EXT4-fs error (device loop2): ext4_mb_generate_buddy:1147: group 0, block bitmap and bg descriptor inconsistent: 25 vs 281 free clusters ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.37/4469 is trying to acquire lock: ffff888073f1c690 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ffff888073f1c690 (&ei->xattr_sem){++++}-{3:3}, at: ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1890 but task is already holding lock: ffff888077290bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1c0/0x2d20 fs/ext4/inode.c:2689 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 ( &sbi->s_writepages_rwsem ){.+.+}-{0:0} : percpu_down_read+0x46/0x1b0 include/linux/percpu-rwsem.h:51 ext4_writepages+0x1c0/0x2d20 fs/ext4/inode.c:2689 do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386 __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657 writeback_single_inode+0x221/0x8b0 fs/fs-writeback.c:1770 write_inode_now+0x217/0x280 fs/fs-writeback.c:2811 iput_final fs/inode.c:1756 [inline] iput+0x5ab/0x8a0 fs/inode.c:1795 ext4_xattr_set_entry+0x10ff/0x3d30 fs/ext4/xattr.c:1837 ext4_xattr_block_set+0x4f7/0x2d30 fs/ext4/xattr.c:1936 ext4_xattr_move_to_block fs/ext4/xattr.c:2633 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2708 [inline] ext4_expand_extra_isize_ea+0xf4b/0x19a0 fs/ext4/xattr.c:2800 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5901 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5944 [inline] __ext4_mark_inode_dirty+0x469/0x700 fs/ext4/inode.c:6022 ext4_evict_inode+0xa81/0x1080 fs/ext4/inode.c:282 evict+0x485/0x870 fs/inode.c:647 ext4_orphan_cleanup+0xaa9/0x12e0 fs/ext4/orphan.c:470 ext4_fill_super+0x92f0/0x9a60 fs/ext4/super.c:4975 mount_bdev+0x287/0x3c0 fs/super.c:1400 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3562 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&ei->xattr_sem){++++}-{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:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1890 ext4_writepages+0x5df/0x2d20 fs/ext4/inode.c:2735 do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] file_write_and_wait_range+0x129/0x1e0 mm/filemap.c:810 ext4_sync_file+0x1ff/0xae0 fs/ext4/fsync.c:151 generic_write_sync include/linux/fs.h:2990 [inline] ext4_buffered_write_iter+0x338/0x3b0 fs/ext4/file.c:275 ext4_file_write_iter+0x773/0x17b0 fs/ext4/file.c:-1 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_pwrite64 fs/read_write.c:701 [inline] __do_sys_pwrite64 fs/read_write.c:711 [inline] __se_sys_pwrite64 fs/read_write.c:708 [inline] __x64_sys_pwrite64+0x194/0x220 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); *** DEADLOCK *** 2 locks held by syz.2.37/4469: #0: ffff88802c2b2460 (sb_writers#5){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590 #1: ffff888077290bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1c0/0x2d20 fs/ext4/inode.c:2689 stack backtrace: CPU: 1 PID: 4469 Comm: syz.2.37 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 check_noncircular+0x274/0x310 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:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1890 ext4_writepages+0x5df/0x2d20 fs/ext4/inode.c:2735 do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] file_write_and_wait_range+0x129/0x1e0 mm/filemap.c:810 ext4_sync_file+0x1ff/0xae0 fs/ext4/fsync.c:151 generic_write_sync include/linux/fs.h:2990 [inline] ext4_buffered_write_iter+0x338/0x3b0 fs/ext4/file.c:275 ext4_file_write_iter+0x773/0x17b0 fs/ext4/file.c:-1 call_write_iter include/linux/fs.h:2173 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x712/0xd00 fs/read_write.c:594 ksys_pwrite64 fs/read_write.c:701 [inline] __do_sys_pwrite64 fs/read_write.c:711 [inline] __se_sys_pwrite64 fs/read_write.c:708 [inline] __x64_sys_pwrite64+0x194/0x220 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fbd6d2396c9 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:00007fbd6b47f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007fbd6d490090 RCX: 00007fbd6d2396c9 RDX: 0000000000000086 RSI: 0000200000000280 RDI: 0000000000000006 RBP: 00007fbd6d2bbf91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fbd6d490128 R14: 00007fbd6d490090 R15: 00007ffe9c899a28 EXT4-fs (loop2): Delayed block allocation failed for inode 15 at logical offset 0 with max blocks 1 with error 28 EXT4-fs (loop2): This should not happen!! Data will be lost EXT4-fs (loop2): Total free blocks count 0 EXT4-fs (loop2): Free/Dirty block details EXT4-fs (loop2): free_blocks=4112 EXT4-fs (loop2): dirty_blocks=16 EXT4-fs (loop2): Block reservation details EXT4-fs (loop2): i_reserved_data_blocks=1