====================================================== WARNING: possible circular locking dependency detected 5.15.176-syzkaller #0 Not tainted ------------------------------------------------------ syz.5.629/7290 is trying to acquire lock: ffff88802560e650 (sb_internal#2){.+.+}-{0:0}, at: btrfs_dirty_inode+0xcc/0x1c0 fs/btrfs/inode.c:6436 but task is already holding lock: ffff888025481628 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] ffff888025481628 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x175/0x2d0 mm/util.c:549 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mm->mmap_lock){++++}-{3:3}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498 mmap_read_lock+0x1c/0x50 include/linux/mmap_lock.h:117 do_user_addr_fault arch/x86/mm/fault.c:1308 [inline] handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x596/0x700 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 __get_user_nocheck_1+0x6/0x10 arch/x86/lib/getuser.S:103 fault_in_readable+0x172/0x2e0 mm/gup.c:1801 fault_in_iov_iter_readable+0x14a/0x1d0 lib/iov_iter.c:460 generic_perform_write+0x1c9/0x5b0 mm/filemap.c:3775 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944 do_iter_readv_writev+0x594/0x7a0 do_iter_write+0x1e6/0x760 fs/read_write.c:855 vfs_writev fs/read_write.c:928 [inline] do_pwritev+0x219/0x360 fs/read_write.c:1025 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #2 (&sb->s_type->i_mutex_key#27){++++}-{3:3}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 down_read+0x45/0x2e0 kernel/locking/rwsem.c:1498 inode_lock_shared include/linux/fs.h:799 [inline] lookup_slow+0x45/0x70 fs/namei.c:1679 walk_component+0x48c/0x610 fs/namei.c:1976 lookup_last fs/namei.c:2431 [inline] path_lookupat+0x16f/0x450 fs/namei.c:2455 filename_lookup+0x230/0x5c0 fs/namei.c:2484 kern_path+0x37/0x180 fs/namei.c:2582 lookup_bdev+0xc1/0x280 block/bdev.c:979 device_matched fs/btrfs/volumes.c:568 [inline] btrfs_free_stale_devices+0x71f/0xb00 fs/btrfs/volumes.c:608 btrfs_forget_devices+0x52/0x80 fs/btrfs/volumes.c:1431 btrfs_control_ioctl+0x108/0x210 fs/btrfs/super.c:2451 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #1 (&fs_devs->device_list_mutex){+.+.}-{3:3}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 insert_dev_extents fs/btrfs/block-group.c:2395 [inline] btrfs_create_pending_block_groups+0x5c1/0x1130 fs/btrfs/block-group.c:2445 __btrfs_end_transaction+0x296/0x780 fs/btrfs/transaction.c:1014 flush_space+0x4cf/0xd50 fs/btrfs/space-info.c:674 btrfs_async_reclaim_data_space+0x118/0x3e0 fs/btrfs/space-info.c:1169 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 -> #0 (sb_internal#2){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1813 [inline] sb_start_intwrite include/linux/fs.h:1930 [inline] start_transaction+0x5a8/0x11a0 fs/btrfs/transaction.c:678 btrfs_dirty_inode+0xcc/0x1c0 fs/btrfs/inode.c:6436 inode_update_time fs/inode.c:1868 [inline] touch_atime+0x34e/0x680 fs/inode.c:1941 file_accessed include/linux/fs.h:2523 [inline] btrfs_file_mmap+0xbf/0x120 fs/btrfs/file.c:2451 call_mmap include/linux/fs.h:2179 [inline] mmap_file+0x5a/0xb0 mm/util.c:1092 __mmap_region mm/mmap.c:1784 [inline] mmap_region+0x1035/0x1870 mm/mmap.c:2921 do_mmap+0x78d/0xe00 mm/mmap.c:1574 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:551 ksys_mmap_pgoff+0x559/0x780 mm/mmap.c:1623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Chain exists of: sb_internal#2 --> &sb->s_type->i_mutex_key#27 --> &mm->mmap_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_lock); lock(&sb->s_type->i_mutex_key#27); lock(&mm->mmap_lock); lock(sb_internal#2); *** DEADLOCK *** 2 locks held by syz.5.629/7290: #0: ffff888025481628 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline] #0: ffff888025481628 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x175/0x2d0 mm/util.c:549 #1: ffff88802560e460 (sb_writers#14){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2523 [inline] #1: ffff88802560e460 (sb_writers#14){.+.+}-{0:0}, at: btrfs_file_mmap+0xbf/0x120 fs/btrfs/file.c:2451 stack backtrace: CPU: 1 PID: 7290 Comm: syz.5.629 Not tainted 5.15.176-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1813 [inline] sb_start_intwrite include/linux/fs.h:1930 [inline] start_transaction+0x5a8/0x11a0 fs/btrfs/transaction.c:678 btrfs_dirty_inode+0xcc/0x1c0 fs/btrfs/inode.c:6436 inode_update_time fs/inode.c:1868 [inline] touch_atime+0x34e/0x680 fs/inode.c:1941 file_accessed include/linux/fs.h:2523 [inline] btrfs_file_mmap+0xbf/0x120 fs/btrfs/file.c:2451 call_mmap include/linux/fs.h:2179 [inline] mmap_file+0x5a/0xb0 mm/util.c:1092 __mmap_region mm/mmap.c:1784 [inline] mmap_region+0x1035/0x1870 mm/mmap.c:2921 do_mmap+0x78d/0xe00 mm/mmap.c:1574 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:551 ksys_mmap_pgoff+0x559/0x780 mm/mmap.c:1623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f4a7aa04d29 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4a78833038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f4a7abf5160 RCX: 00007f4a7aa04d29 RDX: 000000000000000a RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007f4a7aa80b08 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000028011 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f4a7abf5160 R15: 00007ffd1db11698