INFO: task syz-executor160:5833 blocked for more than 143 seconds. Not tainted 6.15.0-rc2-syzkaller-00257-gb5c6891b2c5b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor160 state:D stack:20144 pid:5833 tgid:5833 ppid:5832 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:3466 [inline] do_open fs/namei.c:3849 [inline] path_openat+0x2e4f/0x35d0 fs/namei.c:4004 do_filp_open+0x284/0x4e0 fs/namei.c:4031 do_sys_openat2+0x12b/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_creat fs/open.c:1522 [inline] __se_sys_creat fs/open.c:1516 [inline] __x64_sys_creat+0x124/0x170 fs/open.c:1516 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: 0033:0x7fc232e7ab19 RSP: 002b:00007ffd56149448 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc232e7ab19 RDX: 00007fc232e79d70 RSI: 0000000000000101 RDI: 0000200000000280 RBP: 00007fc232efd5f0 R08: 000000000000f624 R09: 000055558d7e54c0 R10: 00007ffd56149310 R11: 0000000000000246 R12: 00007ffd56149470 R13: 00007ffd56149698 R14: 431bde82d7b634db R15: 00007fc232ec303b 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 1 lock held by syslogd/5183: #0: ffff8880b8639998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605 2 locks held by getty/5584: #0: ffff8880319a40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222 5 locks held by syz-executor160/5833: #0: ffff888035e6a420 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556 #1: ffff8880737c88e0 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff8880737c88e0 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: do_truncate+0x20e/0x310 fs/open.c:63 #2: ffff888075280a58 (&c->snapshot_create_lock){.+.+}-{4:4}, at: bch2_truncate+0x1ae/0x340 fs/bcachefs/io_misc.c:295 #3: ffff888075284210 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff888075284210 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff888075284210 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7ed/0xd40 fs/bcachefs/btree_iter.c:3382 #4: ffff8880752a6550 (&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/5842: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00257-gb5c6891b2c5b #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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5842 Comm: bch-copygc/loop Not tainted 6.15.0-rc2-syzkaller-00257-gb5c6891b2c5b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:bch2_trans_iter_exit+0xd3/0x300 fs/bcachefs/btree_iter.c:3027 Code: 6b fd 4d 89 ef 49 c1 ef 03 41 0f b6 04 1f 84 c0 0f 85 4f 01 00 00 41 0f b7 6d 00 31 ff 89 ee e8 23 e1 6b fd 85 ed 4c 89 24 24 <74> 49 e8 76 dd 6b fd 48 89 d9 49 8d 5d 08 48 89 d8 48 c1 e8 03 0f RSP: 0018:ffffc9000411f4d0 EFLAGS: 00000202 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff88807d6d1e00 RDX: ffff88807d6d1e00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff8456dc7d R09: 0000000000000000 R10: ffffc9000411ef40 R11: fffff52000823df4 R12: ffff8880728b0000 R13: ffffc9000411f980 R14: ffffc9000411f982 R15: 1ffff92000823f30 FS: 0000000000000000(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556147283600 CR3: 0000000030210000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bch2_copygc_get_buckets fs/bcachefs/movinggc.c:169 [inline] bch2_copygc+0x2e1f/0x4db0 fs/bcachefs/movinggc.c:221 bch2_copygc_thread+0x705/0xc00 fs/bcachefs/movinggc.c:398 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