====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ kworker/u8:12/27491 is trying to acquire lock: ffff888077978600 (sb_internal#2){.+.+}-{0:0}, at: btrfs_finish_one_ordered+0x88e/0x2680 fs/btrfs/inode.c:3254 but task is already holding lock: ffff88803966a758 (btrfs_ordered_extent){++++}-{0:0}, at: btrfs_finish_one_ordered+0x39c/0x2680 fs/btrfs/inode.c:3216 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #8 (btrfs_ordered_extent){++++}-{0:0}: btrfs_start_ordered_extent_nowriteback+0x390/0x700 fs/btrfs/ordered-data.c:890 btrfs_start_ordered_extent fs/btrfs/ordered-data.h:203 [inline] btrfs_wait_ordered_range+0x154/0x260 fs/btrfs/ordered-data.c:942 btrfs_sync_file+0x78a/0x1200 fs/btrfs/file.c:1662 generic_write_sync include/linux/fs.h:2654 [inline] btrfs_do_write_iter+0x6a3/0x840 fs/btrfs/file.c:1468 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #7 (&ei->i_mmap_lock){++++}-{4:4}: down_read+0x47/0x2e0 kernel/locking/rwsem.c:1568 btrfs_page_mkwrite+0x636/0x1a60 fs/btrfs/file.c:1918 do_page_mkwrite+0x14d/0x310 mm/memory.c:3668 wp_page_shared mm/memory.c:4069 [inline] do_wp_page+0x19ba/0x4cc0 mm/memory.c:4288 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault mm/memory.c:6549 [inline] handle_mm_fault+0x151d/0x3170 mm/memory.c:6718 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 -> #6 (sb_pagefaults#3){.+.+}-{0:0}: percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_pagefault include/linux/fs/super.h:159 [inline] btrfs_page_mkwrite+0x351/0x1a60 fs/btrfs/file.c:1873 do_page_mkwrite+0x14d/0x310 mm/memory.c:3668 wp_page_shared mm/memory.c:4069 [inline] do_wp_page+0x19ba/0x4cc0 mm/memory.c:4288 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault mm/memory.c:6549 [inline] handle_mm_fault+0x151d/0x3170 mm/memory.c:6718 do_user_addr_fault+0x75b/0x1340 arch/x86/mm/fault.c:1385 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline] _inline_copy_to_user include/linux/uaccess.h:206 [inline] _copy_to_user+0x85/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:236 [inline] do_pipe2+0xd4/0x190 fs/pipe.c:1040 __do_sys_pipe fs/pipe.c:1061 [inline] __se_sys_pipe fs/pipe.c:1059 [inline] __x64_sys_pipe+0x3a/0x50 fs/pipe.c:1059 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (&mm->mmap_lock){++++}-{4:4}: down_write_killable+0xa6/0x240 kernel/locking/rwsem.c:1637 mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline] upgrade_mmap_lock_carefully+0xba/0x1b0 mm/mmap_lock.c:474 lock_mm_and_find_vma+0x12b/0x340 mm/mmap_lock.c:527 do_user_addr_fault+0x330/0x1340 arch/x86/mm/fault.c:1357 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 filldir64+0x2b2/0x640 fs/readdir.c:368 dir_emit include/linux/fs.h:3578 [inline] offset_dir_emit fs/libfs.c:499 [inline] offset_iterate_dir fs/libfs.c:515 [inline] offset_readdir+0x3fc/0x530 fs/libfs.c:564 iterate_dir+0x399/0x570 fs/readdir.c:110 __do_sys_getdents64 fs/readdir.c:399 [inline] __se_sys_getdents64+0xf1/0x280 fs/readdir.c:384 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&type->i_mutex_dir_key#5){++++}-{4:4}: down_read+0x47/0x2e0 kernel/locking/rwsem.c:1568 inode_lock_shared include/linux/fs.h:1044 [inline] lookup_slow+0x46/0x70 fs/namei.c:1931 walk_component fs/namei.c:2278 [inline] lookup_last fs/namei.c:2785 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2809 filename_lookup+0x256/0x5d0 fs/namei.c:2838 kern_path+0x3d/0x150 fs/namei.c:3044 is_same_device fs/btrfs/volumes.c:764 [inline] device_list_add+0xfd1/0x2280 fs/btrfs/volumes.c:898 btrfs_scan_one_device+0x3ef/0x680 fs/btrfs/volumes.c:1499 btrfs_get_tree_super fs/btrfs/super.c:1858 [inline] btrfs_get_tree_subvol fs/btrfs/super.c:2087 [inline] btrfs_get_tree+0x4ab/0x1910 fs/btrfs/super.c:2121 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3758 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3834 do_mount fs/namespace.c:4167 [inline] __do_sys_mount fs/namespace.c:4383 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4360 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (&fs_devs->device_list_mutex){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:632 [inline] __mutex_lock+0x1a3/0x1550 kernel/locking/mutex.c:806 insert_dev_extents fs/btrfs/block-group.c:2876 [inline] btrfs_create_pending_block_groups+0x77b/0x1b40 fs/btrfs/block-group.c:2927 __btrfs_end_transaction+0x140/0x650 fs/btrfs/transaction.c:1091 flush_space+0x406/0xe20 fs/btrfs/space-info.c:912 do_async_reclaim_data_space+0x145/0x520 fs/btrfs/space-info.c:1448 btrfs_async_reclaim_data_space+0x41/0x90 fs/btrfs/space-info.c:1512 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}: join_transaction+0x192/0xe40 fs/btrfs/transaction.c:324 start_transaction+0xbef/0x1820 fs/btrfs/transaction.c:719 btrfs_dirty_inode+0x9f/0x190 fs/btrfs/inode.c:6441 touch_atime+0x2f8/0x6b0 fs/inode.c:2265 file_accessed include/linux/fs.h:2264 [inline] filemap_read+0x1053/0x1230 mm/filemap.c:2878 __kernel_read+0x504/0x9b0 fs/read_write.c:532 integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:222 [inline] ima_calc_file_hash+0x446/0x860 security/integrity/ima/ima_crypto.c:280 ima_collect_measurement+0x51d/0x9c0 security/integrity/ima/ima_api.c:300 process_measurement+0x12cd/0x1c80 security/integrity/ima/ima_main.c:425 ima_file_check+0xe1/0x130 security/integrity/ima/ima_main.c:685 security_file_post_open+0xb3/0x260 security/security.c:2755 do_open fs/namei.c:4701 [inline] path_openat+0x2e4d/0x3860 fs/namei.c:4858 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1381 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (btrfs_trans_num_writers){++++}-{0:0}: join_transaction+0x171/0xe40 fs/btrfs/transaction.c:323 start_transaction+0xbef/0x1820 fs/btrfs/transaction.c:719 btrfs_dirty_inode+0x9f/0x190 fs/btrfs/inode.c:6441 touch_atime+0x2f8/0x6b0 fs/inode.c:2265 file_accessed include/linux/fs.h:2264 [inline] filemap_read+0x1053/0x1230 mm/filemap.c:2878 __kernel_read+0x504/0x9b0 fs/read_write.c:532 integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:222 [inline] ima_calc_file_hash+0x446/0x860 security/integrity/ima/ima_crypto.c:280 ima_collect_measurement+0x51d/0x9c0 security/integrity/ima/ima_api.c:300 process_measurement+0x12cd/0x1c80 security/integrity/ima/ima_main.c:425 ima_file_check+0xe1/0x130 security/integrity/ima/ima_main.c:685 security_file_post_open+0xb3/0x260 security/security.c:2755 do_open fs/namei.c:4701 [inline] path_openat+0x2e4d/0x3860 fs/namei.c:4858 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1381 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sb_internal#2){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_intwrite include/linux/fs/super.h:177 [inline] start_transaction+0xaa9/0x1820 fs/btrfs/transaction.c:713 btrfs_finish_one_ordered+0x88e/0x2680 fs/btrfs/inode.c:3254 btrfs_work_helper+0x37b/0xc20 fs/btrfs/async-thread.c:312 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Chain exists of: sb_internal#2 --> &ei->i_mmap_lock --> btrfs_ordered_extent Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(btrfs_ordered_extent); lock(&ei->i_mmap_lock); lock(btrfs_ordered_extent); rlock(sb_internal#2); *** DEADLOCK *** 3 locks held by kworker/u8:12/27491: #0: ffff88807c47f940 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88807c47f940 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90006627c40 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90006627c40 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 #2: ffff88803966a758 (btrfs_ordered_extent){++++}-{0:0}, at: btrfs_finish_one_ordered+0x39c/0x2680 fs/btrfs/inode.c:3216 stack backtrace: CPU: 1 UID: 0 PID: 27491 Comm: kworker/u8:12 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Workqueue: btrfs-endio-write btrfs_work_helper Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs/super.h:19 [inline] sb_start_intwrite include/linux/fs/super.h:177 [inline] start_transaction+0xaa9/0x1820 fs/btrfs/transaction.c:713 btrfs_finish_one_ordered+0x88e/0x2680 fs/btrfs/inode.c:3254 btrfs_work_helper+0x37b/0xc20 fs/btrfs/async-thread.c:312 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245