missing instruction in x86_emul

missing instruction in x86_emul

[Kip Macy]

The nearest I can tell from the output below is that FreeBSD was
killed in _mtx_lock_spin_flags (c0065437) because the instruction
emulator doesn't recognize 0x57 (push  %edi):

00000110 <_mtx_lock_spin_flags>:
 110:   55                      push   %ebp
 111:   89 e5                 mov    %esp,%ebp
 113:   57                      push   %edi

and presumably this was an issue because %edi was the first operation
on a writable pagetable mapped page.

Is this correct?



WP PT_SET ../../../i386-xen/i386-xen/pmap.c:387
(XEN) (file=x86_emulate.c, line=1033) Cannot emulate 57
(XEN) (file=x86_emulate.c, line=1033) Cannot emulate 57
(XEN) (file=traps.c, line=343) Page fault: fc54dda3 -> fc50614e
(XEN) Stack trace from ESP=fc503f44:
(XEN)    fc503f44 fc56e545 00000157 [fc54dda3] [fc50614e] feb9d648
fcfeb34c fc503f44
(XEN)    fcfeb3e4 fcfea740 fcfeb040 [fc50614e] c028cff4 00000003
c028d000 [fc54df1e]
(XEN)    fc503f88 fcfeb040 00010219 fcfeb34c c028cff4 0000000a c028d000 c0065437
(XEN)    000e0003 [fc54dda3] 00000808 00010292 [fc54de75] 00000001
00000001 00000000
(XEN)    c01ef4e0 0000000a c028d000 c02cf000 000e0003 c0065437 00000819 00010246
(XEN)    c028d000 00000821 00000821 00000821 00000019 00000821 fcfeb040
(XEN) Call Trace from ESP=fc503f44:
(XEN)    [<fc54dda3>] [<fc50614e>] [<fc50614e>] [<fc54df1e>]
[<fc54dda3>] [<fc54de75>]
(XEN) Guest EIP is c0065437