8.0-RC1: kernel page fault in NLM master thread (VIMAGE or ZFS related?)

All,

I just got this overnight on my server:

Fatal trap 12: page fault while in kernel mode
fault virtual address	= 0x90
fault code		= supervisor read, page not present
instruction pointer	= 0x20:0xc05ba39d
stack pointer	        = 0x28:0xf31077bc
frame pointer	        = 0x28:0xf31077c8
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, def32 1, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 928 (NLM: master)

(kgdb) bt
#0  doadump () at pcpu.h:246
#1  0xc05e03f3 in boot (howto=260) at /zmirror/nfs/freebsd/base/stable/ 
8/sys/kern/kern_shutdown.c:416
#2  0xc05e062d in panic (fmt=Variable "fmt" is not available.
) at /zmirror/nfs/freebsd/base/stable/8/sys/kern/kern_shutdown.c:579
#3  0xc04ac807 in db_panic (addr=Could not find the frame base for  
"db_panic".
) at /zmirror/nfs/freebsd/base/stable/8/sys/ddb/db_command.c:478
#4  0xc04acd91 in db_command (last_cmdp=0xc0881c3c, cmd_table=0x0,  
dopager=1) at /zmirror/nfs/freebsd/base/stable/8/sys/ddb/db_command.c: 
445
#5  0xc04aceea in db_command_loop () at /zmirror/nfs/freebsd/base/ 
stable/8/sys/ddb/db_command.c:498
#6  0xc04aed5d in db_trap (type=12, code=0) at /zmirror/nfs/freebsd/ 
base/stable/8/sys/ddb/db_main.c:229
#7  0xc0608a14 in kdb_trap (type=12, code=0, tf=0xf310777c) at / 
zmirror/nfs/freebsd/base/stable/8/sys/kern/subr_kdb.c:535
#8  0xc07c53af in trap_fatal (frame=0xf310777c, eva=144) at /zmirror/ 
nfs/freebsd/base/stable/8/sys/i386/i386/trap.c:924
#9  0xc07c5650 in trap_pfault (frame=0xf310777c, usermode=0, eva=144)  
at /zmirror/nfs/freebsd/base/stable/8/sys/i386/i386/trap.c:846
#10 0xc07c5ff2 in trap (frame=0xf310777c) at /zmirror/nfs/freebsd/base/ 
stable/8/sys/i386/i386/trap.c:528
#11 0xc07ac50b in calltrap () at /zmirror/nfs/freebsd/base/stable/8/ 
sys/i386/i386/exception.s:165
#12 0xc05ba39d in prison_priv_check (cred=0xc61e4880, priv=334) at / 
zmirror/nfs/freebsd/base/stable/8/sys/kern/kern_jail.c:3568
#13 0xc05d39ee in priv_check_cred (cred=0xc61e4880, priv=334, flags=0)  
at /zmirror/nfs/freebsd/base/stable/8/sys/kern/kern_priv.c:92
#14 0xc09dbffc in secpolicy_fs_owner (mp=0xc4112284, cred=0xc61e4880)  
at /zmirror/nfs/freebsd/base/stable/8/sys/modules/zfs/../../cddl/ 
compat/opensolaris/kern/opensolaris_policy.c:86
#15 0xc09dc527 in secpolicy_vnode_access (cred=0xc61e4880,  
vp=0xc4bb6d9c, owner=501, accmode=128)
     at /zmirror/nfs/freebsd/base/stable/8/sys/modules/zfs/../../cddl/ 
compat/opensolaris/kern/opensolaris_policy.c:125
#16 0xc0a56c5c in zfs_zaccess (zp=0xd4be8658, mode=2, flags=Variable  
"flags" is not available.
) at /zmirror/nfs/freebsd/base/stable/8/sys/modules/zfs/../../cddl/ 
contrib/opensolaris/uts/common/fs/zfs/zfs_acl.c:2445
#17 0xc0a56edb in zfs_zaccess_rwx (zp=0xd4be8658, mode=Variable "mode"  
is not available.
) at /zmirror/nfs/freebsd/base/stable/8/sys/modules/zfs/../../cddl/ 
contrib/opensolaris/uts/common/fs/zfs/zfs_acl.c:2484
#18 0xc0a6bfa4 in zfs_freebsd_access (ap=0xf31078d4) at /zmirror/nfs/ 
freebsd/base/stable/8/sys/modules/zfs/../../cddl/contrib/opensolaris/ 
uts/common/fs/zfs/zfs_vnops.c:1068
#19 0xc07cfeb2 in VOP_ACCESS_APV (vop=0xc0acfac0, a=0xf31078d4) at  
vnode_if.c:571
#20 0xc0718c93 in nlm_get_vfs_state (host=Variable "host" is not  
available.
) at vnode_if.h:254
#21 0xc0718e30 in nlm_do_unlock (argp=0xf31079c8, result=0xf3107a08,  
rqstp=0xcb199800, rpcp=0x0) at /zmirror/nfs/freebsd/base/stable/8/sys/ 
nlm/nlm_prot_impl.c:2227
#22 0xc071ac87 in nlm4_unlock_4_svc (argp=0xf31079c8,  
result=0xf3107a08, rqstp=0xcb199800) at /zmirror/nfs/freebsd/base/ 
stable/8/sys/nlm/nlm_prot_server.c:540
#23 0xc071bce3 in nlm_prog_4 (rqstp=0xcb199800, transp=0xc652de00) at / 
zmirror/nfs/freebsd/base/stable/8/sys/nlm/nlm_prot_svc.c:512
#24 0xc07284bf in svc_run_internal (pool=0xc61e4c80, ismaster=1) at / 
zmirror/nfs/freebsd/base/stable/8/sys/rpc/svc.c:893
#25 0xc072943d in svc_run (pool=0xc61e4c80) at /zmirror/nfs/freebsd/ 
base/stable/8/sys/rpc/svc.c:1233
#26 0xc071a348 in nlm_syscall (td=0xc6551000, uap=0xf3107cf8) at / 
zmirror/nfs/freebsd/base/stable/8/sys/nlm/nlm_prot_impl.c:1593
#27 0xc07c5977 in syscall (frame=0xf3107d38) at /zmirror/nfs/freebsd/ 
base/stable/8/sys/i386/i386/trap.c:1073
#28 0xc07ac570 in Xint0x80_syscall () at /zmirror/nfs/freebsd/base/ 
stable/8/sys/i386/i386/exception.s:261
#29 0x00000033 in ?? ()

(kgdb) frame 12
#12 0xc05ba39d in prison_priv_check (cred=0xc61e4880, priv=334) at / 
zmirror/nfs/freebsd/base/stable/8/sys/kern/kern_jail.c:3568
3568		switch (priv) {
(kgdb) l 3567
3562		 */
3563			if (cred->cr_prison->pr_flags & PR_VNET)
3564				return (0);
3565		}
3566	#endif /* VIMAGE */
3567	
3568		switch (priv) {
3569	
3570			/*
3571			 * Allow ktrace privileges for root in jail.
(kgdb) p cred->cr_prison
$4 = (struct prison *) 0x0

-- 
Marcel Moolenaar
xcllnt_at_mac.com