IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready ====================================================== WARNING: possible circular locking dependency detected IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready 4.19.157-syzkaller #0 Not tainted ------------------------------------------------------ kworker/0:3/8393 is trying to acquire lock: 00000000f5b3c2b5 (&sb->s_type->i_mutex_key#10){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] 00000000f5b3c2b5 (&sb->s_type->i_mutex_key#10){+.+.}, at: __generic_file_fsync+0xb0/0x1f0 fs/libfs.c:987 wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 but task is already holding lock: 00000000fa5609a0 ((work_completion)(&dio->complete_work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130 which lock already depends on the new lock. ieee80211 phy11: Selected rate control algorithm 'minstrel_ht' the existing dependency chain (in reverse order) is: wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 -> #2 ((work_completion)(&dio->complete_work)){+.+.}: worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #1 ((wq_completion)"dio/%s"sb->s_id){+.+.}: IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready drain_workqueue+0x1a5/0x460 kernel/workqueue.c:2828 destroy_workqueue+0x75/0x790 kernel/workqueue.c:4172 sb_init_dio_done_wq+0x72/0x90 fs/direct-io.c:634 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 do_blockdev_direct_IO fs/direct-io.c:1284 [inline] __blockdev_direct_IO+0x5f18/0xeee6 fs/direct-io.c:1418 ext4_direct_IO_write fs/ext4/inode.c:3769 [inline] ext4_direct_IO+0xae4/0x1c50 fs/ext4/inode.c:3907 generic_file_direct_write+0x208/0x4a0 mm/filemap.c:3073 __generic_file_write_iter+0x2d0/0x610 mm/filemap.c:3252 ext4_file_write_iter+0x2fe/0xf20 fs/ext4/file.c:272 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 call_write_iter include/linux/fs.h:1821 [inline] aio_write+0x37f/0x5c0 fs/aio.c:1574 __io_submit_one fs/aio.c:1858 [inline] io_submit_one+0xecd/0x20c0 fs/aio.c:1909 __do_sys_io_submit fs/aio.c:1953 [inline] __se_sys_io_submit+0x11b/0x4a0 fs/aio.c:1924 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&sb->s_type->i_mutex_key#10){+.+.}: down_write+0x34/0x90 kernel/locking/rwsem.c:70 inode_lock include/linux/fs.h:748 [inline] __generic_file_fsync+0xb0/0x1f0 fs/libfs.c:987 ext4_sync_file+0xa35/0x1420 fs/ext4/fsync.c:118 vfs_fsync_range+0x13a/0x220 fs/sync.c:197 generic_write_sync include/linux/fs.h:2751 [inline] dio_complete+0x763/0xac0 fs/direct-io.c:329 process_one_work+0x864/0x1570 kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#10 --> (wq_completion)"dio/%s"sb->s_id --> (work_completion)(&dio->complete_work) Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((work_completion)(&dio->complete_work)); lock((wq_completion)"dio/%s"sb->s_id); lock((work_completion)(&dio->complete_work)); lock(&sb->s_type->i_mutex_key#10); *** DEADLOCK *** 2 locks held by kworker/0:3/8393: #0: 0000000032790d83 ((wq_completion)"dio/%s"sb->s_id){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2126 #1: 00000000fa5609a0 ((work_completion)(&dio->complete_work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130 stack backtrace: CPU: 0 PID: 8393 Comm: kworker/0:3 Not tainted 4.19.157-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: dio/sda1 dio_aio_complete_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2fe lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1865 [inline] check_prevs_add kernel/locking/lockdep.c:1978 [inline] validate_chain kernel/locking/lockdep.c:2419 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3415 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907 down_write+0x34/0x90 kernel/locking/rwsem.c:70 inode_lock include/linux/fs.h:748 [inline] __generic_file_fsync+0xb0/0x1f0 fs/libfs.c:987 ext4_sync_file+0xa35/0x1420 fs/ext4/fsync.c:118 vfs_fsync_range+0x13a/0x220 fs/sync.c:197 generic_write_sync include/linux/fs.h:2751 [inline] dio_complete+0x763/0xac0 fs/direct-io.c:329 process_one_work+0x864/0x1570 kernel/workqueue.c:2155 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 ieee80211 phy12: Selected rate control algorithm 'minstrel_ht' IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready wlan0: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan0: Creating new IBSS network, BSSID 50:50:50:50:50:50 ieee80211 phy13: Selected rate control algorithm 'minstrel_ht' IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready