Bug 222053

Summary: [lor] lock order reversal in path
Product: Base System Reporter: Heinz N. Gies <heinz>
Component: kernAssignee: freebsd-bugs (Nobody) <bugs>
Status: New ---    
Severity: Affects Some People    
Priority: ---    
Version: 11.1-STABLE   
Hardware: arm64   
OS: Any   

Description Heinz N. Gies 2017-09-04 16:27:03 UTC 
after `poweroff`:

root@thunderx:~ # poweroff
Shutdown NOW!
poweroff: [pid 581]
root@thunderx:~ #                   Stopping cron.
Waiting for PIDS: 522.
Stopping sshd.
Waiting for PIDS: 512.
Stopping ntpd.
Waiting for PIDS: 482, 482.
Stopping devd.
Waiting for PIDS: 252.
Writing entropy file:.
Writing early boot entropy file:.
.
TerminatedAug 15 06:37:17 thunderx sdone
Waiting (max 60 seconds) for system process `syncer' to stop...
Syncing disks, vnodes remaining... 4 3 0 done
All buffers synced.
lock order reversal:
 1st 0xfffffd000c93d9a0 ufs (ufs) @ /usr/src/sys/kern/path+0x1b4
#2 0xffff00000057bdc4 at VOP_LOCK1_APV+0xcc
#3 0xffff000000364ae0 at _vn_lock+0x6c
#4 0xffff000000356504 at vget+0x78
#5 0xffff000000184bbc at devfs_allocv+0xdc
#6 0xffff0000001846f4 at devfs_root+0x44
#7 0xffff00000034ee1c at dounmount+0x534
#8 0xffff0000003581e8 at vfs_unmountall+0xd4
#9 0xffff000000336df0 at bufshutdown+0x398
#10 0xffff00000029bb6c at kern_reboot+0x1a0
#11 0xffff00000029b960 at sys_reboot+0x378
#12 0xffff00000055eb94 at do_el0_sync+0x864
#13 0xffff0000005481f4 at handle_el0_sync+0x74