panic: HYPERVISOR_mmu_update failed

[Sarton O'Brien <bsd-xen%roguewrt.org@localhost>]

# gdb -w netbsd.gdb /dev/mem
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xpq_flush_queue: 1 entries
0x000000004324f020: 0x0000000000000225
panic: HYPERVISOR_mmu_update failed

fatal breakpoint trap in supervisor mode
trap type 1 code 0 rip ffffffff803649f5 cs e030 rflags 246 cr2  54dfa0 
cpl 6 rsp ffffa00013afa7e0
Stopped in pid 496.1 (gdb) at   netbsd:breakpoint+0x5:  leave
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x255
xpq_flush_queue() at netbsd:xpq_flush_queue+0xaf
pmap_enter_ma() at netbsd:pmap_enter_ma+0x4ec
pmap_enter() at netbsd:pmap_enter+0x5a
mmrw() at netbsd:mmrw+0x1c2
spec_read() at netbsd:spec_read+0x1f6
VOP_READ() at netbsd:VOP_READ+0x2d
vn_read() at netbsd:vn_read+0x9f
dofileread() at netbsd:dofileread+0x7e
sys_read() at netbsd:sys_read+0x72
syscall() at netbsd:syscall+0x98
ds          0xa7f0
es          0x57cc
fs          0xa7f0
gs          0x58a7
rdi         0
rsi         0xd
rbp         0xffffa00013afa7e0
rbx         0xffffa00013afa7f0
rdx         0
rcx         0
rax         0x1
r8          0xffffffff80578240  cpu_info_primary
r9          0x1
r10         0xffffa00013afa700
r11         0xffffffff8037c420  xenconscn_putc
r12         0x100
r13         0xffffffff803f330b  copyright+0x12eab
r14         0x225
r15         0xffffffff80633600  kernel_pmap_store
rip         0xffffffff803649f5  breakpoint+0x5
cs          0xe030
rflags      0x246
rsp         0xffffa00013afa7e0
ss          0xe02b
netbsd:breakpoint+0x5:  leave
db>