BTRFS: device fsid 5ac8a51e-da3a-4998-8e66-e1df06b87bc8 devid 1 transid 8 /dev/loop1 scanned by syz-executor.1 (6194) ====================================================== WARNING: possible circular locking dependency detected 5.15.116-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/6194 is trying to acquire lock: ffff0000c08808b0 (&type->i_mutex_dir_key#2){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:797 [inline] ffff0000c08808b0 (&type->i_mutex_dir_key#2){++++}-{3:3}, at: lookup_slow+0x50/0x84 fs/namei.c:1675 but task is already holding lock: ffff0000fb0d8ce0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: btrfs_free_stale_devices+0x158/0x9ec fs/btrfs/volumes.c:603 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock_common+0x194/0x2154 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743 insert_dev_extents fs/btrfs/block-group.c:2345 [inline] btrfs_create_pending_block_groups+0x490/0xebc fs/btrfs/block-group.c:2395 __btrfs_end_transaction+0x13c/0x610 fs/btrfs/transaction.c:1007 btrfs_end_transaction+0x24/0x34 fs/btrfs/transaction.c:1043 find_free_extent_update_loop fs/btrfs/extent-tree.c:4044 [inline] find_free_extent+0x32b0/0x44c8 fs/btrfs/extent-tree.c:4393 btrfs_reserve_extent+0x1b4/0x43c fs/btrfs/extent-tree.c:4474 cow_file_range+0x4f0/0xb74 fs/btrfs/inode.c:1181 btrfs_run_delalloc_range+0x314/0x12cc fs/btrfs/inode.c:2018 writepage_delalloc+0x1d4/0x434 fs/btrfs/extent_io.c:3802 __extent_writepage+0x624/0xcbc fs/btrfs/extent_io.c:4108 extent_write_cache_pages fs/btrfs/extent_io.c:5029 [inline] extent_writepages+0x9b0/0x1268 fs/btrfs/extent_io.c:5156 btrfs_writepages+0x28/0x38 fs/btrfs/inode.c:8568 do_writepages+0x39c/0x5ec mm/page-writeback.c:2364 filemap_fdatawrite_wbc+0x1c8/0x228 mm/filemap.c:400 start_delalloc_inodes+0x630/0xa30 fs/btrfs/inode.c:10064 btrfs_start_delalloc_roots+0x5e4/0x898 fs/btrfs/inode.c:10143 shrink_delalloc fs/btrfs/space-info.c:538 [inline] flush_space+0x5b0/0xc94 fs/btrfs/space-info.c:646 btrfs_async_reclaim_metadata_space+0x6c8/0x80c fs/btrfs/space-info.c:953 process_one_work+0x790/0x11b8 kernel/workqueue.c:2307 worker_thread+0x910/0x1034 kernel/workqueue.c:2454 kthread+0x37c/0x45c kernel/kthread.c:319 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 -> #2 (sb_internal#3){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1742 [inline] sb_start_intwrite include/linux/fs.h:1859 [inline] start_transaction+0x644/0x1480 fs/btrfs/transaction.c:677 btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:790 btrfs_dirty_inode+0xb4/0x1c0 fs/btrfs/inode.c:6322 btrfs_update_time+0x248/0x270 fs/btrfs/inode.c:6364 inode_update_time fs/inode.c:1787 [inline] touch_atime+0x434/0xa4c fs/inode.c:1860 file_accessed include/linux/fs.h:2447 [inline] btrfs_file_mmap+0xb0/0x11c fs/btrfs/file.c:2424 call_mmap include/linux/fs.h:2108 [inline] mmap_region+0xcb4/0x12f0 mm/mmap.c:1791 do_mmap+0x6c0/0xcec mm/mmap.c:1575 vm_mmap_pgoff+0x1a4/0x2b4 mm/util.c:551 ksys_mmap_pgoff+0x458/0x668 mm/mmap.c:1624 __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline] __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline] __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> #1 (&mm->mmap_lock){++++}-{3:3}: __might_fault+0xc8/0x128 mm/memory.c:5311 filldir64+0x2bc/0x9e4 fs/readdir.c:335 dir_emit_dot include/linux/fs.h:3605 [inline] dir_emit_dots include/linux/fs.h:3616 [inline] dcache_readdir+0x134/0x678 fs/libfs.c:196 iterate_dir+0x1f4/0x4e4 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64 fs/readdir.c:354 [inline] __arm64_sys_getdents64+0x1c4/0x4c4 fs/readdir.c:354 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> #0 (&type->i_mutex_dir_key#2){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3787 [inline] __lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622 down_read+0xc0/0x398 kernel/locking/rwsem.c:1488 inode_lock_shared include/linux/fs.h:797 [inline] lookup_slow+0x50/0x84 fs/namei.c:1675 walk_component+0x394/0x4cc fs/namei.c:1972 lookup_last fs/namei.c:2427 [inline] path_lookupat+0x13c/0x3d0 fs/namei.c:2451 filename_lookup+0x1c4/0x4c8 fs/namei.c:2480 kern_path+0x4c/0x194 fs/namei.c:2570 lookup_bdev+0xc0/0x25c block/bdev.c:979 device_matched fs/btrfs/volumes.c:563 [inline] btrfs_free_stale_devices+0x61c/0x9ec fs/btrfs/volumes.c:608 btrfs_scan_one_device+0x438/0x5f8 fs/btrfs/volumes.c:1440 btrfs_mount_root+0x424/0x7f8 fs/btrfs/super.c:1716 legacy_get_tree+0xd4/0x16c fs/fs_context.c:610 vfs_get_tree+0x90/0x274 fs/super.c:1508 fc_mount fs/namespace.c:1000 [inline] vfs_kern_mount+0xdc/0x178 fs/namespace.c:1030 btrfs_mount+0x328/0x9b8 fs/btrfs/super.c:1812 legacy_get_tree+0xd4/0x16c fs/fs_context.c:610 vfs_get_tree+0x90/0x274 fs/super.c:1508 do_new_mount+0x25c/0x8c4 fs/namespace.c:2994 path_mount+0x590/0x104c fs/namespace.c:3324 do_mount fs/namespace.c:3337 [inline] __do_sys_mount fs/namespace.c:3545 [inline] __se_sys_mount fs/namespace.c:3522 [inline] __arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3522 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 other info that might help us debug this: Chain exists of: &type->i_mutex_dir_key#2 --> sb_internal#3 --> &fs_devs->device_list_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_devs->device_list_mutex); lock(sb_internal#3); lock(&fs_devs->device_list_mutex); lock(&type->i_mutex_dir_key#2); *** DEADLOCK *** 2 locks held by syz-executor.1/6194: #0: ffff800014f85468 (uuid_mutex){+.+.}-{3:3}, at: btrfs_mount_root+0x234/0x7f8 fs/btrfs/super.c:1709 #1: ffff0000fb0d8ce0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: btrfs_free_stale_devices+0x158/0x9ec fs/btrfs/volumes.c:603 stack backtrace: CPU: 1 PID: 6194 Comm: syz-executor.1 Not tainted 5.15.116-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011 check_noncircular+0x2cc/0x378 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 kernel/locking/lockdep.c:3787 [inline] __lock_acquire+0x32cc/0x7620 kernel/locking/lockdep.c:5011 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5622 down_read+0xc0/0x398 kernel/locking/rwsem.c:1488 inode_lock_shared include/linux/fs.h:797 [inline] lookup_slow+0x50/0x84 fs/namei.c:1675 walk_component+0x394/0x4cc fs/namei.c:1972 lookup_last fs/namei.c:2427 [inline] path_lookupat+0x13c/0x3d0 fs/namei.c:2451 filename_lookup+0x1c4/0x4c8 fs/namei.c:2480 kern_path+0x4c/0x194 fs/namei.c:2570 lookup_bdev+0xc0/0x25c block/bdev.c:979 device_matched fs/btrfs/volumes.c:563 [inline] btrfs_free_stale_devices+0x61c/0x9ec fs/btrfs/volumes.c:608 btrfs_scan_one_device+0x438/0x5f8 fs/btrfs/volumes.c:1440 btrfs_mount_root+0x424/0x7f8 fs/btrfs/super.c:1716 legacy_get_tree+0xd4/0x16c fs/fs_context.c:610 vfs_get_tree+0x90/0x274 fs/super.c:1508 fc_mount fs/namespace.c:1000 [inline] vfs_kern_mount+0xdc/0x178 fs/namespace.c:1030 btrfs_mount+0x328/0x9b8 fs/btrfs/super.c:1812 legacy_get_tree+0xd4/0x16c fs/fs_context.c:610 vfs_get_tree+0x90/0x274 fs/super.c:1508 do_new_mount+0x25c/0x8c4 fs/namespace.c:2994 path_mount+0x590/0x104c fs/namespace.c:3324 do_mount fs/namespace.c:3337 [inline] __do_sys_mount fs/namespace.c:3545 [inline] __se_sys_mount fs/namespace.c:3522 [inline] __arm64_sys_mount+0x510/0x5e0 fs/namespace.c:3522 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:596 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:614 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 BTRFS info (device loop1): using xxhash64 (xxhash64-generic) checksum algorithm BTRFS info (device loop1): using free space tree BTRFS info (device loop1): has skinny extents BTRFS info (device loop1): enabling ssd optimizations BTRFS info (device loop1): checking UUID tree