possible deadlock in bond_get_stats (2)

From: syzbot
Date: Mon Dec 03 2018 - 18:10:14 EST


Hello,

syzbot found the following crash on:

HEAD commit: 93029d7d407f Merge git://git.kernel.org/pub/scm/linux/kern..
git tree: net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=122b11a3400000
kernel config: https://syzkaller.appspot.com/x/.config?x=28ecefa8a6e10719
dashboard link: https://syzkaller.appspot.com/bug?extid=de40a1dd58ea38aa9317
compiler: gcc (GCC) 8.0.1 20180413 (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+de40a1dd58ea38aa9317@xxxxxxxxxxxxxxxxxxxxxxxxx

============================================
WARNING: possible recursive locking detected
4.20.0-rc4+ #321 Not tainted
--------------------------------------------
syz-executor3/31950 is trying to acquire lock:
00000000e8d452b6 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xe1/0x5a0 drivers/net/bonding/bond_main.c:3437

but task is already holding lock:
00000000f1ee61c5 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xe1/0x5a0 drivers/net/bonding/bond_main.c:3437

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
----
lock(&(&bond->stats_lock)->rlock#2/2);
lock(&(&bond->stats_lock)->rlock#2/2);

*** DEADLOCK ***

May be due to missing lock nesting notation

3 locks held by syz-executor3/31950:
#0: 0000000077a61bd6 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
#0: 0000000077a61bd6 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40e/0xc20 net/core/rtnetlink.c:4952
#1: 00000000f1ee61c5 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xe1/0x5a0 drivers/net/bonding/bond_main.c:3437
#2: 00000000dc819414 (rcu_read_lock){....}, at: bond_get_nest_level drivers/net/bonding/bond_main.c:3426 [inline]
#2: 00000000dc819414 (rcu_read_lock){....}, at: bond_get_stats+0xc0/0x5a0 drivers/net/bonding/bond_main.c:3437

stack backtrace:
CPU: 0 PID: 31950 Comm: syz-executor3 Not tainted 4.20.0-rc4+ #321
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x244/0x39d lib/dump_stack.c:113
print_deadlock_bug kernel/locking/lockdep.c:1761 [inline]
check_deadlock kernel/locking/lockdep.c:1805 [inline]
validate_chain kernel/locking/lockdep.c:2331 [inline]
__lock_acquire.cold.61+0x164/0x4e7 kernel/locking/lockdep.c:3341
lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844
_raw_spin_lock_nested+0x33/0x50 kernel/locking/spinlock.c:354
bond_get_stats+0xe1/0x5a0 drivers/net/bonding/bond_main.c:3437
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
dev_get_stats+0x10f/0x470 net/core/dev.c:8865
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
bond_get_stats+0x261/0x5a0 drivers/net/bonding/bond_main.c:3443
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
dev_get_stats+0x10f/0x470 net/core/dev.c:8865
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
rtnl_fill_stats+0x4d/0xac0 net/core/rtnetlink.c:1182
rtnl_fill_ifinfo+0x1c62/0x4670 net/core/rtnetlink.c:1665
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
rtmsg_ifinfo_build_skb+0xc9/0x190 net/core/rtnetlink.c:3400
rtmsg_ifinfo_event.part.31+0x45/0xe0 net/core/rtnetlink.c:3432
rtmsg_ifinfo_event net/core/rtnetlink.c:3429 [inline]
rtnetlink_event+0x144/0x170 net/core/rtnetlink.c:5006
notifier_call_chain+0x17e/0x380 kernel/notifier.c:93
__raw_notifier_call_chain kernel/notifier.c:394 [inline]
raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1733
call_netdevice_notifiers net/core/dev.c:1751 [inline]
netdev_features_change net/core/dev.c:1319 [inline]
netdev_change_features+0xb3/0x110 net/core/dev.c:8308
bond_compute_features.isra.47+0x5b0/0xac0 drivers/net/bonding/bond_main.c:1115
bond_enslave+0x2944/0x6290 drivers/net/bonding/bond_main.c:1760
do_set_master+0x1c9/0x220 net/core/rtnetlink.c:2364
do_setlink+0xbe6/0x3f20 net/core/rtnetlink.c:2498
rtnl_setlink+0x2a2/0x440 net/core/rtnetlink.c:2752
rtnetlink_rcv_msg+0x46a/0xc20 net/core/rtnetlink.c:4955
netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477
rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4973
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0x5a5/0x760 net/netlink/af_netlink.c:1336
netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xd5/0x120 net/socket.c:631
___sys_sendmsg+0x7fd/0x930 net/socket.c:2116
__sys_sendmsg+0x11d/0x280 net/socket.c:2154
__do_sys_sendmsg net/socket.c:2163 [inline]
__se_sys_sendmsg net/socket.c:2161 [inline]
__x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f9b5d549c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000006
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9b5d54a6d4
R13: 00000000004c3fff R14: 00000000004d6838 R15: 00000000ffffffff
bond2: Enslaving bond0 as an active interface with an up link
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): bond2: link becomes ready
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready
device eql left promiscuous mode
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
IPv6: ADDRCONF(NETDEV_UP): veth2: link is not ready
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
IPv6: ADDRCONF(NETDEV_UP): veth3: link is not ready
IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
IPv6: ADDRCONF(NETDEV_UP): wlan1: link is not ready
device tunl0 left promiscuous mode
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
device bond0 left promiscuous mode
IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
8021q: adding VLAN 0 to HW filter on device team0
IPv6: ADDRCONF(NETDEV_UP): : link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): bridge_slave_0: link becomes ready
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered forwarding state
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
IPv6: ADDRCONF(NETDEV_CHANGE): veth3: link becomes ready
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): veth2: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): : link becomes ready
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop5' (00000000c98bcd82): kobject_uevent_env
kobject: 'loop5' (00000000c98bcd82): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop2' (0000000038272514): kobject_uevent_env
kobject: 'loop2' (0000000038272514): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop0' (000000006ea57f40): kobject_uevent_env
kobject: 'loop0' (000000006ea57f40): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env
kobject: 'loop1' (0000000047f5c215): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop3' (00000000e251f307): kobject_uevent_env
kobject: 'loop3' (00000000e251f307): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (000000003c8f155d): kobject_uevent_env
kobject: 'loop4' (000000003c8f155d): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (0000000047f5c215): kobject_uevent_env


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