00007f91a27466c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff64a31fdc CR3: 000000007475b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x60 kernel/kcov.c:211 Code: ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 <48> 8d 7e 01 8b 89 14 16 00 00 48 39 cf 73 08 48 89 44 f2 08 48 89 RSP: 0018:ffffc900038df6f8 EFLAGS: 00000246 dtSplitRoot+0x715/0x1510 fs/jfs/jfs_dtree.c:1979 dtSplitUp fs/jfs/jfs_dtree.c:991 [inline] dtInsert+0xd90/0x5730 fs/jfs/jfs_dtree.c:869 jfs_mkdir+0x6e5/0xa70 fs/jfs/namei.c:270 vfs_mkdir+0x387/0x570 fs/namei.c:4065 do_mkdirat+0x1d7/0x5a0 fs/namei.c:4090 __do_sys_mkdir fs/namei.c:4110 [inline] __se_sys_mkdir fs/namei.c:4108 [inline] __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4108 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f91a48de969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f91a2746038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f91a4b05fa0 RCX: 00007f91a48de969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000003c0 RBP: 00007f91a4960ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f91a4b05fa0 R15: 00007ffcac56c538