possible deadlock in genl_rcv (2)

From: syzbot
Date: Fri Jan 11 2019 - 04:43:12 EST


Hello,

syzbot found the following crash on:

HEAD commit: 1bdbe2274920 Merge tag 'vfio-v5.0-rc2' of git://github.com..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=113a7310c00000
kernel config: https://syzkaller.appspot.com/x/.config?x=edf1c3031097c304
dashboard link: https://syzkaller.appspot.com/bug?extid=cf29f8ae16ca7ceb483d
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+cf29f8ae16ca7ceb483d@xxxxxxxxxxxxxxxxxxxxxxxxx

======================================================
WARNING: possible circular locking dependency detected
5.0.0-rc1+ #19 Not tainted
------------------------------------------------------
syz-executor4/9818 is trying to acquire lock:
000000005c79b7a6 (cb_lock){++++}, at: genl_rcv+0x1a/0x40 net/netlink/genetlink.c:636

but task is already holding lock:
00000000074e359b (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline]
00000000074e359b (&pipe->mutex/1){+.+.}, at: pipe_lock+0x6e/0x80 fs/pipe.c:70

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&pipe->mutex/1){+.+.}:
__mutex_lock_common kernel/locking/mutex.c:925 [inline]
__mutex_lock+0x12f/0x1670 kernel/locking/mutex.c:1072
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
pipe_lock_nested fs/pipe.c:62 [inline]
pipe_lock+0x6e/0x80 fs/pipe.c:70
iter_file_splice_write+0x284/0xfc0 fs/splice.c:700
do_splice_from fs/splice.c:851 [inline]
do_splice+0x64b/0x1410 fs/splice.c:1152
__do_sys_splice fs/splice.c:1419 [inline]
__se_sys_splice fs/splice.c:1399 [inline]
__x64_sys_splice+0x2c6/0x330 fs/splice.c:1399
do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #3 (sb_writers#4){.+.+}:
percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline]
percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
__sb_start_write+0x20b/0x360 fs/super.c:1389
sb_start_write include/linux/fs.h:1602 [inline]
mnt_want_write+0x3f/0xc0 fs/namespace.c:357
ovl_want_write+0x76/0xa0 fs/overlayfs/util.c:24
ovl_create_object+0x146/0x3b0 fs/overlayfs/dir.c:599
ovl_create+0x28/0x30 fs/overlayfs/dir.c:630
lookup_open+0x1332/0x1b80 fs/namei.c:3234
do_last fs/namei.c:3324 [inline]
path_openat+0x1983/0x5650 fs/namei.c:3534
PM: Basic memory bitmaps created
do_filp_open+0x26f/0x370 fs/namei.c:3564
do_sys_open+0x59a/0x7c0 fs/open.c:1063
__do_sys_openat fs/open.c:1090 [inline]
__se_sys_openat fs/open.c:1084 [inline]
__x64_sys_openat+0x9d/0x100 fs/open.c:1084
do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
PM: Basic memory bitmaps freed

-> #2 (&ovl_i_mutex_dir_key[depth]){++++}:
down_read+0x8d/0x120 kernel/locking/rwsem.c:24
inode_lock_shared include/linux/fs.h:767 [inline]
lookup_slow+0x4a/0x80 fs/namei.c:1687
walk_component+0x8e5/0x26a0 fs/namei.c:1810
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
link_path_walk.part.0+0xa57/0x1550 fs/namei.c:2141
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
link_path_walk fs/namei.c:2072 [inline]
path_openat+0x222/0x5650 fs/namei.c:3533
do_filp_open+0x26f/0x370 fs/namei.c:3564
file_open_name+0x39e/0x590 fs/open.c:1010
filp_open+0x4c/0x80 fs/open.c:1030
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kernel_read_file_from_path+0x84/0x100 fs/exec.c:974
fw_get_filesystem_firmware drivers/base/firmware_loader/main.c:328 [inline]
_request_firmware+0xa73/0x15c0 drivers/base/firmware_loader/main.c:587
request_firmware+0x38/0x50 drivers/base/firmware_loader/main.c:636
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
reg_reload_regdb+0x84/0x2e0 net/wireless/reg.c:1073
nl80211_reload_regdb+0xe/0x10 net/wireless/nl80211.c:6188
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
genl_family_rcv_msg+0x80d/0x11a0 net/netlink/genetlink.c:601
genl_rcv_msg+0xca/0x16c net/netlink/genetlink.c:626
netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477
genl_rcv+0x29/0x40 net/netlink/genetlink.c:637
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336
netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xdd/0x130 net/socket.c:631
___sys_sendmsg+0x7ec/0x910 net/socket.c:2116
__sys_sendmsg+0x112/0x270 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+0x1a3/0x800 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #1 (genl_mutex){+.+.}:
__mutex_lock_common kernel/locking/mutex.c:925 [inline]
__mutex_lock+0x12f/0x1670 kernel/locking/mutex.c:1072
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
genl_lock net/netlink/genetlink.c:33 [inline]
genl_lock_all net/netlink/genetlink.c:54 [inline]
genl_register_family net/netlink/genetlink.c:331 [inline]
genl_register_family+0x273/0x1450 net/netlink/genetlink.c:322
genl_init+0x17/0x6e net/netlink/genetlink.c:1046
do_one_initcall+0x129/0x937 init/main.c:888
do_initcall_level init/main.c:956 [inline]
do_initcalls init/main.c:964 [inline]
do_basic_setup init/main.c:982 [inline]
kernel_init_freeable+0x4db/0x5ca init/main.c:1135
kernel_init+0x12/0x1c5 init/main.c:1055
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

-> #0 (cb_lock){++++}:
lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841
down_read+0x8d/0x120 kernel/locking/rwsem.c:24
genl_rcv+0x1a/0x40 net/netlink/genetlink.c:636
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336
netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xdd/0x130 net/socket.c:631
kernel_sendmsg+0x44/0x50 net/socket.c:639
sock_no_sendpage+0x1cd/0x260 net/core/sock.c:2587
kernel_sendpage+0x95/0xf0 net/socket.c:3360
sock_sendpage+0x8b/0xc0 net/socket.c:846
pipe_to_sendpage+0x2b4/0x390 fs/splice.c:452
splice_from_pipe_feed fs/splice.c:503 [inline]
__splice_from_pipe+0x39a/0x7e0 fs/splice.c:627
splice_from_pipe+0x1ea/0x310 fs/splice.c:662
generic_splice_sendpage+0x3c/0x50 fs/splice.c:832
do_splice_from fs/splice.c:851 [inline]
do_splice+0x64b/0x1410 fs/splice.c:1152
__do_sys_splice fs/splice.c:1419 [inline]
__se_sys_splice fs/splice.c:1399 [inline]
__x64_sys_splice+0x2c6/0x330 fs/splice.c:1399
do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
cb_lock --> sb_writers#4 --> &pipe->mutex/1

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&pipe->mutex/1);
lock(sb_writers#4);
lock(&pipe->mutex/1);
lock(cb_lock);

*** DEADLOCK ***

1 lock held by syz-executor4/9818:
#0: 00000000074e359b (&pipe->mutex/1){+.+.}, at: pipe_lock_nested fs/pipe.c:62 [inline]
#0: 00000000074e359b (&pipe->mutex/1){+.+.}, at: pipe_lock+0x6e/0x80 fs/pipe.c:70

stack backtrace:
CPU: 1 PID: 9818 Comm: syz-executor4 Not tainted 5.0.0-rc1+ #19
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+0x1db/0x2d0 lib/dump_stack.c:113
print_circular_bug.isra.0.cold+0x1cc/0x28f kernel/locking/lockdep.c:1224
check_prev_add kernel/locking/lockdep.c:1866 [inline]
check_prevs_add kernel/locking/lockdep.c:1979 [inline]
validate_chain kernel/locking/lockdep.c:2350 [inline]
__lock_acquire+0x3014/0x4a30 kernel/locking/lockdep.c:3338
lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841
down_read+0x8d/0x120 kernel/locking/rwsem.c:24
genl_rcv+0x1a/0x40 net/netlink/genetlink.c:636
netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336
netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xdd/0x130 net/socket.c:631
kernel_sendmsg+0x44/0x50 net/socket.c:639
sock_no_sendpage+0x1cd/0x260 net/core/sock.c:2587
kernel_sendpage+0x95/0xf0 net/socket.c:3360
sock_sendpage+0x8b/0xc0 net/socket.c:846
pipe_to_sendpage+0x2b4/0x390 fs/splice.c:452
splice_from_pipe_feed fs/splice.c:503 [inline]
__splice_from_pipe+0x39a/0x7e0 fs/splice.c:627
splice_from_pipe+0x1ea/0x310 fs/splice.c:662
generic_splice_sendpage+0x3c/0x50 fs/splice.c:832
do_splice_from fs/splice.c:851 [inline]
do_splice+0x64b/0x1410 fs/splice.c:1152
__do_sys_splice fs/splice.c:1419 [inline]
__se_sys_splice fs/splice.c:1399 [inline]
__x64_sys_splice+0x2c6/0x330 fs/splice.c:1399
do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457ec9
Code: 6d b7 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007efe4b3c4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457ec9
RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 000000000073bfa0 R08: 0000000000010005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007efe4b3c56d4
R13: 00000000004c6b03 R14: 00000000004db2a8 R15: 00000000ffffffff
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_1
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
PM: Marking nosave pages: [mem 0x00000000-0x00000fff]
PM: Marking nosave pages: [mem 0x0009f000-0x000fffff]
PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff]
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
PM: Basic memory bitmaps created
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
PM: Basic memory bitmaps freed
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
PM: Marking nosave pages: [mem 0x00000000-0x00000fff]
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
PM: Marking nosave pages: [mem 0x0009f000-0x000fffff]
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff]
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
PM: Basic memory bitmaps created
PM: Basic memory bitmaps freed
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
PM: Marking nosave pages: [mem 0x00000000-0x00000fff]
PM: Marking nosave pages: [mem 0x0009f000-0x000fffff]
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff]
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
PM: Basic memory bitmaps created
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
PM: Basic memory bitmaps freed
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
PM: Marking nosave pages: [mem 0x00000000-0x00000fff]
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
PM: Marking nosave pages: [mem 0x0009f000-0x000fffff]
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff]
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
net_ratelimit: 14 callbacks suppressed
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
protocol 88fb is buggy, dev hsr_slave_1
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
PM: Basic memory bitmaps created
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
PM: Basic memory bitmaps freed
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
PM: Marking nosave pages: [mem 0x00000000-0x00000fff]
PM: Marking nosave pages: [mem 0x0009f000-0x000fffff]
PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff]
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
PM: Basic memory bitmaps created
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
PM: Basic memory bitmaps freed
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
PM: Marking nosave pages: [mem 0x00000000-0x00000fff]
PM: Marking nosave pages: [mem 0x0009f000-0x000fffff]
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff]
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'nullb0' (00000000cfa0c564): kobject_uevent_env
kobject: 'nullb0' (00000000cfa0c564): fill_kobj_path: path = '/devices/virtual/block/nullb0'
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_0
PM: Basic memory bitmaps created
PM: Basic memory bitmaps freed
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'
kobject: 'loop4' (000000001bbb4ef4): kobject_uevent_env
kobject: 'loop4' (000000001bbb4ef4): fill_kobj_path: path = '/devices/virtual/block/loop4'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop2' (00000000e2fb39bc): kobject_uevent_env
kobject: 'loop2' (00000000e2fb39bc): fill_kobj_path: path = '/devices/virtual/block/loop2'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (00000000a9fd9365): kobject_uevent_env
kobject: 'loop1' (00000000a9fd9365): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop3' (00000000e85e5389): kobject_uevent_env
kobject: 'loop3' (00000000e85e5389): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop5' (000000009b3748cc): kobject_uevent_env
kobject: 'loop5' (000000009b3748cc): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'loop0' (00000000016ca69e): kobject_uevent_env
kobject: 'loop0' (00000000016ca69e): fill_kobj_path: path = '/devices/virtual/block/loop0'


---
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