BUG: MAX_LOCKDEP_CHAINS too low!

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: f6e27dbb Linux 4.14.146
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1769c783600000
kernel config: https://syzkaller.appspot.com/x/.config?x=cb75afefe94a0801
dashboard link: https://syzkaller.appspot.com/bug?extid=e28bdba98daaea0c87af
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+e28bdb...@syzkaller.appspotmail.com

BUG: MAX_LOCKDEP_CHAINS too low!
turning off the locking correctness validator.
CPU: 0 PID: 1432 Comm: syz-executor.4 Not tainted 4.14.146 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x138/0x197 lib/dump_stack.c:53
add_chain_cache kernel/locking/lockdep.c:2299 [inline]
lookup_chain_cache_add kernel/locking/lockdep.c:2411 [inline]
validate_chain kernel/locking/lockdep.c:2431 [inline]
__lock_acquire.cold+0x2dd/0x8dc kernel/locking/lockdep.c:3487
lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3991
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:152
spin_lock include/linux/spinlock.h:317 [inline]
find_inode_nowait+0x6c/0x180 fs/inode.c:1364
ext4_update_other_inodes_time fs/ext4/inode.c:5042 [inline]
ext4_do_update_inode fs/ext4/inode.c:5166 [inline]
ext4_mark_iloc_dirty+0x1f8b/0x2900 fs/ext4/inode.c:5706
ext4_mark_inode_dirty+0x1f0/0x860 fs/ext4/inode.c:5885
ext4_dirty_inode+0x73/0xa0 fs/ext4/inode.c:5916
__mark_inode_dirty+0x54c/0x1040 fs/fs-writeback.c:2141
mark_inode_dirty include/linux/fs.h:2019 [inline]
ext4_setattr+0x9f4/0x2270 fs/ext4/inode.c:5505
notify_change+0x8d1/0xd10 fs/attr.c:313
ovl_set_timestamps+0xdf/0x120 fs/overlayfs/copy_up.c:208
ovl_do_copy_up fs/overlayfs/copy_up.c:580 [inline]
ovl_copy_up_one+0x7c6/0x8d0 fs/overlayfs/copy_up.c:637
ovl_copy_up_flags+0xdd/0x130 fs/overlayfs/copy_up.c:685
ovl_copy_up+0x18/0x1c fs/overlayfs/copy_up.c:697
ovl_rename+0x219/0xeb0 fs/overlayfs/dir.c:947
vfs_rename+0x551/0x17d0 fs/namei.c:4493
SYSC_renameat2 fs/namei.c:4641 [inline]
SyS_renameat2+0x8c9/0xa30 fs/namei.c:4530
do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x459a29
RSP: 002b:00007fd6dfd34c78 EFLAGS: 00000246 ORIG_RAX: 000000000000013c
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459a29
RDX: 0000000000000004 RSI: 0000000020000000 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000002 R09: 0000000000000000
R10: 00000000200001c0 R11: 0000000000000246 R12: 00007fd6dfd356d4
R13: 00000000004c6fd5 R14: 00000000004dc660 R15: 00000000ffffffff
overlayfs: filesystem on './file0' not supported as upperdir
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'ip6gre5' (ffff888017699170): kobject_add_internal: parent: 'net',
set: 'devices'
kobject: 'ip6gre5' (ffff888017699170): kobject_uevent_env
kobject: 'ip6gre5' (ffff888017699170): fill_kobj_path: path
= '/devices/virtual/net/ip6gre5'
kobject: 'queues' (ffff888054dedb48): kobject_add_internal:
parent: 'ip6gre5', set: '<NULL>'
kobject: 'queues' (ffff888054dedb48): kobject_uevent_env
kobject: 'queues' (ffff888054dedb48): kobject_uevent_env: filter function
caused the event to drop!
kobject: 'rx-0' (ffff88809eb67b50): kobject_add_internal: parent: 'queues',
set: 'queues'
kobject: 'rx-0' (ffff88809eb67b50): kobject_uevent_env
kobject: 'rx-0' (ffff88809eb67b50): fill_kobj_path: path
= '/devices/virtual/net/ip6gre5/queues/rx-0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'tx-0' (ffff88803aef17d8): kobject_add_internal: parent: 'queues',
set: 'queues'
kobject: 'tx-0' (ffff88803aef17d8): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'tx-0' (ffff88803aef17d8): fill_kobj_path: path
= '/devices/virtual/net/ip6gre5/queues/tx-0'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
caif:caif_disconnect_client(): nothing to disconnect
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
caif:caif_disconnect_client(): nothing to disconnect
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
caif:caif_disconnect_client(): nothing to disconnect
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
caif:caif_disconnect_client(): nothing to disconnect
XFS (loop0): Invalid superblock magic number
caif:caif_disconnect_client(): nothing to disconnect
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
caif:caif_disconnect_client(): nothing to disconnect
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
caif:caif_disconnect_client(): nothing to disconnect
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
XFS (loop0): Invalid superblock magic number
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
caif:caif_disconnect_client(): nothing to disconnect
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
XFS (loop0): Invalid superblock magic number
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
netlink: 8 bytes leftover after parsing attributes in process
`syz-executor.3'.
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
XFS (loop0): Invalid superblock magic number
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: '7:10' (ffff88820de76ed0): kobject_add_internal: parent: 'bdi',
set: 'devices'
kobject: '7:10' (ffff88820de76ed0): kobject_uevent_env
kobject: '7:10' (ffff88820de76ed0): fill_kobj_path: path
= '/devices/virtual/bdi/7:10'
kobject: 'loop10' (ffff88820de777e0): kobject_add_internal:
parent: 'block', set: 'devices'
kobject: 'loop10' (ffff88820de777e0): kobject_uevent_env
kobject: 'loop10' (ffff88820de777e0): kobject_uevent_env: uevent_suppress
caused the event to drop!
kobject: 'holders' (ffff8880a3d0ce80): kobject_add_internal:
parent: 'loop10', set: '<NULL>'
kobject: 'slaves' (ffff88809680fc80): kobject_add_internal:
parent: 'loop10', set: '<NULL>'
kobject: 'loop10' (ffff88820de777e0): kobject_uevent_env
kobject: 'loop10' (ffff88820de777e0): fill_kobj_path: path
= '/devices/virtual/block/loop10'
kobject: 'queue' (ffff8880a3d308d8): kobject_add_internal:
parent: 'loop10', set: '<NULL>'
kobject: 'mq' (ffff8880a3d30918): kobject_add_internal: parent: 'loop10',
set: '<NULL>'
kobject: 'mq' (ffff8880a3d30918): kobject_uevent_env
kobject: 'mq' (ffff8880a3d30918): kobject_uevent_env: filter function
caused the event to drop!
kobject: '0' (ffff88800e8cf428): kobject_add_internal: parent: 'mq',
set: '<NULL>'
kobject: 'cpu0' (ffffe8ffffc99e98): kobject_add_internal: parent: '0',
set: '<NULL>'
kobject: 'cpu1' (ffffe8ffffd99e98): kobject_add_internal: parent: '0',
set: '<NULL>'
kobject: 'queue' (ffff8880a3d308d8): kobject_uevent_env
kobject: 'queue' (ffff8880a3d308d8): kobject_uevent_env: filter function
caused the event to drop!
kobject: 'iosched' (ffff88800e8ce490): kobject_add_internal:
parent: 'queue', set: '<NULL>'
kobject: 'iosched' (ffff88800e8ce490): kobject_uevent_env
kobject: 'iosched' (ffff88800e8ce490): kobject_uevent_env: filter function
caused the event to drop!
kobject: 'integrity' (ffff88820de77cd0): kobject_add_internal:
parent: 'loop10', set: '<NULL>'
kobject: 'integrity' (ffff88820de77cd0): kobject_uevent_env
kobject: 'integrity' (ffff88820de77cd0): kobject_uevent_env: filter
function caused the event to drop!
print_req_error: I/O error, dev loop10, sector 0
f2fs_msg: 40 callbacks suppressed
F2FS-fs (loop10): Unable to read 1th superblock
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
print_req_error: I/O error, dev loop10, sector 8
F2FS-fs (loop10): Unable to read 2th superblock
print_req_error: I/O error, dev loop10, sector 0
F2FS-fs (loop10): Unable to read 1th superblock
print_req_error: I/O error, dev loop10, sector 8
F2FS-fs (loop10): Unable to read 2th superblock
print_req_error: I/O error, dev loop10, sector 0
F2FS-fs (loop10): Unable to read 1th superblock
print_req_error: I/O error, dev loop10, sector 8
F2FS-fs (loop10): Unable to read 2th superblock
print_req_error: I/O error, dev loop10, sector 0
F2FS-fs (loop10): Unable to read 1th superblock
print_req_error: I/O error, dev loop10, sector 8
F2FS-fs (loop10): Unable to read 2th superblock
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
print_req_error: I/O error, dev loop10, sector 0
F2FS-fs (loop10): Unable to read 1th superblock
print_req_error: I/O error, dev loop10, sector 8
F2FS-fs (loop10): Unable to read 2th superblock
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
device sit0 entered promiscuous mode
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
device sit0 left promiscuous mode
device sit0 entered promiscuous mode
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
device sit0 left promiscuous mode
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
device sit0 entered promiscuous mode
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
device sit0 left promiscuous mode
device sit0 left promiscuous mode
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
device sit0 entered promiscuous mode
device sit0 entered promiscuous mode
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
device sit0 left promiscuous mode
device sit0 entered promiscuous mode
device sit0 left promiscuous mode
device sit0 entered promiscuous mode
netlink: 49 bytes leftover after parsing attributes in process
`syz-executor.5'.
device sit0 entered promiscuous mode
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
netlink: 49 bytes leftover after parsing attributes in process
`syz-executor.5'.
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
netlink: 49 bytes leftover after parsing attributes in process
`syz-executor.5'.
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
device sit0 left promiscuous mode
device sit0 entered promiscuous mode
netlink: 49 bytes leftover after parsing attributes in process
`syz-executor.5'.
device sit0 left promiscuous mode
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
device sit0 entered promiscuous mode
netlink: 49 bytes leftover after parsing attributes in process
`syz-executor.5'.
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'
kobject: 'loop0' (ffff88807680cbe0): kobject_uevent_env
kobject: 'loop0' (ffff88807680cbe0): fill_kobj_path: path
= '/devices/virtual/block/loop0'
device sit0 left promiscuous mode
kobject: 'loop4' (ffff8880a4ab40e0): kobject_uevent_env
kobject: 'loop4' (ffff8880a4ab40e0): fill_kobj_path: path
= '/devices/virtual/block/loop4'


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Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.