INFO: task syz.2.45:6277 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.45 state:D stack:20520 pid:6277 tgid:6237 ppid:5840 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 io_schedule+0x81/0xe0 kernel/sched/core.c:7903 folio_wait_bit_common+0x6b5/0xb90 mm/filemap.c:1317 __folio_lock mm/filemap.c:1675 [inline] folio_lock include/linux/pagemap.h:1133 [inline] __filemap_get_folio+0x167/0xa40 mm/filemap.c:1929 folio_hole_offset fs/bcachefs/fs-io-pagecache.c:756 [inline] bch2_seek_pagecache_hole+0xbb/0x7c0 fs/bcachefs/fs-io-pagecache.c:793 bch2_clamp_data_hole+0x8f/0x180 fs/bcachefs/fs-io-pagecache.c:808 __bchfs_fallocate+0xe77/0x1870 fs/bcachefs/fs-io.c:697 bchfs_fallocate+0x33f/0x680 fs/bcachefs/fs-io.c:789 bch2_fallocate_dispatch+0x28d/0x410 fs/bcachefs/fs-io.c:836 vfs_fallocate+0x672/0x7f0 fs/open.c:342 ksys_fallocate fs/open.c:366 [inline] __do_sys_fallocate fs/open.c:371 [inline] __se_sys_fallocate fs/open.c:369 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:369 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd8f76eba9 RSP: 002b:00007fbd8d9ad038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007fbd8f9b6090 RCX: 00007fbd8f76eba9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007fbd8f7f1e19 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000001001ec R11: 0000000000000246 R12: 0000000000000000 R13: 00007fbd8f9b6128 R14: 00007fbd8f9b6090 R15: 00007fff205052d8 INFO: task syz.2.45:6278 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.45 state:D stack:25904 pid:6278 tgid:6237 ppid:5840 task_flags:0x440040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 __bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7 bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline] bch2_readahead+0x94f/0x1100 fs/bcachefs/fs-io-buffered.c:296 read_pages+0x177/0x580 mm/readahead.c:160 page_cache_ra_unbounded+0x63b/0x740 mm/readahead.c:297 filemap_get_pages+0x443/0x1df0 mm/filemap.c:2603 filemap_splice_read+0x587/0xc60 mm/filemap.c:2991 do_splice_read fs/splice.c:982 [inline] splice_direct_to_actor+0x4b1/0xcd0 fs/splice.c:1086 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x187/0x270 fs/splice.c:1230 vfs_copy_file_range+0xad7/0x1330 fs/read_write.c:1627 __do_sys_copy_file_range fs/read_write.c:1677 [inline] __se_sys_copy_file_range+0x2fb/0x470 fs/read_write.c:1644 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd8f76eba9 RSP: 002b:00007fbd8d98c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000146 RAX: ffffffffffffffda RBX: 00007fbd8f9b6180 RCX: 00007fbd8f76eba9 RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007fbd8f7f1e19 R08: 0000000000000101 R09: 0000000000000000 R10: 00002000000000c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fbd8f9b6218 R14: 00007fbd8f9b6180 R15: 00007fff205052d8 Showing all locks held in the system: 1 lock held by khungtaskd/38: #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/43: #0: ffff88814d4a8938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88814d4a8938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90000b47bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000b47bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194 2 locks held by kworker/u8:3/57: 6 locks held by kworker/u8:8/1173: #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90004f2fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90004f2fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecc6700 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffff88803d9e70d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff88803d9e70d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline] #3: ffff88803d9e70d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x10a/0x3d0 net/devlink/core.c:506 #4: ffff88803d9e6300 (&devlink->lock_key#9){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline] #4: ffff88803d9e6300 (&devlink->lock_key#9){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline] #4: ffff88803d9e6300 (&devlink->lock_key#9){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x11c/0x3d0 net/devlink/core.c:506 #5: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x80/0x210 net/ipv4/nexthop.c:3928 2 locks held by dhcpcd/5500: #0: ffff888028672910 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2269 #1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6814 2 locks held by getty/5593: #0: ffff88823bf2e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 3 locks held by syz.2.45/6277: #0: ffff8880336ea488 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline] #0: ffff8880336ea488 (sb_writers#13){.+.+}-{0:0}, at: vfs_fallocate+0x5f9/0x7f0 fs/open.c:341 #1: ffff88805ca28178 (&sb->s_type->i_mutex_key#23){++++}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline] #1: ffff88805ca28178 (&sb->s_type->i_mutex_key#23){++++}-{4:4}, at: bch2_fallocate_dispatch+0x111/0x410 fs/bcachefs/fs-io.c:827 #2: ffff88805e404678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #2: ffff88805e404678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #2: ffff88805e404678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3299 1 lock held by syz.2.45/6278: #0: ffff88805ca28348 (mapping.invalidate_lock#8){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:935 [inline] #0: ffff88805ca28348 (mapping.invalidate_lock#8){.+.+}-{4:4}, at: page_cache_ra_unbounded+0xf4/0x740 mm/readahead.c:228 4 locks held by syz-executor/7096: #0: ffff88805b30ce80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff88805b30ce80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2715 #1: ffff88805b30c0a8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5282 #2: ffffffff8ee3b0d8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2094 [inline] #2: ffffffff8ee3b0d8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2599 #3: ffff888029c09358 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762 1 lock held by syz-executor/7271: 5 locks held by syz-executor/7288: #0: ffff8880341be488 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline] #0: ffff8880341be488 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682 #1: ffff88805bcf1878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343 #2: ffff888145353c38 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888145353c38 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344 #3: ffffffff8e542d38 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234 #4: ffff88803d9e70d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff88803d9e70d8 (&dev->mutex){....}-{4:4}, at: device_del+0xa9/0x8e0 drivers/base/core.c:3840 2 locks held by syz-executor/7336: #0: ffffffff8f1f3a30 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8f1f3a30 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8f1f3a30 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 2 locks held by syz.0.221/7470: 2 locks held by syz-executor/7469: #0: ffffffff8ecc6700 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566 #1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: register_netdevice_notifier_net+0x1a/0xa0 net/core/dev.c:2082 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 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: 7470 Comm: syz.0.221 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x29/0x80 kernel/kcov.c:217 Code: 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 40 f6 91 65 8b 35 08 d2 37 10 81 e6 00 00 ff 00 ba 00 01 00 00 23 91 0c 0b 00 00 <89> d7 09 f7 74 11 85 f6 75 39 85 d2 74 35 83 b9 d4 15 00 00 00 74 RSP: 0018:ffffc900041f78e0 EFLAGS: 00000246 RAX: ffffffff81f92f56 RBX: ffffea00018d09c0 RCX: ffff88802e253b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: fffff9400031a139 R12: 1ffffd400031a139 R13: 1ffffd400031a138 R14: 0000000000000000 R15: dffffc0000000000 FS: 00007fa6a69ee6c0(0000) GS:ffff8881269bc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa69ea75000 CR3: 0000000032834000 CR4: 00000000003526f0 Call Trace: folio_add_lru+0x106/0x220 mm/swap.c:510 shmem_alloc_and_add_folio mm/shmem.c:2006 [inline] shmem_get_folio_gfp+0xb56/0x1a70 mm/shmem.c:2597 shmem_get_folio mm/shmem.c:2703 [inline] shmem_write_begin+0xef/0x2a0 mm/shmem.c:3353 generic_perform_write+0x29a/0x8c0 mm/filemap.c:4175 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3528 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5d2/0xb40 fs/read_write.c:686 ksys_write+0x14b/0x260 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa6a878d65f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007fa6a69eddf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fa6a878d65f RDX: 0000000001000000 RSI: 00007fa69e5ce000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000983e R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000003 R13: 00007fa6a69edef0 R14: 00007fa6a69edeb0 R15: 00007fa69e5ce000