Page fault in CURRENT

Hi,


The following pagefault just happend on my PV CURRENT domU under Xen 3.3

==================================================================
template_8-CURRENT# pwd
/usr
Kernel page fault with the following non-sleepable locks
held:org/base/head src/
exclusive sleep mutex pmap (pmap) r = 0 (0xc1706ee8) locked
_at_ /usr/src/sys/i386/xen/pmap.c:3711
exclusive sleep mutex vm object (standard object) r = 0 (0xc19c98b8)
locked _at_ /usr/src/sys/vm/vm_pageout.c:771
exclusive sleep mutex vm page queue mutex (vm page queue mutex) r = 0
(0xc052ae84) locked _at_ /usr/src/sys/vm/vm_pageout.c:447
KDB: stack backtrace:
X_db_sym_numargs(c0342b8f,cbe849ac,c010c5f5,c0361da2,1bf,...) at
X_db_sym_numargs+0x146
kdb_backtrace(c0361da2,1bf,ffffffff,c04f2c2c,cbe849e4,...) at
kdb_backtrace+0x29
witness_display_spinlock(c0344dec,cbe849f8,4,1,0,...) at
witness_display_spinlock+0x75
witness_warn(5,0,c036c048,c17a7d80,c,...) at witness_warn+0x1fd
trap(cbe84a80) at trap+0x10e
alltraps(c0bb2d48,4,c0361da2,1a8,c0361da2,...) at alltraps+0x1b
vm_pageout_flush(cbe84ba4,7,0,0,ec1,...) at vm_pageout_flush+0xe5
vm_pageout_flush(c0bb3c78,0,c0361da2,303,32,...) at vm_pageout_flush
+0x621
vm_pageout_flush(0,cbe84d38,c033ba96,32d,c1701a90,...) at
vm_pageout_flush+0x13ce
fork_exit(c02d59b0,0,cbe84d38) at fork_exit+0xb8
fork_trampoline() at fork_trampoline+0x8
--- trap 0, eip = 0, esp = 0xcbe84d70, ebp = 0 ---


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address   = 0xc0863fc8
fault code              = supervisor write, protection violation
instruction pointer     = 0x21:0xc03113df
stack pointer           = 0x29:0xcbe84ac0
frame pointer           = 0x29:0xcbe84ae8
code segment            = base 0x0, limit 0xf67ff, type 0x1b
                        = DPL 1, pres 1, def32 1, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 6 (pagedaemon)
[thread pid 6 tid 100024 ]
Stopped at      pmap_remove_write+0xbf: lock cmpxchgl   %edi,0(%ecx)
db> 
===============================================================

Since I was unable to enter anything at the debugger command line I'm
unable to provide a backtrace. sorry.

--
Olli