INFO: task syz-executor426:5838 blocked for more than 143 seconds. Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor426 state:D stack:19624 pid:5838 tgid:5838 ppid:5837 task_flags:0x400140 flags:0x00004006 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 __closure_sync+0x163/0x220 lib/closure.c:146 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:256 [inline] bch2_btree_update_start+0x1193/0x14c0 fs/bcachefs/btree_update_interior.c:1251 bch2_btree_split_leaf+0x13c/0x8f0 fs/bcachefs/btree_update_interior.c:1864 bch2_trans_commit_error+0x1a8/0x1100 fs/bcachefs/btree_trans_commit.c:904 __bch2_trans_commit+0x779c/0x8ae0 fs/bcachefs/btree_trans_commit.c:1069 bch2_trans_commit fs/bcachefs/btree_update.h:195 [inline] __bch2_create+0x887/0xb90 fs/bcachefs/fs.c:593 bch2_mknod fs/bcachefs/fs.c:750 [inline] bch2_create+0x66/0xd0 fs/bcachefs/fs.c:764 lookup_open fs/namei.c:3701 [inline] open_last_lookups fs/namei.c:3800 [inline] path_openat+0x14f1/0x3830 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: 0033:0x7fa1ac368b59 RSP: 002b:00007ffd1ccdcad8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fa1ac368b59 RDX: 000000000000275a RSI: 0000200000000100 RDI: 00000000ffffff9c RBP: 00007fa1ac3eb5f0 R08: 000000000000f624 R09: 00005555663b64c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd1ccdcb00 R13: 00007ffd1ccdcd28 R14: 431bde82d7b634db R15: 00007fa1ac3b103b Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5575: #0: ffff888030b170a0 (&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 5 locks held by syz-executor426/5838: #0: ffff88807d608420 (sb_writers#8){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556 #1: ffff88807a6f8148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #1: ffff88807a6f8148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline] #1: ffff88807a6f8148 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036 #2: ffff88807a6f8530 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:567 #3: ffff888078884228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff888078884228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff888078884228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385 #4: ffff8880788a6590 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179 3 locks held by bch-copygc/loop/5848: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 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: 5174 Comm: syslogd Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:iterate_ubuf include/linux/iov_iter.h:30 [inline] RIP: 0010:iterate_and_advance2 include/linux/iov_iter.h:300 [inline] RIP: 0010:iterate_and_advance include/linux/iov_iter.h:328 [inline] RIP: 0010:_copy_to_iter+0x1a5/0x15a0 lib/iov_iter.c:185 Code: 8e e8 bf e5 10 fd 45 85 ff 0f 85 88 01 00 00 49 8d 7e 10 48 89 f8 48 c1 e8 03 42 80 3c 20 00 74 05 e8 7f af 70 fd 4d 8b 6e 10 <49> 83 c6 08 4d 89 f4 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df 41 RSP: 0018:ffffc900039bf760 EFLAGS: 00000246 RAX: 1ffff92000737f7c RBX: ffffc900039bfbe8 RCX: 0000000000000001 RDX: ffffffff84aedda1 RSI: ffffffff8e6a2060 RDI: ffffc900039bfbe0 RBP: ffffc900039bf8b8 R08: ffff88805ba25a00 R09: 0000000000000006 R10: 0000000000000005 R11: 0000000000000000 R12: dffffc0000000000 R13: 00005628fa9dd950 R14: ffffc900039bfbd0 R15: 0000000000000000 FS: 00007f84a3823380(0000) GS:ffff888126102000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005556672a7600 CR3: 0000000033c30000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: copy_to_iter include/linux/uio.h:220 [inline] simple_copy_to_iter net/core/datagram.c:524 [inline] __skb_datagram_iter+0x100/0x960 net/core/datagram.c:401 skb_copy_datagram_iter+0xc5/0x230 net/core/datagram.c:538 skb_copy_datagram_msg include/linux/skbuff.h:4128 [inline] __unix_dgram_recvmsg+0x665/0xdc0 net/unix/af_unix.c:2464 sock_recvmsg_nosec net/socket.c:1017 [inline] sock_recvmsg+0x229/0x270 net/socket.c:1039 sock_read_iter+0x231/0x2f0 net/socket.c:1109 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4cd/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 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: 0033:0x7f84a3977b6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fff10196398 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f84a3977b6a RDX: 00000000000000ff RSI: 00005628fa9dd950 RDI: 0000000000000000 RBP: 00005628fa9dd910 R08: 0000000000000001 R09: 0000000000000000 R10: 00007f84a3b163a3 R11: 0000000000000246 R12: 00005628fa9dd99d R13: 00005628fa9dd950 R14: 0000000000000000 R15: 00007f84a3b5ca80