diff options
Diffstat (limited to 'arch/x86/kvm/emulate.c')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 53 |
1 files changed, 49 insertions, 4 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 6c5cfe9..8e2a07b 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2961,6 +2961,46 @@ static int em_mov(struct x86_emulate_ctxt *ctxt) return X86EMUL_CONTINUE; } +#define FFL(x) bit(X86_FEATURE_##x) + +static int em_movbe(struct x86_emulate_ctxt *ctxt) +{ + u32 ebx, ecx, edx, eax = 1; + u16 tmp; + + /* + * Check MOVBE is set in the guest-visible CPUID leaf. + */ + ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); + if (!(ecx & FFL(MOVBE))) + return emulate_ud(ctxt); + + switch (ctxt->op_bytes) { + case 2: + /* + * From MOVBE definition: "...When the operand size is 16 bits, + * the upper word of the destination register remains unchanged + * ..." + * + * Both casting ->valptr and ->val to u16 breaks strict aliasing + * rules so we have to do the operation almost per hand. + */ + tmp = (u16)ctxt->src.val; + ctxt->dst.val &= ~0xffffUL; + ctxt->dst.val |= (unsigned long)swab16(tmp); + break; + case 4: + ctxt->dst.val = swab32((u32)ctxt->src.val); + break; + case 8: + ctxt->dst.val = swab64(ctxt->src.val); + break; + default: + return X86EMUL_PROPAGATE_FAULT; + } + return X86EMUL_CONTINUE; +} + static int em_cr_write(struct x86_emulate_ctxt *ctxt) { if (ctxt->ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val)) @@ -3893,11 +3933,11 @@ static const struct opcode twobyte_table[256] = { }; static const struct gprefix three_byte_0f_38_f0 = { - N, N, N, N + I(DstReg | SrcMem | Mov, em_movbe), N, N, N }; static const struct gprefix three_byte_0f_38_f1 = { - N, N, N, N + I(DstMem | SrcReg | Mov, em_movbe), N, N, N }; /* @@ -3907,8 +3947,13 @@ static const struct gprefix three_byte_0f_38_f1 = { static const struct opcode opcode_map_0f_38[256] = { /* 0x00 - 0x7f */ X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), - /* 0x80 - 0xff */ - X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N) + /* 0x80 - 0xef */ + X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), X16(N), + /* 0xf0 - 0xf1 */ + GP(EmulateOnUD | ModRM | Prefix, &three_byte_0f_38_f0), + GP(EmulateOnUD | ModRM | Prefix, &three_byte_0f_38_f1), + /* 0xf2 - 0xff */ + N, N, X4(N), X8(N) }; #undef D |
