====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.9.686/8895 is trying to acquire lock: ffff888061525088 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ffff888061525088 (&ei->xattr_sem){++++}-{3:3}, at: ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1890 but task is already holding lock: ffff88805febcbd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1c0/0x2d20 fs/ext4/inode.c:2689 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+0x46/0x1b0 include/linux/percpu-rwsem.h:51 ext4_writepages+0x1c0/0x2d20 fs/ext4/inode.c:2689 do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386 __writeback_single_inode+0x153/0xda0 fs/fs-writeback.c:1657 writeback_single_inode+0x221/0x8b0 fs/fs-writeback.c:1770 write_inode_now+0x217/0x280 fs/fs-writeback.c:2811 iput_final fs/inode.c:1756 [inline] iput+0x5ab/0x8a0 fs/inode.c:1795 ext4_xattr_set_entry+0x10ff/0x3d30 fs/ext4/xattr.c:1837 ext4_xattr_block_set+0x4f7/0x2d30 fs/ext4/xattr.c:1936 ext4_xattr_move_to_block fs/ext4/xattr.c:2633 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2708 [inline] ext4_expand_extra_isize_ea+0xf4b/0x19a0 fs/ext4/xattr.c:2800 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:5901 ext4_try_to_expand_extra_isize fs/ext4/inode.c:5944 [inline] __ext4_mark_inode_dirty+0x469/0x700 fs/ext4/inode.c:6022 ext4_evict_inode+0xa81/0x1080 fs/ext4/inode.c:282 evict+0x485/0x870 fs/inode.c:647 ext4_orphan_cleanup+0xaa9/0x12e0 fs/ext4/orphan.c:470 ext4_fill_super+0x92f0/0x9a60 fs/ext4/super.c:4975 mount_bdev+0x287/0x3c0 fs/super.c:1400 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3562 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #0 (&ei->xattr_sem){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1890 ext4_writepages+0x5df/0x2d20 fs/ext4/inode.c:2735 do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] file_write_and_wait_range+0x129/0x1e0 mm/filemap.c:810 ext4_sync_file+0x1ff/0xae0 fs/ext4/fsync.c:151 generic_write_sync include/linux/fs.h:2990 [inline] ext4_buffered_write_iter+0x338/0x3b0 fs/ext4/file.c:275 ext4_file_write_iter+0x773/0x17b0 fs/ext4/file.c:-1 __kernel_write+0x4f9/0x930 fs/read_write.c:539 __dump_emit+0x243/0x360 fs/coredump.c:943 elf_core_dump+0x29e8/0x3530 fs/binfmt_elf.c:2264 do_coredump+0x1419/0x2960 fs/coredump.c:894 get_signal+0x40a/0x12c0 kernel/signal.c:2886 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1504 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 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.9.686/8895: #0: ffff888068ee8460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x13fd/0x2960 fs/coredump.c:893 #1: ffff88805febcbd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1c0/0x2d20 fs/ext4/inode.c:2689 stack backtrace: CPU: 1 PID: 8895 Comm: syz.9.686 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 down_write+0x38/0x60 kernel/locking/rwsem.c:1551 ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline] ext4_destroy_inline_data+0x24/0xe0 fs/ext4/inline.c:1890 ext4_writepages+0x5df/0x2d20 fs/ext4/inode.c:2735 do_writepages+0x48d/0x6d0 mm/page-writeback.c:2386 filemap_fdatawrite_wbc+0x1eb/0x240 mm/filemap.c:400 __filemap_fdatawrite_range mm/filemap.c:433 [inline] file_write_and_wait_range+0x129/0x1e0 mm/filemap.c:810 ext4_sync_file+0x1ff/0xae0 fs/ext4/fsync.c:151 generic_write_sync include/linux/fs.h:2990 [inline] ext4_buffered_write_iter+0x338/0x3b0 fs/ext4/file.c:275 ext4_file_write_iter+0x773/0x17b0 fs/ext4/file.c:-1 __kernel_write+0x4f9/0x930 fs/read_write.c:539 __dump_emit+0x243/0x360 fs/coredump.c:943 elf_core_dump+0x29e8/0x3530 fs/binfmt_elf.c:2264 do_coredump+0x1419/0x2960 fs/coredump.c:894 get_signal+0x40a/0x12c0 kernel/signal.c:2886 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1504 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7f5a6da346b7 Code: 88 15 42 60 ec 00 88 05 3f 60 ec 00 c3 50 48 8d 35 e9 48 1c 00 48 8d 3d ef 48 1c 00 31 c0 e8 20 f7 ff ff 53 89 fb 48 83 ec 10 <64> 8b 04 25 94 ff ff ff 85 c0 74 2a 89 fe 31 c0 bf 3c 00 00 00 e8 RSP: 002b:00007f5a6bd9b120 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f5a6db74749 RDX: 00007f5a6bd9b140 RSI: 00007f5a6bd9b270 RDI: 000000000000000b RBP: 00007f5a6dbf8f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f5a6ddcb128 R14: 00007f5a6ddcb090 R15: 00007ffd7f95a398 EXT4-fs (loop9): Delayed block allocation failed for inode 19 at logical offset 0 with max blocks 1 with error 28