kern/143184: [zfs] [lor] zfs/bufwait LOR

[Peter Jeremy]

>Number:         143184
>Category:       kern
>Synopsis:       [zfs] [lor] zfs/bufwait LOR
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Jan 24 20:30:05 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Peter Jeremy
>Release:        FreeBSD 8.0-STABLE amd64
>Organization:
n/a
>Environment:
System: FreeBSD server.vk2pj.dyndns.org 8.0-STABLE FreeBSD 8.0-STABLE #11: Mon Nov 30 16:36:34 EST 2009 root at server.vk2pj.dyndns.org:/var/obj/usr/src/sys/server amd64

>Description:
	New LOR:
lock order reversal:
 1st 0xffffff002f7fb270 zfs (zfs) @ /usr/src/sys/kern/vfs_vnops.c:533
 2nd 0xffffff80803a26e0 bufwait (bufwait) @ /usr/src/sys/vm/vm_pager.c:311
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2a
_witness_debugger() at _witness_debugger+0x2c
witness_checkorder() at witness_checkorder+0x66f
__lockmgr_args() at __lockmgr_args+0x475
initpbuf() at initpbuf+0xb9
getpbuf() at getpbuf+0xdc
swap_pager_getpages() at swap_pager_getpages+0x1aa
vm_fault() at vm_fault+0x5f7
trap_pfault() at trap_pfault+0x128
trap() at trap+0x379
calltrap() at calltrap+0x8
--- trap 0xc, rip = 0xffffffff8049497b, rsp = 0xffffff809a427830, rbp = 0xffffff809a4278b0 ---
copyout() at copyout+0x3b
dmu_read_uio() at dmu_read_uio+0x98
zfs_freebsd_read() at zfs_freebsd_read+0x56f
VOP_READ_APV() at VOP_READ_APV+0x44
vn_read() at vn_read+0x149
dofileread() at dofileread+0xa1
kern_readv() at kern_readv+0x60
read() at read+0x55
syscall() at syscall+0x1ac
Xfast_syscall() at Xfast_syscall+0xe1
--- syscall (3, FreeBSD ELF64, read), rip = 0x8008ce86c, rsp = 0x7ffffffeb718, rbp = 0x805b41d18 ---

>How-To-Repeat:
	Unknown
>Fix:
	Unknown


>Release-Note:
>Audit-Trail:
>Unformatted: