====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.118/6718 is trying to acquire lock: ffff88805e5200b8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_write_lock_xattr fs/ext4/xattr.h:157 [inline] ffff88805e5200b8 (&ei->xattr_sem){++++}-{4:4}, at: ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1805 but task is already holding lock: ffff888066e64cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline] ffff888066e64cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1814 [inline] ffff888066e64cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3028 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+0x48/0x1d0 include/linux/percpu-rwsem.h:53 percpu_down_read include/linux/percpu-rwsem.h:77 [inline] ext4_writepages_down_read fs/ext4/ext4.h:1814 [inline] ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3028 do_writepages+0x32e/0x550 mm/page-writeback.c:2575 __writeback_single_inode+0x133/0x11a0 fs/fs-writeback.c:1762 writeback_single_inode+0x488/0xd60 fs/fs-writeback.c:1881 write_inode_now+0x1c2/0x290 fs/fs-writeback.c:2972 iput_final fs/inode.c:1956 [inline] iput+0x8c1/0xe80 fs/inode.c:2015 ext4_xattr_block_set+0x1fd4/0x2ad0 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+0x12cf/0x1ea0 fs/ext4/xattr.c:2832 __ext4_expand_extra_isize+0x30d/0x400 fs/ext4/inode.c:6342 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6385 [inline] __ext4_mark_inode_dirty+0x45c/0x730 fs/ext4/inode.c:6463 ext4_evict_inode+0x8c9/0x1040 fs/ext4/inode.c:265 evict+0x61e/0xb10 fs/inode.c:846 ext4_orphan_cleanup+0xc38/0x1470 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5693 [inline] ext4_fill_super+0x59bb/0x62d0 fs/ext4/super.c:5816 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3763 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3839 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4338 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/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+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868 down_write+0x3a/0x50 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:1805 ext4_do_writepages+0x521/0x46e0 fs/ext4/inode.c:2814 ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3029 do_writepages+0x32e/0x550 mm/page-writeback.c:2575 filemap_writeback mm/filemap.c:387 [inline] filemap_fdatawrite_range mm/filemap.c:412 [inline] file_write_and_wait_range+0x374/0x440 mm/filemap.c:786 generic_buffers_fsync_noflush+0x73/0x1d0 fs/buffer.c:606 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline] ext4_sync_file+0x424/0xdb0 fs/ext4/fsync.c:159 generic_write_sync include/linux/fs.h:2640 [inline] ext4_buffered_write_iter+0x2ce/0x3a0 fs/ext4/file.c:306 ext4_file_write_iter+0x299/0x1c10 fs/ext4/file.c:-1 iter_file_splice_write+0x9a6/0x10f0 fs/splice.c:736 do_splice_from fs/splice.c:936 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1159 splice_direct_to_actor+0x545/0xc80 fs/splice.c:1103 do_splice_direct_actor fs/splice.c:1202 [inline] do_splice_direct+0x19b/0x2a0 fs/splice.c:1228 vfs_copy_file_range+0xb20/0x1390 fs/read_write.c:1634 __do_sys_copy_file_range fs/read_write.c:1683 [inline] __se_sys_copy_file_range+0x2fb/0x480 fs/read_write.c:1650 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/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 *** 2 locks held by syz.2.118/6718: #0: ffff888063840480 (sb_writers#4){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1158 #1: ffff888066e64cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline] #1: ffff888066e64cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1814 [inline] #1: ffff888066e64cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3028 stack backtrace: CPU: 1 UID: 0 PID: 6718 Comm: syz.2.118 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 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+0xf0/0x2e0 kernel/locking/lockdep.c:5868 down_write+0x3a/0x50 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:1805 ext4_do_writepages+0x521/0x46e0 fs/ext4/inode.c:2814 ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3029 do_writepages+0x32e/0x550 mm/page-writeback.c:2575 filemap_writeback mm/filemap.c:387 [inline] filemap_fdatawrite_range mm/filemap.c:412 [inline] file_write_and_wait_range+0x374/0x440 mm/filemap.c:786 generic_buffers_fsync_noflush+0x73/0x1d0 fs/buffer.c:606 ext4_fsync_nojournal fs/ext4/fsync.c:92 [inline] ext4_sync_file+0x424/0xdb0 fs/ext4/fsync.c:159 generic_write_sync include/linux/fs.h:2640 [inline] ext4_buffered_write_iter+0x2ce/0x3a0 fs/ext4/file.c:306 ext4_file_write_iter+0x299/0x1c10 fs/ext4/file.c:-1 iter_file_splice_write+0x9a6/0x10f0 fs/splice.c:736 do_splice_from fs/splice.c:936 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1159 splice_direct_to_actor+0x545/0xc80 fs/splice.c:1103 do_splice_direct_actor fs/splice.c:1202 [inline] do_splice_direct+0x19b/0x2a0 fs/splice.c:1228 vfs_copy_file_range+0xb20/0x1390 fs/read_write.c:1634 __do_sys_copy_file_range fs/read_write.c:1683 [inline] __se_sys_copy_file_range+0x2fb/0x480 fs/read_write.c:1650 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48860fc819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4884356028 EFLAGS: 00000246 ORIG_RAX: 0000000000000146 RAX: ffffffffffffffda RBX: 00007f4886375fa0 RCX: 00007f48860fc819 RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007f4886192c91 R08: 0000000000000863 R09: 0000000000000000 R10: 00002000000000c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4886376038 R14: 00007f4886375fa0 R15: 00007ffdd41dda98 EXT4-fs error (device loop2): ext4_mb_generate_buddy:1317: group 0, block bitmap and bg descriptor inconsistent: 25 vs 4128793 free clusters EXT4-fs (loop2): Delayed block allocation failed for inode 15 at logical offset 30 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=66060288 EXT4-fs (loop2): dirty_blocks=32 EXT4-fs (loop2): Block reservation details EXT4-fs (loop2): i_reserved_data_blocks=2 EXT4-fs (loop2): Delayed block allocation failed for inode 15 at logical offset 0 with max blocks 1 with error 28