NILFS (loop4): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/8159 is trying to acquire lock: 0000000041d699f8 (&dat_lock_key){.+.+}, at: nilfs_count_free_blocks+0x68/0x180 fs/nilfs2/the_nilfs.c:698 but task is already holding lock: 0000000058286f68 (&nilfs->ns_sem){++++}, at: nilfs_put_super+0x14a/0x1a0 fs/nilfs2/super.c:472 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&nilfs->ns_sem){++++}: nilfs_set_error fs/nilfs2/super.c:86 [inline] __nilfs_error+0x195/0x401 fs/nilfs2/super.c:131 nilfs_ifile_get_inode_block+0x12a/0x170 fs/nilfs2/ifile.c:139 __nilfs_read_inode fs/nilfs2/inode.c:483 [inline] nilfs_iget+0x204/0x860 fs/nilfs2/inode.c:592 nilfs_lookup fs/nilfs2/namei.c:63 [inline] nilfs_lookup+0xfd/0x130 fs/nilfs2/namei.c:54 lookup_open+0x698/0x1a20 fs/namei.c:3214 do_last fs/namei.c:3327 [inline] path_openat+0x1804/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&dat_lock_key){.+.+}: down_read+0x36/0x80 kernel/locking/rwsem.c:24 nilfs_count_free_blocks+0x68/0x180 fs/nilfs2/the_nilfs.c:698 nilfs_set_log_cursor fs/nilfs2/super.c:237 [inline] nilfs_cleanup_super+0x133/0x490 fs/nilfs2/super.c:319 nilfs_put_super+0x152/0x1a0 fs/nilfs2/super.c:473 generic_shutdown_super+0x144/0x370 fs/super.c:456 kill_block_super+0x97/0xf0 fs/super.c:1185 deactivate_locked_super+0x94/0x160 fs/super.c:329 deactivate_super+0x174/0x1a0 fs/super.c:360 cleanup_mnt+0x1a8/0x290 fs/namespace.c:1098 task_work_run+0x148/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&nilfs->ns_sem); lock(&dat_lock_key); lock(&nilfs->ns_sem); lock(&dat_lock_key); *** DEADLOCK *** 2 locks held by syz-executor.4/8159: #0: 00000000a57f92df (&type->s_umount_key#95){+.+.}, at: deactivate_super+0x16c/0x1a0 fs/super.c:359 #1: 0000000058286f68 (&nilfs->ns_sem){++++}, at: nilfs_put_super+0x14a/0x1a0 fs/nilfs2/super.c:472 stack backtrace: CPU: 1 PID: 8159 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 down_read+0x36/0x80 kernel/locking/rwsem.c:24 nilfs_count_free_blocks+0x68/0x180 fs/nilfs2/the_nilfs.c:698 nilfs_set_log_cursor fs/nilfs2/super.c:237 [inline] nilfs_cleanup_super+0x133/0x490 fs/nilfs2/super.c:319 nilfs_put_super+0x152/0x1a0 fs/nilfs2/super.c:473 generic_shutdown_super+0x144/0x370 fs/super.c:456 kill_block_super+0x97/0xf0 fs/super.c:1185 deactivate_locked_super+0x94/0x160 fs/super.c:329 deactivate_super+0x174/0x1a0 fs/super.c:360 cleanup_mnt+0x1a8/0x290 fs/namespace.c:1098 task_work_run+0x148/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f87a2a5d517 Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe47273448 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f87a2a5d517 RDX: 00007ffe4727351b RSI: 000000000000000a RDI: 00007ffe47273510 RBP: 00007ffe47273510 R08: 00000000ffffffff R09: 00007ffe472732e0 R10: 0000555557057903 R11: 0000000000000246 R12: 00007f87a2ab6b24 R13: 00007ffe472745d0 R14: 0000555557057810 R15: 00007ffe47274610 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'. IPVS: ftp: loaded support on port[0] = 21 NILFS (loop4): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'. IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 NILFS (loop4): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds NILFS (loop4): segctord starting. Construction interval = 5 seconds, CP frequency < 30 seconds IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.1'. IPVS: ftp: loaded support on port[0] = 21 team0: Port device geneve2 added