INFO: task syz.2.19:5456 blocked for more than 143 seconds. Not tainted 6.11.0-syzkaller-11653-g3630400697a3 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.19 state:D stack:24032 pid:5456 tgid:5429 ppid:5216 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 io_schedule+0x8d/0x110 kernel/sched/core.c:7552 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1309 folio_wait_writeback+0xe7/0x1e0 mm/page-writeback.c:3189 truncate_inode_pages_range+0xafd/0xfc0 mm/truncate.c:398 bchfs_fallocate+0x2d1/0x730 fs/bcachefs/fs-io.c:718 bch2_fallocate_dispatch+0x3ac/0x540 fs/bcachefs/fs-io.c:771 vfs_fallocate+0x569/0x6e0 fs/open.c:333 do_vfs_ioctl+0x2583/0x2e40 fs/ioctl.c:886 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2451b7dff9 RSP: 002b:00007f24528e2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f2451d36058 RCX: 00007f2451b7dff9 RDX: 0000000020000180 RSI: 0000000040305839 RDI: 0000000000000008 RBP: 00007f2451bf0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2451d36058 R15: 00007fff9c50dcf8 Showing all locks held in the system: 2 locks held by kworker/u8:0/11: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90000107d00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000107d00 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6701 3 locks held by kworker/u8:2/35: 5 locks held by kworker/u8:4/61: #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baeb148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900015c7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900015c7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcb2450 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:580 #3: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xaa0 net/core/dev.c:11930 #4: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #4: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 2 locks held by kworker/u8:8/1126: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90003ee7d00 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003ee7d00 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 3 locks held by kworker/u8:9/3033: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc9000a077d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000a077d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by dhcpcd/4888: #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1aa0 net/ipv4/devinet.c:1097 2 locks held by getty/4977: #0: ffff88802e9930a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz.4.5/5323: #0: ffff8880322c02b8 (&f->f_pos_lock){+.+.}-{3:3}, at: fdget_pos+0x24e/0x320 fs/file.c:1187 #1: ffff888028c46420 (sb_writers#16){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #1: ffff888028c46420 (sb_writers#16){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 3 locks held by bch-reclaim/loo/5334: 1 lock held by syz.2.19/5430: #0: ffff888020f1c420 (sb_writers#16){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff888020f1c420 (sb_writers#16){.+.+}-{0:0}, at: vfs_write+0x224/0xc90 fs/read_write.c:679 2 locks held by syz.2.19/5456: #0: ffff888020f1c420 (sb_writers#16){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2931 [inline] #0: ffff888020f1c420 (sb_writers#16){.+.+}-{0:0}, at: vfs_fallocate+0x4fe/0x6e0 fs/open.c:332 #1: ffff88805fb397b0 (&sb->s_type->i_mutex_key#22){++++}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88805fb397b0 (&sb->s_type->i_mutex_key#22){++++}-{3:3}, at: bch2_fallocate_dispatch+0x1e2/0x540 fs/bcachefs/fs-io.c:762 2 locks held by bch-copygc/loop/5447: 2 locks held by syz.0.133/6008: #0: ffff888028c460e0 (&type->s_umount_key#61){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff888028c460e0 (&type->s_umount_key#61){++++}-{3:3}, at: super_lock+0x27c/0x400 fs/super.c:120 #1: ffff888028c46938 (&s->s_sync_lock){+.+.}-{3:3}, at: wait_sb_inodes fs/fs-writeback.c:2619 [inline] #1: ffff888028c46938 (&s->s_sync_lock){+.+.}-{3:3}, at: sync_inodes_sb+0x32e/0xb50 fs/fs-writeback.c:2802 1 lock held by syz-executor/6412: #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 1 lock held by syz-executor/6555: #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fcbef48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6643 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller-11653-g3630400697a3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5334 Comm: bch-reclaim/loo Not tainted 6.11.0-syzkaller-11653-g3630400697a3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x35/0x90 kernel/kcov.c:300 Code: 14 25 80 d7 03 00 65 8b 05 50 20 6f 7e 25 00 01 ff 00 74 10 3d 00 01 00 00 75 5b 83 ba 1c 16 00 00 00 74 52 8b 82 f8 15 00 00 <83> f8 03 75 47 48 8b 8a 00 16 00 00 44 8b 8a fc 15 00 00 49 c1 e1 RSP: 0018:ffffc90004167200 EFLAGS: 00000046 RAX: 0000000000000000 RBX: fffffffffffa5d8a RCX: ffff888029c58000 RDX: ffff888029c58000 RSI: 0000000000000008 RDI: 0000000000000020 RBP: 00000000001bec76 R08: ffffffff843c9f65 R09: fffff5200082ce3c R10: dffffc0000000000 R11: fffff5200082ce3c R12: 1ffff1100bc8a166 R13: ffff88805e450b30 R14: 0000000000164a00 R15: 0000000000000008 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f47ad8d4000 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: fast_divpow2 fs/bcachefs/mean_and_variance.h:170 [inline] mean_and_variance_weighted_update+0xe5/0x2f0 fs/bcachefs/mean_and_variance.c:121 time_stats_update_one+0x6b0/0x7b0 fs/bcachefs/time_stats.c:93 __bch2_time_stats_update+0x1c6/0x370 fs/bcachefs/time_stats.c:128 bch2_trans_begin+0x785/0x1c00 fs/bcachefs/btree_iter.c:3094 bch2_btree_write_buffer_flush_locked+0x15e/0x59f0 fs/bcachefs/btree_write_buffer.c:281 btree_write_buffer_flush_seq+0x1a43/0x1bc0 fs/bcachefs/btree_write_buffer.c:510 bch2_btree_write_buffer_journal_flush+0x4e/0x80 fs/bcachefs/btree_write_buffer.c:525 journal_flush_pins+0x5f7/0xb20 fs/bcachefs/journal_reclaim.c:565 __bch2_journal_reclaim+0x789/0xdc0 fs/bcachefs/journal_reclaim.c:698 bch2_journal_reclaim_thread+0x174/0x560 fs/bcachefs/journal_reclaim.c:740 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244