__gup_longterm_unlocked mm/gup.c:2678 [inline] internal_get_user_pages_fast+0x175f/0x2640 mm/gup.c:2766 get_user_pages_fast+0x66/0xa0 mm/gup.c:2858 ====================================================== iov_iter_get_pages+0x297/0xf40 lib/iov_iter.c:1321 WARNING: possible circular locking dependency detected 5.10.229 #1 Not tainted ------------------------------------------------------ syz-executor.2/96237 is trying to acquire lock: __bio_iov_iter_get_pages block/bio.c:1021 [inline] bio_iov_iter_get_pages+0x22a/0x1200 block/bio.c:1129 ffff888017ef8b78 ( (work_completion)(&hdev->bg_scan_update) ){+.+.}-{0:0}, at: __flush_work+0xdd/0xa90 kernel/workqueue.c:3050 but task is already holding lock: ffffffff8561e2c8 (rfkill_global_mutex ){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: iomap_dio_bio_actor+0x77a/0xef0 fs/iomap/direct-io.c:284 -> #4 iomap_dio_actor+0x36f/0x560 fs/iomap/direct-io.c:391 (rfkill_global_mutex iomap_apply+0x289/0x810 fs/iomap/apply.c:84 ){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 rfkill_register+0x36/0xa10 net/rfkill/core.c:1016 hci_register_dev+0x42e/0xc00 net/bluetooth/hci_core.c:3774 __vhci_create_device+0x2c8/0x5c0 drivers/bluetooth/hci_vhci.c:129 vhci_create_device drivers/bluetooth/hci_vhci.c:153 [inline] vhci_open_timeout+0x38/0x50 drivers/bluetooth/hci_vhci.c:310 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:328 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:298 __iomap_dio_rw+0x6cd/0x1110 fs/iomap/direct-io.c:519 -> #3 ( &data->open_mutex){+.+.}-{3:3} : __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 vhci_send_frame+0x63/0xa0 drivers/bluetooth/hci_vhci.c:71 hci_send_frame+0x1b9/0x320 net/bluetooth/hci_core.c:4065 hci_sched_acl_pkt net/bluetooth/hci_core.c:4590 [inline] hci_sched_acl net/bluetooth/hci_core.c:4675 [inline] hci_tx_work+0xfb4/0x15d0 net/bluetooth/hci_core.c:4741 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 iomap_dio_rw+0x31/0x90 fs/iomap/direct-io.c:607 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:328 ext4_dio_read_iter fs/ext4/file.c:77 [inline] ext4_file_read_iter fs/ext4/file.c:129 [inline] ext4_file_read_iter+0x2c7/0x4c0 fs/ext4/file.c:114 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:298 -> #2 call_read_iter include/linux/fs.h:1998 [inline] new_sync_read+0x424/0x6f0 fs/read_write.c:415 ((work_completion)(&hdev->tx_work) ){+.+.}-{0:0}: __flush_work+0x105/0xa90 kernel/workqueue.c:3053 hci_dev_do_close+0x131/0x1240 net/bluetooth/hci_core.c:1745 hci_unregister_dev+0x179/0x460 net/bluetooth/hci_core.c:3854 vfs_read+0x4da/0x620 fs/read_write.c:496 vhci_release+0x70/0xf0 drivers/bluetooth/hci_vhci.c:345 __fput+0x285/0x9f0 fs/file_table.c:281 ksys_read+0x12d/0x260 fs/read_write.c:634 task_work_run+0xe2/0x1a0 kernel/task_work.c:185 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xb6f/0x2600 kernel/exit.c:860 do_group_exit+0x125/0x310 kernel/exit.c:982 get_signal+0x4bc/0x2350 kernel/signal.c:2762 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 arch_do_signal_or_restart+0x2b7/0x1990 arch/x86/kernel/signal.c:805 handle_signal_work kernel/entry/common.c:145 [inline] exit_to_user_mode_loop kernel/entry/common.c:169 [inline] exit_to_user_mode_prepare+0x10f/0x190 kernel/entry/common.c:199 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x7f73b4409b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 syscall_exit_to_user_mode+0x38/0x1d0 kernel/entry/common.c:274 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RSP: 002b:00007f73b197f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f73b451cf60 RCX: 00007f73b4409b19 RDX: 00000000201b4000 RSI: 0000000020000000 RDI: 0000000000000003 -> #1 ( RBP: 00007f73b197f1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffe5858a7cf R14: 00007f73b197f300 R15: 0000000000022000 &hdev->req_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:968 [inline] __mutex_lock+0x13d/0x10b0 kernel/locking/mutex.c:1109 hci_req_sync net/bluetooth/hci_request.c:277 [inline] bg_scan_update+0x82/0x500 net/bluetooth/hci_request.c:2897 process_one_work+0x9a9/0x14b0 kernel/workqueue.c:2282 worker_thread+0x61d/0x1310 kernel/workqueue.c:2428 kthread+0x38f/0x470 kernel/kthread.c:328 ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:298 -> #0 ((work_completion)(&hdev->bg_scan_update)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:2988 [inline] check_prevs_add kernel/locking/lockdep.c:3113 [inline] validate_chain kernel/locking/lockdep.c:3729 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955 lock_acquire kernel/locking/lockdep.c:5566 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144 hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3440 hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341 rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240 vfs_write+0x29a/0xb10 fs/read_write.c:603 ksys_write+0x1f6/0x260 fs/read_write.c:658 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 other info that might help us debug this: Chain exists of: (work_completion)(&hdev->bg_scan_update) --> &data->open_mutex --> rfkill_global_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rfkill_global_mutex); lock(&data->open_mutex); lock(rfkill_global_mutex); lock((work_completion)(&hdev->bg_scan_update)); *** DEADLOCK *** 1 lock held by syz-executor.2/96237: #0: ffffffff8561e2c8 (rfkill_global_mutex){+.+.}-{3:3}, at: rfkill_fop_write+0xff/0x4b0 net/rfkill/core.c:1232 stack backtrace: CPU: 0 PID: 96237 Comm: syz-executor.2 Not tainted 5.10.229 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 check_noncircular+0x263/0x2e0 kernel/locking/lockdep.c:2123 check_prev_add kernel/locking/lockdep.c:2988 [inline] check_prevs_add kernel/locking/lockdep.c:3113 [inline] validate_chain kernel/locking/lockdep.c:3729 [inline] __lock_acquire+0x29e7/0x5b00 kernel/locking/lockdep.c:4955 lock_acquire kernel/locking/lockdep.c:5566 [inline] lock_acquire+0x197/0x470 kernel/locking/lockdep.c:5531 __flush_work+0x105/0xa90 kernel/workqueue.c:3053 __cancel_work_timer+0x368/0x4c0 kernel/workqueue.c:3144 hci_request_cancel_all+0x73/0x230 net/bluetooth/hci_request.c:3440 hci_dev_do_close+0xd9/0x1240 net/bluetooth/hci_core.c:1733 hci_rfkill_set_block+0x166/0x1a0 net/bluetooth/hci_core.c:2223 rfkill_set_block+0x1fd/0x540 net/rfkill/core.c:341 rfkill_fop_write+0x253/0x4b0 net/rfkill/core.c:1240 vfs_write+0x29a/0xb10 fs/read_write.c:603 ksys_write+0x1f6/0x260 fs/read_write.c:658 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x7fe4e0c88b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe4de1fe188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe4e0d9bf60 RCX: 00007fe4e0c88b19 RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003 RBP: 00007fe4e0ce2f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd9877495f R14: 00007fe4de1fe300 R15: 0000000000022000 hpet: Lost 14 RTC interrupts FAULT_INJECTION: forcing a failure. name fail_page_alloc, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 96451 Comm: syz-executor.5 Not tainted 5.10.229 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 fail_dump lib/fault-inject.c:52 [inline] should_fail.cold+0x5/0xa lib/fault-inject.c:146 prepare_alloc_pages mm/page_alloc.c:4941 [inline] __alloc_pages_nodemask+0x182/0x600 mm/page_alloc.c:4983 alloc_pages_vma+0xbb/0x410 mm/mempolicy.c:2229 alloc_zeroed_user_highpage_movable include/linux/highmem.h:277 [inline] do_anonymous_page mm/memory.c:3635 [inline] handle_pte_fault mm/memory.c:4495 [inline] __handle_mm_fault mm/memory.c:4632 [inline] handle_mm_fault+0x152f/0x3500 mm/memory.c:4730 faultin_page mm/gup.c:891 [inline] __get_user_pages+0x6ec/0x1620 mm/gup.c:1103 __get_user_pages_locked mm/gup.c:1289 [inline] get_user_pages_unlocked+0x18a/0x690 mm/gup.c:2029 __gup_longterm_unlocked mm/gup.c:2678 [inline] internal_get_user_pages_fast+0x175f/0x2640 mm/gup.c:2766 get_user_pages_fast+0x66/0xa0 mm/gup.c:2858 iov_iter_get_pages+0x297/0xf40 lib/iov_iter.c:1321 __bio_iov_iter_get_pages block/bio.c:1021 [inline] bio_iov_iter_get_pages+0x22a/0x1200 block/bio.c:1129 iomap_dio_bio_actor+0x77a/0xef0 fs/iomap/direct-io.c:284 iomap_dio_actor+0x36f/0x560 fs/iomap/direct-io.c:391 iomap_apply+0x289/0x810 fs/iomap/apply.c:84 __iomap_dio_rw+0x6cd/0x1110 fs/iomap/direct-io.c:519 iomap_dio_rw+0x31/0x90 fs/iomap/direct-io.c:607 ext4_dio_read_iter fs/ext4/file.c:77 [inline] ext4_file_read_iter fs/ext4/file.c:129 [inline] ext4_file_read_iter+0x2c7/0x4c0 fs/ext4/file.c:114 call_read_iter include/linux/fs.h:1998 [inline] new_sync_read+0x424/0x6f0 fs/read_write.c:415 vfs_read+0x4da/0x620 fs/read_write.c:496 ksys_read+0x12d/0x260 fs/read_write.c:634 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 RIP: 0033:0x7f73b4409b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f73b197f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007f73b451cf60 RCX: 00007f73b4409b19 RDX: 00000000201b4000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00007f73b197f1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffe5858a7cf R14: 00007f73b197f300 R15: 0000000000022000 hpet: Lost 2 RTC interrupts hpet: Lost 1 RTC interrupts