====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.7.359/6175 is trying to acquire lock: ffff8880508ab2f0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ffff8880508ab2f0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1930 but task is already holding lock: ffff88802659ec18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717 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+0x44/0x1a0 include/linux/percpu-rwsem.h:51 ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717 do_writepages+0x3c6/0x640 mm/page-writeback.c:2491 __writeback_single_inode+0x153/0x1170 fs/fs-writeback.c:1622 writeback_single_inode+0x3d2/0x8e0 fs/fs-writeback.c:1743 write_inode_now+0x17f/0x210 fs/fs-writeback.c:2786 iput_final fs/inode.c:1821 [inline] iput+0x643/0x9c0 fs/inode.c:1860 ext4_xattr_block_set+0x2224/0x2fe0 fs/ext4/xattr.c:2095 ext4_xattr_move_to_block fs/ext4/xattr.c:2613 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2688 [inline] ext4_expand_extra_isize_ea+0xfca/0x1d40 fs/ext4/xattr.c:2776 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:6003 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6046 [inline] __ext4_mark_inode_dirty+0x478/0x760 fs/ext4/inode.c:6124 ext4_evict_inode+0xa67/0x10e0 fs/ext4/inode.c:281 evict+0x4b6/0x8b0 fs/inode.c:705 ext4_orphan_cleanup+0xc32/0x1470 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5574 [inline] ext4_fill_super+0x6f0c/0x78f0 fs/ext4/super.c:5693 get_tree_bdev+0x3e6/0x610 fs/super.c:1366 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x247/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&ei->xattr_sem){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2d18/0x7c40 kernel/locking/lockdep.c:5063 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 down_write+0x36/0x60 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1930 ext4_writepages+0x599/0x2e70 fs/ext4/inode.c:2763 do_writepages+0x3c6/0x640 mm/page-writeback.c:2491 filemap_fdatawrite_wbc+0x11e/0x180 mm/filemap.c:388 __filemap_fdatawrite_range mm/filemap.c:421 [inline] file_write_and_wait_range+0x159/0x230 mm/filemap.c:774 ext4_sync_file+0x22a/0xc30 fs/ext4/fsync.c:151 generic_write_sync include/linux/fs.h:2962 [inline] ext4_buffered_write_iter+0x2de/0x380 fs/ext4/file.c:292 ext4_file_write_iter+0x1e3/0x17d0 fs/ext4/file.c:-1 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x482/0x9a0 fs/read_write.c:584 ksys_pwrite64 fs/read_write.c:699 [inline] __do_sys_pwrite64 fs/read_write.c:709 [inline] __se_sys_pwrite64 fs/read_write.c:706 [inline] __x64_sys_pwrite64+0x194/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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.7.359/6175: #0: ffff88802659c460 (sb_writers#4){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580 #1: ffff88802659ec18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717 stack backtrace: CPU: 1 PID: 6175 Comm: syz.7.359 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3830 [inline] __lock_acquire+0x2d18/0x7c40 kernel/locking/lockdep.c:5063 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5676 down_write+0x36/0x60 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1930 ext4_writepages+0x599/0x2e70 fs/ext4/inode.c:2763 do_writepages+0x3c6/0x640 mm/page-writeback.c:2491 filemap_fdatawrite_wbc+0x11e/0x180 mm/filemap.c:388 __filemap_fdatawrite_range mm/filemap.c:421 [inline] file_write_and_wait_range+0x159/0x230 mm/filemap.c:774 ext4_sync_file+0x22a/0xc30 fs/ext4/fsync.c:151 generic_write_sync include/linux/fs.h:2962 [inline] ext4_buffered_write_iter+0x2de/0x380 fs/ext4/file.c:292 ext4_file_write_iter+0x1e3/0x17d0 fs/ext4/file.c:-1 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x482/0x9a0 fs/read_write.c:584 ksys_pwrite64 fs/read_write.c:699 [inline] __do_sys_pwrite64 fs/read_write.c:709 [inline] __se_sys_pwrite64 fs/read_write.c:706 [inline] __x64_sys_pwrite64+0x194/0x220 fs/read_write.c:706 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f62ef59de59 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:00007f62f0422028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007f62ef825fa0 RCX: 00007f62ef59de59 RDX: 000000000000fdef RSI: 0000200000000140 RDI: 0000000000000004 RBP: 00007f62ef633e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000e7c R11: 0000000000000246 R12: 0000000000000000 R13: 00007f62ef826038 R14: 00007f62ef825fa0 R15: 00007ffe67e9cc38 EXT4-fs error (device loop7): ext4_validate_block_bitmap:438: comm syz.7.359: bg 0: block 465: padding at end of block bitmap is not set EXT4-fs (loop7): Remounting filesystem read-only