====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/14954 is trying to acquire lock: 0000000085633cec ((wq_completion)"dio/%s"sb->s_id){+.+.}, at: flush_workqueue+0xe8/0x13e0 kernel/workqueue.c:2658 but task is already holding lock: 000000007579d4f4 (&sb->s_type->i_mutex_key#24){++++}, at: inode_lock include/linux/fs.h:748 [inline] 000000007579d4f4 (&sb->s_type->i_mutex_key#24){++++}, at: generic_file_write_iter+0x99/0x730 mm/filemap.c:3320 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sb->s_type->i_mutex_key#24){++++}: inode_lock include/linux/fs.h:748 [inline] __generic_file_fsync+0xb0/0x1f0 fs/libfs.c:989 fat_file_fsync+0x73/0x200 fs/fat/file.c:198 vfs_fsync_range+0x13a/0x220 fs/sync.c:197 generic_write_sync include/linux/fs.h:2750 [inline] dio_complete+0x763/0xac0 fs/direct-io.c:329 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #1 ((work_completion)(&dio->complete_work)){+.+.}: worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #0 ((wq_completion)"dio/%s"sb->s_id){+.+.}: flush_workqueue+0x117/0x13e0 kernel/workqueue.c:2661 drain_workqueue+0x1a5/0x460 kernel/workqueue.c:2826 destroy_workqueue+0x75/0x790 kernel/workqueue.c:4183 __alloc_workqueue_key+0xb76/0xed0 kernel/workqueue.c:4160 sb_init_dio_done_wq+0x34/0x90 fs/direct-io.c:623 do_blockdev_direct_IO fs/direct-io.c:1285 [inline] __blockdev_direct_IO+0x5f55/0xef40 fs/direct-io.c:1419 blockdev_direct_IO include/linux/fs.h:3059 [inline] fat_direct_IO+0x1d1/0x370 fs/fat/inode.c:282 generic_file_direct_write+0x208/0x4a0 mm/filemap.c:3073 __generic_file_write_iter+0x2d0/0x610 mm/filemap.c:3252 generic_file_write_iter+0x3f8/0x730 mm/filemap.c:3323 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 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: (wq_completion)"dio/%s"sb->s_id --> (work_completion)(&dio->complete_work) --> &sb->s_type->i_mutex_key#24 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#24); lock((work_completion)(&dio->complete_work)); lock(&sb->s_type->i_mutex_key#24); lock((wq_completion)"dio/%s"sb->s_id); *** DEADLOCK *** 1 lock held by syz-executor.2/14954: #0: 000000007579d4f4 (&sb->s_type->i_mutex_key#24){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000007579d4f4 (&sb->s_type->i_mutex_key#24){++++}, at: generic_file_write_iter+0x99/0x730 mm/filemap.c:3320 stack backtrace: CPU: 0 PID: 14954 Comm: syz-executor.2 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 flush_workqueue+0x117/0x13e0 kernel/workqueue.c:2661 drain_workqueue+0x1a5/0x460 kernel/workqueue.c:2826 destroy_workqueue+0x75/0x790 kernel/workqueue.c:4183 __alloc_workqueue_key+0xb76/0xed0 kernel/workqueue.c:4160 sb_init_dio_done_wq+0x34/0x90 fs/direct-io.c:623 do_blockdev_direct_IO fs/direct-io.c:1285 [inline] __blockdev_direct_IO+0x5f55/0xef40 fs/direct-io.c:1419 blockdev_direct_IO include/linux/fs.h:3059 [inline] fat_direct_IO+0x1d1/0x370 fs/fat/inode.c:282 generic_file_direct_write+0x208/0x4a0 mm/filemap.c:3073 __generic_file_write_iter+0x2d0/0x610 mm/filemap.c:3252 generic_file_write_iter+0x3f8/0x730 mm/filemap.c:3323 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 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fd933782669 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd9320f6168 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00007fd9338a3f80 RCX: 00007fd933782669 RDX: 0000000020000540 RSI: 0000000000001801 RDI: 00007fd93387f000 RBP: 00007fd9337dd560 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe4a2ec10f R14: 00007fd9320f6300 R15: 0000000000022000 autofs4:pid:15014:autofs_fill_super: called with bogus options overlayfs: unrecognized mount option "upperdir.d/bus" or missing value autofs4:pid:15088:autofs_fill_super: called with bogus options overlayfs: unrecognized mount option "upperdir.d/bus" or missing value overlayfs: unrecognized mount option "upperdir.d/bus" or missing value netlink: 5732 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 5732 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 5732 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 5732 bytes leftover after parsing attributes in process `syz-executor.4'. IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 overlayfs: './file0' not a directory overlayfs: './file0' not a directory audit: type=1800 audit(1664124492.773:618): pid=15595 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="file0" dev="sda1" ino=15009 res=0 audit: type=1804 audit(1664124492.793:619): pid=15595 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir2432914539/syzkaller.zhOWAi/574/file0" dev="sda1" ino=15009 res=1 audit: type=1800 audit(1664124493.663:620): pid=15639 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.5" name="file0" dev="sda1" ino=15021 res=0 audit: type=1804 audit(1664124493.663:621): pid=15640 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.5" name="/root/syzkaller-testdir2432914539/syzkaller.zhOWAi/575/file0" dev="sda1" ino=15021 res=1