INFO: task syz.4.97:6781 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.97 state:D stack:25208 pid:6781 tgid:6773 ppid:5822 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 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+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:867 [inline] open_last_lookups fs/namei.c:3797 [inline] path_openat+0x8da/0x3830 fs/namei.c:4036 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f624138e969 RSP: 002b:00007f6242236038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f62415b6080 RCX: 00007f624138e969 RDX: 0000000000141042 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007f6241410ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f62415b6080 R15: 00007fffb48f0aa8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by kworker/u8:3/53: #0: ffff8880b89399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 #1: ffffc90000be7c60 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000be7c60 ((work_completion)(&worker->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 4 locks held by kworker/u8:4/63: #0: ffff888020a8b948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888020a8b948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90001557c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90001557c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff888023bb00e0 (&type->s_umount_key#84){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562 #3: ffff888056acd4c0 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102 2 locks held by udevd/5191: 2 locks held by getty/5576: #0: ffff8880332400a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900033532f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/5825: #0: ffff888033a540e0 (&type->s_umount_key#52){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888033a540e0 (&type->s_umount_key#52){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888033a540e0 (&type->s_umount_key#52){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffff888050c00278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xfe/0x5a0 fs/bcachefs/super.c:627 4 locks held by syz.4.97/6774: 2 locks held by syz.4.97/6781: #0: ffff888023bb0420 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff888056acd870 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888056acd870 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff888056acd870 (&type->i_mutex_dir_key#16){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036 3 locks held by bch-reclaim/loo/7025: #0: ffff888050c4ad28 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:765 #1: ffff888050c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #1: ffff888050c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #1: ffff888050c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385 #2: ffff888050c045d0 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x1829/0x19a0 fs/bcachefs/btree_write_buffer.c:569 3 locks held by bch-copygc/loop/7026: #0: ffff888050c045d0 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x1829/0x19a0 fs/bcachefs/btree_write_buffer.c:569 #1: ffff888050c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #1: ffff888050c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #1: ffff888050c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3202 #2: ffff888050c26590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179 1 lock held by syz-executor/8018: #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #0: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 2 locks held by syz.8.305/9007: #0: ffff888023e280e0 (&type->s_umount_key#51/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:344 #1: ffffffff8df43680 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774 2 locks held by syz.1.309/9018: #0: ffff88802c47c0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802c47c0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802c47c0e0 (&type->s_umount_key#53){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 #1: ffffffff8df43680 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774 6 locks held by dhcpcd-run-hook/9064: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #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:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 3439 Comm: kworker/u8:8 Not tainted 6.15.0-rc6-syzkaller-00047-ge9565e23cd89 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:trace_tlb_flush+0x33/0x140 include/trace/events/tlb.h:38 Code: 8b 05 35 eb fe 10 83 f8 08 73 3f 89 c3 c1 e8 06 48 8d 3c c5 70 d2 7d 8f be 08 00 00 00 e8 b5 5d ac 00 48 0f a3 1d 4d 6d 0a 0e <73> 12 e8 76 b3 33 00 84 c0 75 09 80 3d c2 69 f4 0d 00 74 12 5b 41 RSP: 0018:ffffc9000be1f638 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8173651b RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f7dd270 RBP: ffffc9000be1f730 R08: ffffffff8f7dd277 R09: 1ffffffff1efba4e R10: dffffc0000000000 R11: fffffbfff1efba4f R12: dffffc0000000000 R13: ffff88801a070000 R14: ffffffffffffffff R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881260fb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff922095e9c CR3: 000000000dd38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: switch_mm_irqs_off+0x4fc/0x810 arch/x86/mm/tlb.c:-1 unuse_temporary_mm arch/x86/kernel/alternative.c:2497 [inline] __text_poke+0x7a7/0xbf0 arch/x86/kernel/alternative.c:2607 text_poke arch/x86/kernel/alternative.c:2650 [inline] text_poke_bp_batch+0x4e5/0x940 arch/x86/kernel/alternative.c:2983 text_poke_flush arch/x86/kernel/alternative.c:3152 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:3159 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xc5/0x1b0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1a1/0x240 mm/kfence/core.c:855 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245