INFO: task syz.4.249:8326 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-syzkaller-00253-g4871b7cb27f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.249 state:D stack:25128 pid:8326 tgid:8275 ppid:5834 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0x165/0x360 kernel/sched/core.c:6879 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 inode_lock_shared include/linux/fs.h:884 [inline] lookup_slow+0x46/0x70 fs/namei.c:1833 walk_component+0x2d2/0x400 fs/namei.c:2138 lookup_last fs/namei.c:2639 [inline] path_lookupat+0x163/0x430 fs/namei.c:2663 filename_lookup+0x212/0x570 fs/namei.c:2692 user_path_at+0x3a/0x60 fs/namei.c:3136 __do_sys_chdir fs/open.c:560 [inline] __se_sys_chdir+0x91/0x280 fs/open.c:554 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5bde98e9a9 RSP: 002b:00007f5bdc7d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000050 RAX: ffffffffffffffda RBX: 00007f5bdebb6080 RCX: 00007f5bde98e9a9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000140 RBP: 00007f5bdea10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5bdebb6080 R15: 00007fff5c568ca8 INFO: task syz.4.249:8327 blocked for more than 144 seconds. Not tainted 6.16.0-rc6-syzkaller-00253-g4871b7cb27f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.249 state:D stack:28904 pid:8327 tgid:8275 ppid:5834 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0x165/0x360 kernel/sched/core.c:6879 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694 inode_lock_nested include/linux/fs.h:914 [inline] filename_create+0x1f9/0x470 fs/namei.c:4148 do_mkdirat+0xa0/0x590 fs/namei.c:4400 __do_sys_mkdir fs/namei.c:4430 [inline] __se_sys_mkdir fs/namei.c:4428 [inline] __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4428 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5bde98e9a9 RSP: 002b:00007f5bdc7b4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007f5bdebb6160 RCX: 00007f5bde98e9a9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000300 RBP: 00007f5bdea10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f5bdebb6160 R15: 00007fff5c568ca8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 3 locks held by kworker/u8:6/3461: 3 locks held by kworker/u8:7/3479: #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc9000c10fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000c10fbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f509908 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by dhcpcd/5498: #0: ffffffff8f4ee248 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x790 net/socket.c:1273 #1: ffffffff8f509908 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:577 2 locks held by getty/5595: #0: ffff88803140f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by udevd/5969: 5 locks held by kworker/u8:9/6735: #0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc90004567bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004567bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffffffff8f4fcd10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662 #3: ffffffff8f509908 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12630 #4: ffffffff8e144bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #4: ffffffff8e144bf8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998 5 locks held by syz.4.249/8276: #0: ffff8880595aa428 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff88805b9da740 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #1: ffff88805b9da740 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: open_last_lookups fs/namei.c:3813 [inline] #1: ffff88805b9da740 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4052 #2: ffff88805b9dab28 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:567 #3: ffff888061384398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff888061384398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff888061384398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3299 #4: ffff8880613a6710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211 1 lock held by syz.4.249/8326: #0: ffff88805b9da740 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:884 [inline] #0: ffff88805b9da740 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833 2 locks held by syz.4.249/8327: #0: ffff8880595aa428 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557 #1: ffff88805b9da740 (&sb->s_type->i_mutex_key#33/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline] #1: ffff88805b9da740 (&sb->s_type->i_mutex_key#33/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4148 2 locks held by syz-executor/10923: #0: ffffffff8f4fcd10 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:570 #1: ffffffff8f509908 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160 1 lock held by syz-executor/10957: #0: ffffffff8f509908 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff8f509908 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979 3 locks held by syz.6.510/10969: 2 locks held by syz.7.513/10997: #0: ffff8880b8639e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 #1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-syzkaller-00253-g4871b7cb27f4 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 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: 5822 Comm: syz-executor Not tainted 6.16.0-rc6-syzkaller-00253-g4871b7cb27f4 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:entry_SYSRETQ_unsafe_stack+0xa/0xd Code: 89 c7 eb 08 48 89 c7 48 0f ba ef 3f 48 81 cf 00 08 00 00 48 81 cf 00 10 00 00 0f 22 df 58 5f 5c 0f 01 f8 0f 00 2d 77 fe ff ff <48> 0f 07 cc 90 90 90 56 48 8b 74 24 08 48 89 7c 24 08 52 51 50 41 RSP: 0018:00007fff9e8faa88 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa8d138d37d RDX: 0000000000000004 RSI: 00007fff9e8faa9c RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000024255e89 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff9e8faeb0 R13: 0000000000000004 R14: 00007fff9e8faa9c R15: 00007fff9e8fab30 FS: 00005555827c8500(0000) GS:ffff888125c59000(0000) knlGS:ffff888125c59000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f395ec1a000 CR3: 000000002a180000 CR4: 00000000003526f0 Call Trace: