====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.327/6821 is trying to acquire lock: ffff888060fd8ac8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ffff888060fd8ac8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1884 but task is already holding lock: ffff88802ec76bd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1767 [inline] ffff88802ec76bd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x170/0x2f0 fs/ext4/inode.c:2806 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:1767 [inline] ext4_writepages+0x170/0x2f0 fs/ext4/inode.c:2806 do_writepages+0x3a2/0x600 mm/page-writeback.c:2575 __writeback_single_inode+0x153/0xee0 fs/fs-writeback.c:1635 writeback_single_inode+0x211/0x720 fs/fs-writeback.c:1756 write_inode_now+0x161/0x1e0 fs/fs-writeback.c:2802 iput_final fs/inode.c:1807 [inline] iput+0x5b2/0x920 fs/inode.c:1846 ext4_xattr_block_set+0x273a/0x32a0 fs/ext4/xattr.c:2211 ext4_xattr_move_to_block fs/ext4/xattr.c:2679 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2754 [inline] ext4_expand_extra_isize_ea+0x10ea/0x19e0 fs/ext4/xattr.c:2846 __ext4_expand_extra_isize+0x306/0x400 fs/ext4/inode.c:5967 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6010 [inline] __ext4_mark_inode_dirty+0x45d/0x6e0 fs/ext4/inode.c:6088 ext4_evict_inode+0x7ed/0xea0 fs/ext4/inode.c:252 evict+0x486/0x870 fs/inode.c:705 ext4_orphan_cleanup+0xbd4/0x1400 fs/ext4/orphan.c:470 __ext4_fill_super fs/ext4/super.c:5601 [inline] ext4_fill_super+0x5de4/0x66c0 fs/ext4/super.c:5724 get_tree_bdev+0x3e4/0x510 fs/super.c:1591 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 down_write+0x97/0x1f0 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1884 ext4_do_writepages+0x4c2/0x38d0 fs/ext4/inode.c:2604 ext4_writepages+0x1a8/0x2f0 fs/ext4/inode.c:2807 do_writepages+0x3a2/0x600 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+0xc5/0x120 mm/filemap.c:456 ext4_convert_inline_data+0x181/0x5e0 fs/ext4/inline.c:2051 ext4_page_mkwrite+0x20e/0x1210 fs/ext4/inode.c:6242 do_page_mkwrite+0x153/0x3e0 mm/memory.c:2951 wp_page_shared mm/memory.c:3311 [inline] do_wp_page+0xe5e/0x3630 mm/memory.c:3396 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x12d4/0x4920 mm/memory.c:5353 do_user_addr_fault+0x738/0x12e0 arch/x86/mm/fault.c:1373 handle_page_fault arch/x86/mm/fault.c:1465 [inline] exc_page_fault+0x67/0x110 arch/x86/mm/fault.c:1521 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.0.327/6821: #0: ffff88807e71baa0 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:165 [inline] #0: ffff88807e71baa0 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5380 [inline] #0: ffff88807e71baa0 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x300 mm/memory.c:5440 #1: ffff88802ec74510 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1633 [inline] #1: ffff88802ec74510 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1737 [inline] #1: ffff88802ec74510 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1dc/0x1210 fs/ext4/inode.c:6237 #2: ffff888060fd8fa0 (mapping.invalidate_lock#2){++++}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:859 [inline] #2: ffff888060fd8fa0 (mapping.invalidate_lock#2){++++}-{3:3}, at: ext4_page_mkwrite+0x206/0x1210 fs/ext4/inode.c:6240 #3: ffff88802ec76bd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1767 [inline] #3: ffff88802ec76bd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x170/0x2f0 fs/ext4/inode.c:2806 stack backtrace: CPU: 1 PID: 6821 Comm: syz.0.327 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 check_noncircular+0x2bd/0x3c0 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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 down_write+0x97/0x1f0 kernel/locking/rwsem.c:1573 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x28/0xe0 fs/ext4/inline.c:1884 ext4_do_writepages+0x4c2/0x38d0 fs/ext4/inode.c:2604 ext4_writepages+0x1a8/0x2f0 fs/ext4/inode.c:2807 do_writepages+0x3a2/0x600 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+0xc5/0x120 mm/filemap.c:456 ext4_convert_inline_data+0x181/0x5e0 fs/ext4/inline.c:2051 ext4_page_mkwrite+0x20e/0x1210 fs/ext4/inode.c:6242 do_page_mkwrite+0x153/0x3e0 mm/memory.c:2951 wp_page_shared mm/memory.c:3311 [inline] do_wp_page+0xe5e/0x3630 mm/memory.c:3396 handle_pte_fault mm/memory.c:5063 [inline] __handle_mm_fault mm/memory.c:5188 [inline] handle_mm_fault+0x12d4/0x4920 mm/memory.c:5353 do_user_addr_fault+0x738/0x12e0 arch/x86/mm/fault.c:1373 handle_page_fault arch/x86/mm/fault.c:1465 [inline] exc_page_fault+0x67/0x110 arch/x86/mm/fault.c:1521 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7fde166655b9 Code: ff ff ff 01 64 48 8b 04 25 00 00 00 00 48 8d b8 c8 fe ff ff e8 f8 5f 0c 00 85 c0 75 10 48 8b 44 24 68 48 8b b4 24 98 00 00 00 <48> 89 30 64 f0 83 2c 25 90 ff ff ff 01 48 8b 84 24 80 00 00 00 48 RSP: 002b:00007ffed3dcf770 EFLAGS: 00010246 RAX: 0000200000000140 RBX: 0000000000000002 RCX: ffffffffffffedff RDX: 4041b701383287a1 RSI: 0000200000001200 RDI: 00005555935aa3c8 RBP: 00007fde169e7da0 R08: 0000001b2d820000 R09: 0000000000000048 R10: 0000000000000000 R11: 0000000000000001 R12: 00007fde169e5fac R13: 00007ffed3dcf860 R14: fffffffffffffffe R15: 00007ffed3dcf880 EXT4-fs (loop0): Delayed block allocation failed for inode 15 at logical offset 0 with max blocks 1 with error 28 EXT4-fs (loop0): This should not happen!! Data will be lost EXT4-fs (loop0): Total free blocks count 0 EXT4-fs (loop0): Free/Dirty block details EXT4-fs (loop0): free_blocks=2415919104 EXT4-fs (loop0): dirty_blocks=32 EXT4-fs (loop0): Block reservation details EXT4-fs (loop0): i_reserved_data_blocks=2