EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.6.3595/21849 is trying to acquire lock: ffff88805c656108 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline] ffff88805c656108 (&ei->xattr_sem){++++}-{4:4}, at: ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1797 but task is already holding lock: ffff888078fb2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline] ffff888078fb2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1820 [inline] ffff888078fb2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1ca/0x350 fs/ext4/inode.c:3025 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_internal+0x48/0x1c0 include/linux/percpu-rwsem.h:53 percpu_down_read include/linux/percpu-rwsem.h:77 [inline] ext4_writepages_down_read fs/ext4/ext4.h:1820 [inline] ext4_writepages+0x1ca/0x350 fs/ext4/inode.c:3025 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 __writeback_single_inode+0x133/0x1070 fs/fs-writeback.c:1750 writeback_single_inode+0x493/0xc70 fs/fs-writeback.c:1869 write_inode_now+0x160/0x1d0 fs/fs-writeback.c:2952 iput_final fs/inode.c:1946 [inline] iput+0x8c1/0xe80 fs/inode.c:2005 ext4_xattr_block_set+0x1fce/0x2ac0 fs/ext4/xattr.c:2204 ext4_xattr_move_to_block fs/ext4/xattr.c:2669 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2744 [inline] ext4_expand_extra_isize_ea+0x12da/0x1ea0 fs/ext4/xattr.c:2832 __ext4_expand_extra_isize+0x30d/0x400 fs/ext4/inode.c:6348 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6391 [inline] __ext4_mark_inode_dirty+0x45c/0x6e0 fs/ext4/inode.c:6469 ext4_evict_inode+0x79c/0xe60 fs/ext4/inode.c:253 evict+0x5f4/0xae0 fs/inode.c:837 ext4_orphan_cleanup+0xc20/0x1460 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5665 [inline] ext4_fill_super+0x58bb/0x6170 fs/ext4/super.c:5784 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691 vfs_get_tree+0x92/0x2a0 fs/super.c:1751 fc_mount fs/namespace.c:1204 [inline] do_new_mount_fc fs/namespace.c:3763 [inline] do_new_mount+0x31a/0xcf0 fs/namespace.c:3839 do_mount fs/namespace.c:4162 [inline] __do_sys_mount fs/namespace.c:4351 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4328 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&ei->xattr_sem){++++}-{4:4}: 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+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1590 ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline] ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1797 ext4_do_writepages+0x4e6/0x4500 fs/ext4/inode.c:2811 ext4_writepages+0x203/0x350 fs/ext4/inode.c:3026 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 filemap_writeback mm/filemap.c:387 [inline] filemap_flush_range mm/filemap.c:436 [inline] filemap_flush+0x191/0x230 mm/filemap.c:451 ext4_convert_inline_data+0x180/0x5e0 fs/ext4/inline.c:1964 ext4_fallocate+0x1e2/0x3d0 fs/ext4/extents.c:4824 vfs_fallocate+0x669/0x7e0 fs/open.c:340 ioctl_preallocate fs/ioctl.c:289 [inline] file_ioctl+0x611/0x780 fs/ioctl.c:-1 do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:576 __do_sys_ioctl fs/ioctl.c:595 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); lock(&sbi->s_writepages_rwsem); lock(&ei->xattr_sem); *** DEADLOCK *** 3 locks held by syz.6.3595/21849: #0: ffff888078fb4420 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2705 [inline] #0: ffff888078fb4420 (sb_writers#4){.+.+}-{0:0}, at: vfs_fallocate+0x5f0/0x7e0 fs/open.c:339 #1: ffff88805c656420 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline] #1: ffff88805c656420 (&sb->s_type->i_mutex_key#11){++++}-{4:4}, at: ext4_fallocate+0x1da/0x3d0 fs/ext4/extents.c:4823 #2: ffff888078fb2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline] #2: ffff888078fb2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1820 [inline] #2: ffff888078fb2b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1ca/0x350 fs/ext4/inode.c:3025 stack backtrace: CPU: 1 UID: 0 PID: 21849 Comm: syz.6.3595 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e2/0x300 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+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1590 ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline] ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1797 ext4_do_writepages+0x4e6/0x4500 fs/ext4/inode.c:2811 ext4_writepages+0x203/0x350 fs/ext4/inode.c:3026 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 filemap_writeback mm/filemap.c:387 [inline] filemap_flush_range mm/filemap.c:436 [inline] filemap_flush+0x191/0x230 mm/filemap.c:451 ext4_convert_inline_data+0x180/0x5e0 fs/ext4/inline.c:1964 ext4_fallocate+0x1e2/0x3d0 fs/ext4/extents.c:4824 vfs_fallocate+0x669/0x7e0 fs/open.c:340 ioctl_preallocate fs/ioctl.c:289 [inline] file_ioctl+0x611/0x780 fs/ioctl.c:-1 do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:576 __do_sys_ioctl fs/ioctl.c:595 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f752998f749 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:00007f7527bf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f7529be5fa0 RCX: 00007f752998f749 RDX: 0000200000000240 RSI: 0000000040305829 RDI: 0000000000000005 RBP: 00007f7529a13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7529be6038 R14: 00007f7529be5fa0 R15: 00007ffcde742318 EXT4-fs error (device loop6): ext4_mb_generate_buddy:1306: group 0, block bitmap and bg descriptor inconsistent: 0 vs 150994969 free clusters EXT4-fs (loop6): Delayed block allocation failed for inode 15 at logical offset 0 with max blocks 1 with error 28 EXT4-fs (loop6): This should not happen!! Data will be lost EXT4-fs (loop6): Total free blocks count 0 EXT4-fs (loop6): Free/Dirty block details EXT4-fs (loop6): free_blocks=2415919504 EXT4-fs (loop6): dirty_blocks=32 EXT4-fs (loop6): Block reservation details EXT4-fs (loop6): i_reserved_data_blocks=2