NILFS (loop6): vblocknr = 23 has abnormal lifetime: start cno (= 4294967298) > current cno (= 3) NILFS error (device loop6): nilfs_bmap_propagate: broken bmap (inode number=4) ====================================================== WARNING: possible circular locking dependency detected 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 Not tainted ------------------------------------------------------ segctord/8705 is trying to acquire lock: ffff8880586ba090 (&nilfs->ns_sem){++++}-{4:4}, at: nilfs_set_error fs/nilfs2/super.c:92 [inline] ffff8880586ba090 (&nilfs->ns_sem){++++}-{4:4}, at: __nilfs_error+0x1ca/0x4b0 fs/nilfs2/super.c:141 but task is already holding lock: ffff8880586ba2a0 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_lock+0x253/0x4c0 fs/nilfs2/segment.c:357 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&nilfs->ns_segctor_sem){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 down_read+0x46/0x2e0 kernel/locking/rwsem.c:1524 nilfs_transaction_begin+0x365/0x710 fs/nilfs2/segment.c:221 nilfs_ioctl_delete_checkpoint fs/nilfs2/ioctl.c:266 [inline] nilfs_ioctl+0x1505/0x24d0 fs/nilfs2/ioctl.c:1339 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (sb_internal#4){.+.+}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 percpu_down_read include/linux/percpu-rwsem.h:52 [inline] __sb_start_write include/linux/fs.h:1783 [inline] sb_start_intwrite include/linux/fs.h:1966 [inline] nilfs_transaction_begin+0x268/0x710 fs/nilfs2/segment.c:218 nilfs_page_mkwrite+0x8b0/0xc20 fs/nilfs2/file.c:95 do_page_mkwrite+0x14a/0x310 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing mm/memory.c:4160 [inline] handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x18d2/0x5380 mm/memory.c:6140 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6309 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1388 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x68/0x110 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #3 (sb_pagefaults#2){.+.+}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 percpu_down_read include/linux/percpu-rwsem.h:52 [inline] __sb_start_write include/linux/fs.h:1783 [inline] sb_start_pagefault include/linux/fs.h:1948 [inline] nilfs_page_mkwrite+0x21e/0xc20 fs/nilfs2/file.c:57 do_page_mkwrite+0x14a/0x310 mm/memory.c:3287 do_shared_fault mm/memory.c:5594 [inline] do_fault mm/memory.c:5656 [inline] do_pte_missing mm/memory.c:4160 [inline] handle_pte_fault mm/memory.c:5997 [inline] __handle_mm_fault+0x18d2/0x5380 mm/memory.c:6140 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6309 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1388 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x68/0x110 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #2 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __might_fault+0xcc/0x130 mm/memory.c:7151 _copy_to_iter+0xf3/0x15a0 lib/iov_iter.c:184 copy_page_to_iter+0xa7/0x150 lib/iov_iter.c:362 copy_folio_to_iter include/linux/uio.h:198 [inline] filemap_read+0x78d/0x11d0 mm/filemap.c:2753 blkdev_read_iter+0x30a/0x440 block/fops.c:809 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4cd/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&sb->s_type->i_mutex_key#7){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 inode_lock include/linux/fs.h:867 [inline] set_blocksize+0x23b/0x500 block/bdev.c:203 sb_set_blocksize block/bdev.c:224 [inline] sb_min_blocksize+0x119/0x210 block/bdev.c:239 init_nilfs+0x43/0x690 fs/nilfs2/the_nilfs.c:710 nilfs_fill_super+0x8f/0x650 fs/nilfs2/super.c:1060 nilfs_get_tree+0x4f4/0x870 fs/nilfs2/super.c:1228 vfs_get_tree+0x8f/0x2b0 fs/super.c:1759 do_new_mount+0x24a/0xa40 fs/namespace.c:3884 do_mount fs/namespace.c:4224 [inline] __do_sys_mount fs/namespace.c:4435 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4412 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&nilfs->ns_sem){++++}-{4:4}: check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3909 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 nilfs_set_error fs/nilfs2/super.c:92 [inline] __nilfs_error+0x1ca/0x4b0 fs/nilfs2/super.c:141 nilfs_bmap_convert_error fs/nilfs2/bmap.c:35 [inline] nilfs_bmap_propagate+0x108/0x130 fs/nilfs2/bmap.c:332 nilfs_collect_file_data+0x4f/0xd0 fs/nilfs2/segment.c:589 nilfs_segctor_apply_buffers+0x161/0x330 fs/nilfs2/segment.c:1010 nilfs_segctor_scan_file+0x68e/0x8e0 fs/nilfs2/segment.c:1059 nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1254 [inline] nilfs_segctor_collect fs/nilfs2/segment.c:1547 [inline] nilfs_segctor_do_construct+0x1d46/0x6970 fs/nilfs2/segment.c:2122 nilfs_segctor_construct+0x17b/0x690 fs/nilfs2/segment.c:2478 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2586 [inline] nilfs_segctor_thread+0x6f7/0xe00 fs/nilfs2/segment.c:2700 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Chain exists of: &nilfs->ns_sem --> sb_internal#4 --> &nilfs->ns_segctor_sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&nilfs->ns_segctor_sem); lock(sb_internal#4); lock(&nilfs->ns_segctor_sem); lock(&nilfs->ns_sem); *** DEADLOCK *** 1 lock held by segctord/8705: #0: ffff8880586ba2a0 (&nilfs->ns_segctor_sem){++++}-{4:4}, at: nilfs_transaction_lock+0x253/0x4c0 fs/nilfs2/segment.c:357 stack backtrace: CPU: 1 UID: 0 PID: 8705 Comm: segctord Not tainted 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2079 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2211 check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3909 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 nilfs_set_error fs/nilfs2/super.c:92 [inline] __nilfs_error+0x1ca/0x4b0 fs/nilfs2/super.c:141 nilfs_bmap_convert_error fs/nilfs2/bmap.c:35 [inline] nilfs_bmap_propagate+0x108/0x130 fs/nilfs2/bmap.c:332 nilfs_collect_file_data+0x4f/0xd0 fs/nilfs2/segment.c:589 nilfs_segctor_apply_buffers+0x161/0x330 fs/nilfs2/segment.c:1010 nilfs_segctor_scan_file+0x68e/0x8e0 fs/nilfs2/segment.c:1059 nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1254 [inline] nilfs_segctor_collect fs/nilfs2/segment.c:1547 [inline] nilfs_segctor_do_construct+0x1d46/0x6970 fs/nilfs2/segment.c:2122 nilfs_segctor_construct+0x17b/0x690 fs/nilfs2/segment.c:2478 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2586 [inline] nilfs_segctor_thread+0x6f7/0xe00 fs/nilfs2/segment.c:2700 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Remounting filesystem read-only