Hello, syzbot found the following issue on: HEAD commit: bbed346d5a96 Merge branch 'for-next/core' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=12497f8a880000 kernel config: https://syzkaller.appspot.com/x/.config?x=3a4a45d2d827c1e dashboard link: https://syzkaller.appspot.com/bug?extid=3a94da2c82ba4f401b9e compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/e8e91bc79312/disk-bbed346d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c1cb3fb3b77e/vmlinux-bbed346d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3a94da2c82ba4f401b9e@xxxxxxxxxxxxxxxxxxxxxxxxx WARNING: possible circular locking dependency detected 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Not tainted ------------------------------------------------------ syz-executor.5/28633 is trying to acquire lock: ffff0001126ee890 (&nilfs->ns_sem){++++}-{3:3}, at: nilfs_set_error fs/nilfs2/super.c:92 [inline] ffff0001126ee890 (&nilfs->ns_sem){++++}-{3:3}, at: __nilfs_error+0xb4/0x284 fs/nilfs2/super.c:137 but task is already holding lock: ffff000123b51e70 (&dat_lock_key ){.+.+}-{3:3}, at: nilfs_get_block+0x64/0x364 fs/nilfs2/inode.c:84 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&dat_lock_key){.+.+}-{3:3}: down_read+0x5c/0x78 kernel/locking/rwsem.c:1499 nilfs_count_free_blocks+0x2c/0x6c fs/nilfs2/the_nilfs.c:693 nilfs_set_log_cursor fs/nilfs2/super.c:236 [inline] nilfs_cleanup_super+0x118/0x1f0 fs/nilfs2/super.c:318 nilfs_put_super+0x54/0x9c fs/nilfs2/super.c:472 generic_shutdown_super+0x8c/0x190 fs/super.c:491 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xe8 fs/super.c:332 deactivate_super+0xd0/0xd4 fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x14c kernel/task_work.c:177 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x174/0x1f0 arch/arm64/kernel/signal.c:1127 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x150 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 -> #0 (&nilfs->ns_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:3829 [inline] __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666 down_write+0x5c/0xcc kernel/locking/rwsem.c:1552 nilfs_set_error fs/nilfs2/super.c:92 [inline] __nilfs_error+0xb4/0x284 fs/nilfs2/super.c:137 nilfs_bmap_convert_error fs/nilfs2/bmap.c:35 [inline] nilfs_bmap_lookup_contig+0x98/0xc0 fs/nilfs2/bmap.c:95 nilfs_get_block+0x7c/0x364 fs/nilfs2/inode.c:85 block_truncate_page+0x1b4/0xab4 fs/buffer.c:2583 nilfs_truncate+0xb8/0x178 fs/nilfs2/inode.c:857 nilfs_setattr+0xf8/0x164 fs/nilfs2/inode.c:955 notify_change+0x758/0x7f0 fs/attr.c:420 do_truncate+0x108/0x150 fs/open.c:65 vfs_truncate+0x1dc/0x24c fs/open.c:111 do_sys_truncate+0x94/0x140 fs/open.c:134 __do_sys_truncate fs/open.c:146 [inline] __se_sys_truncate fs/open.c:144 [inline] __arm64_sys_truncate+0x20/0x30 fs/open.c:144 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&dat_lock_key); lock(&nilfs->ns_sem); lock(&dat_lock_key); lock(&nilfs->ns_sem); *** DEADLOCK *** 5 locks held by syz-executor.5/28633: #0: ffff0001199e2460 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x20/0x64 fs/namespace.c:393 #1: ffff0001128b2648 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] #1: ffff0001128b2648 (&sb->s_type->i_mutex_key#26){+.+.}-{3:3}, at: do_truncate+0xf4/0x150 fs/open.c:63 #2: ffff0001199e2650 (sb_internal#3){.+.+}-{0:0}, at: nilfs_setattr+0x84/0x164 fs/nilfs2/inode.c:947 #3: ffff0001126eeaa0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_begin+0x214/0x384 fs/nilfs2/segment.c:223 #4: ffff000123b51e70 (&dat_lock_key){.+.+}-{3:3}, at: nilfs_get_block+0x64/0x364 fs/nilfs2/inode.c:84 stack backtrace: CPU: 1 PID: 28633 Comm: syz-executor.5 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/30/2022 Call trace: dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:156 show_stack+0x2c/0x54 arch/arm64/kernel/stacktrace.c:163 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x104/0x16c lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 print_circular_bug+0x2c4/0x2c8 kernel/locking/lockdep.c:2053 check_noncircular+0x14c/0x154 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3095 [inline] check_prevs_add kernel/locking/lockdep.c:3214 [inline] validate_chain kernel/locking/lockdep.c:3829 [inline] __lock_acquire+0x1530/0x30a4 kernel/locking/lockdep.c:5053 lock_acquire+0x100/0x1f8 kernel/locking/lockdep.c:5666 down_write+0x5c/0xcc kernel/locking/rwsem.c:1552 nilfs_set_error fs/nilfs2/super.c:92 [inline] __nilfs_error+0xb4/0x284 fs/nilfs2/super.c:137 nilfs_bmap_convert_error fs/nilfs2/bmap.c:35 [inline] nilfs_bmap_lookup_contig+0x98/0xc0 fs/nilfs2/bmap.c:95 nilfs_get_block+0x7c/0x364 fs/nilfs2/inode.c:85 block_truncate_page+0x1b4/0xab4 fs/buffer.c:2583 nilfs_truncate+0xb8/0x178 fs/nilfs2/inode.c:857 nilfs_setattr+0xf8/0x164 fs/nilfs2/inode.c:955 notify_change+0x758/0x7f0 fs/attr.c:420 do_truncate+0x108/0x150 fs/open.c:65 vfs_truncate+0x1dc/0x24c fs/open.c:111 do_sys_truncate+0x94/0x140 fs/open.c:134 __do_sys_truncate fs/open.c:146 [inline] __se_sys_truncate fs/open.c:144 [inline] __arm64_sys_truncate+0x20/0x30 fs/open.c:144 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 Remounting filesystem read-only NILFS (loop5): bad btree node (ino=16, blocknr=15): level = 0, flags = 0x0, nchildren = 0 NILFS error (device loop5): nilfs_bmap_last_key: broken bmap (inode number=16) NILFS (loop5): error -5 truncating bmap (ino=16) --- This report is generated by a bot. 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