====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.2047/14810 is trying to acquire lock: ffff888077a250c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ffff888077a250c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1902 but task is already holding lock: ffff88807cbb0c58 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1768 [inline] ffff88807cbb0c58 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1a4/0x350 fs/ext4/inode.c:2808 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_down_read fs/ext4/ext4.h:1768 [inline] ext4_writepages+0x1a4/0x350 fs/ext4/inode.c:2808 do_writepages+0x351/0x590 mm/page-writeback.c:2575 __writeback_single_inode+0x14e/0xee0 fs/fs-writeback.c:1635 writeback_single_inode+0x21f/0x760 fs/fs-writeback.c:1756 write_inode_now+0x183/0x210 fs/fs-writeback.c:2808 iput_final fs/inode.c:1807 [inline] iput+0x58f/0x900 fs/inode.c:1846 ext4_xattr_block_set+0x248b/0x2fe0 fs/ext4/xattr.c:2201 ext4_xattr_move_to_block fs/ext4/xattr.c:2666 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2741 [inline] ext4_expand_extra_isize_ea+0x128f/0x1e70 fs/ext4/xattr.c:2829 __ext4_expand_extra_isize+0x306/0x400 fs/ext4/inode.c:5990 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6033 [inline] __ext4_mark_inode_dirty+0x458/0x6d0 fs/ext4/inode.c:6111 ext4_evict_inode+0x7dd/0xe70 fs/ext4/inode.c:254 evict+0x4b7/0x8a0 fs/inode.c:705 ext4_orphan_cleanup+0xc33/0x1470 fs/ext4/orphan.c:472 __ext4_fill_super fs/ext4/super.c:5621 [inline] ext4_fill_super+0x5fb5/0x6870 fs/ext4/super.c:5744 get_tree_bdev+0x3e5/0x520 fs/super.c:1591 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24a/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 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:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 down_write+0x97/0x200 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1902 ext4_do_writepages+0x4f2/0x3990 fs/ext4/inode.c:2606 ext4_writepages+0x1dd/0x350 fs/ext4/inode.c:2809 do_writepages+0x351/0x590 mm/page-writeback.c:2575 filemap_fdatawrite_wbc+0x122/0x180 mm/filemap.c:390 __filemap_fdatawrite_range mm/filemap.c:423 [inline] __filemap_fdatawrite mm/filemap.c:429 [inline] filemap_flush+0xe4/0x150 mm/filemap.c:456 ext4_convert_inline_data+0x18a/0x5b0 fs/ext4/inline.c:2069 ext4_page_mkwrite+0x219/0x11a0 fs/ext4/inode.c:6265 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 wp_page_shared mm/memory.c:3311 [inline] do_wp_page+0xd4d/0x34d0 mm/memory.c:3396 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1306/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 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 *** 4 locks held by syz.2.2047/14810: #0: ffff88807db8cda0 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff88807db8cda0 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff88807db8cda0 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5440 #1: ffff888058d90510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff888058d90510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff888058d90510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1e2/0x11a0 fs/ext4/inode.c:6260 #2: ffff888077a255a0 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:859 [inline] #2: ffff888077a255a0 (mapping.invalidate_lock#2){++++}-{3:3}, at: ext4_page_mkwrite+0x20c/0x11a0 fs/ext4/inode.c:6263 #3: ffff88807cbb0c58 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1768 [inline] #3: ffff88807cbb0c58 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1a4/0x350 fs/ext4/inode.c:2808 stack backtrace: CPU: 0 PID: 14810 Comm: syz.2.2047 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x37ef/0x7d80 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 down_write+0x97/0x200 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline] ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1902 ext4_do_writepages+0x4f2/0x3990 fs/ext4/inode.c:2606 ext4_writepages+0x1dd/0x350 fs/ext4/inode.c:2809 do_writepages+0x351/0x590 mm/page-writeback.c:2575 filemap_fdatawrite_wbc+0x122/0x180 mm/filemap.c:390 __filemap_fdatawrite_range mm/filemap.c:423 [inline] __filemap_fdatawrite mm/filemap.c:429 [inline] filemap_flush+0xe4/0x150 mm/filemap.c:456 ext4_convert_inline_data+0x18a/0x5b0 fs/ext4/inline.c:2069 ext4_page_mkwrite+0x219/0x11a0 fs/ext4/inode.c:6265 do_page_mkwrite+0x153/0x3f0 mm/memory.c:2951 wp_page_shared mm/memory.c:3311 [inline] do_wp_page+0xd4d/0x34d0 mm/memory.c:3396 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x1306/0x4a50 mm/memory.c:5353 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371 handle_page_fault arch/x86/mm/fault.c:1463 [inline] exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f7d3c96cd22 Code: 1f 84 00 00 00 00 00 90 83 fa 10 73 2d 83 fa 08 73 46 83 fa 04 73 16 83 fa 01 7c 10 8a 0e 74 0a 0f b7 74 16 fe 66 89 74 17 fe <88> 0f c3 8b 4c 16 fc 8b 36 89 4c 17 fc 89 37 c3 c5 fa 6f 06 c5 fa RSP: 002b:00007ffc664623a8 EFLAGS: 00010246 RAX: 0000200000000280 RBX: 0000000000000004 RCX: 0000000000000007 RDX: 0000000000000001 RSI: 0000001b2cd208d6 RDI: 0000200000000280 RBP: fffffffffffffffe R08: 0000001b2d120000 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000000 R12: 00007ffc664624d0 R13: 00007f7d3cc25fac R14: 00000000000ceff2 R15: 00007f7d3cc25fa0