INFO: task syz-executor295:5845 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor295 state:D stack:18320 pid:5845 tgid:5845 ppid:5844 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x1b33/0x51f0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x163/0x360 kernel/sched/core.c:6860 __closure_sync+0x1c0/0x2a0 lib/closure.c:146 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:254 [inline] bch2_btree_update_start+0x12bd/0x16c0 fs/bcachefs/btree_update_interior.c:1251 bch2_btree_split_leaf+0x12d/0x8a0 fs/bcachefs/btree_update_interior.c:1864 bch2_trans_commit_error+0x1b3/0x1480 fs/bcachefs/btree_trans_commit.c:904 __bch2_trans_commit+0x8886/0x9da0 fs/bcachefs/btree_trans_commit.c:1069 bch2_trans_commit fs/bcachefs/btree_update.h:195 [inline] bch2_logged_op_start+0x22d/0x3f0 fs/bcachefs/logged_ops.c:93 bch2_truncate+0x1eb/0x340 fs/bcachefs/io_misc.c:297 bchfs_truncate+0x97b/0xc60 fs/bcachefs/fs-io.c:494 notify_change+0xbca/0xe90 fs/attr.c:552 do_truncate+0x222/0x310 fs/open.c:65 handle_truncate fs/namei.c:3501 [inline] do_open fs/namei.c:3884 [inline] path_openat+0x2e4f/0x35d0 fs/namei.c:4039 do_filp_open+0x284/0x4e0 fs/namei.c:4066 do_sys_openat2+0x12b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_open fs/open.c:1452 [inline] __se_sys_open fs/open.c:1448 [inline] __x64_sys_open+0x226/0x280 fs/open.c:1448 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f440d751b19 RSP: 002b:00007ffc957c9428 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f440d751b19 RDX: 0000000000000100 RSI: 000000000014927e RDI: 0000200000000140 RBP: 00007f440d7d45f0 R08: 000000000000f624 R09: 000055556789a4c0 R10: 00007ffc957c92f0 R11: 0000000000000246 R12: 00007ffc957c9450 R13: 00007ffc957c9678 R14: 431bde82d7b634db R15: 00007f440d79a03b Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5582: #0: ffff88814d4910a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000334b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 5 locks held by syz-executor295/5845: #0: ffff88807e204420 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff888073678148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff888073678148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: do_truncate+0x20e/0x310 fs/open.c:63 #2: ffff888074880a70 (&c->snapshot_create_lock){.+.+}-{4:4}, at: bch2_truncate+0x1ae/0x340 fs/bcachefs/io_misc.c:295 #3: ffff888074884228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff888074884228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff888074884228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7ed/0xd40 fs/bcachefs/btree_iter.c:3382 #4: ffff8880748a6590 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x68a/0x16c0 fs/bcachefs/btree_update_interior.c:1179 3 locks held by bch-copygc/loop/5855: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0x1058/0x10a0 kernel/hung_task.c:437 kthread+0x7b7/0x940 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1164 Comm: kworker/u8:6 Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:pmd_alloc include/linux/mm.h:2948 [inline] RIP: 0010:walk_to_pmd+0xd7/0x240 mm/memory.c:2060 Code: 8b 03 48 21 d0 4c 89 fb 48 c1 eb 1b 81 e3 f8 0f 00 00 48 09 c3 48 01 cb 0f 84 d9 00 00 00 49 89 dc 49 c1 ec 03 43 80 3c 2c 00 <74> 08 48 89 df e8 9f 35 1b 00 48 8b 2b 48 89 ee 48 83 e6 9f 31 ff RSP: 0018:ffffc90003e7f638 EFLAGS: 00000246 RAX: 000000001b06f000 RBX: ffff88801b06f550 RCX: ffff888000000000 RDX: 000ffffffffff000 RSI: 800000001b06f007 RDI: 0000000000000000 RBP: 800000001b06f007 R08: ffffffff820f34ca R09: 1ffffd4000010f80 R10: dffffc0000000000 R11: fffff94000010f81 R12: 1ffff1100360deaa R13: dffffc0000000000 R14: ffff88801b070000 R15: 00002aaaaaaab000 FS: 0000000000000000(0000) GS:ffff8881250cf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdef7b0f1c CR3: 000000000eb38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __get_locked_pte+0x25/0xc0 mm/memory.c:2071 get_locked_pte include/linux/mm.h:2826 [inline] __text_poke+0x2ec/0xe20 arch/x86/kernel/alternative.c:2269 text_poke arch/x86/kernel/alternative.c:2354 [inline] text_poke_bp_batch+0x8cf/0xb30 arch/x86/kernel/alternative.c:2743 text_poke_flush arch/x86/kernel/alternative.c:2856 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2863 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xd2/0x1c0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1b1/0x250 mm/kfence/core.c:855 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 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 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.266 msecs