diff options
| author | Wei Yongjun <yjwei@cn.fujitsu.com> | 2010-08-04 15:38:18 +0800 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2010-10-24 10:51:00 +0200 |
| commit | 36089fed70337f4d96a5c3aa7fadc4095b707f73 (patch) | |
| tree | 72f8450214eaa8769ec75df3c0dddce8d3bc2f0e /arch/x86/kvm/emulate.c | |
| parent | 06cb704611caf40e531a3835809283f14f5307d5 (diff) | |
KVM: x86 emulator: disable writeback when decode dest operand
This patch change to disable writeback when decode dest
operand if the dest type is ImplicitOps or not specified.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/x86/kvm/emulate.c')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 23 |
1 files changed, 6 insertions, 17 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 6c1e4d6c12cd..e0216eb8b574 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2627,9 +2627,6 @@ done_prefixes: /* Decode and fetch the destination operand: register or memory. */ switch (c->d & DstMask) { - case ImplicitOps: - /* Special instructions do their own operand decoding. */ - return 0; case DstReg: decode_register_operand(&c->dst, c, c->twobyte && (c->b == 0xb6 || c->b == 0xb7)); @@ -2664,6 +2661,11 @@ done_prefixes: c->regs[VCPU_REGS_RDI]); c->dst.val = 0; break; + case ImplicitOps: + /* Special instructions do their own operand decoding. */ + default: + c->dst.type = OP_NONE; /* Disable writeback. */ + return 0; } done: @@ -3115,7 +3117,6 @@ special_insn: case 0xf5: /* cmc */ /* complement carry flag from eflags reg */ ctxt->eflags ^= EFLG_CF; - c->dst.type = OP_NONE; /* Disable writeback. */ break; case 0xf6 ... 0xf7: /* Grp3 */ if (!emulate_grp3(ctxt, ops)) @@ -3123,16 +3124,13 @@ special_insn: break; case 0xf8: /* clc */ ctxt->eflags &= ~EFLG_CF; - c->dst.type = OP_NONE; /* Disable writeback. */ break; case 0xfa: /* cli */ if (emulator_bad_iopl(ctxt, ops)) { emulate_gp(ctxt, 0); goto done; - } else { + } else ctxt->eflags &= ~X86_EFLAGS_IF; - c->dst.type = OP_NONE; /* Disable writeback. */ - } break; case 0xfb: /* sti */ if (emulator_bad_iopl(ctxt, ops)) { @@ -3141,16 +3139,13 @@ special_insn: } else { ctxt->interruptibility = KVM_X86_SHADOW_INT_STI; ctxt->eflags |= X86_EFLAGS_IF; - c->dst.type = OP_NONE; /* Disable writeback. */ } break; case 0xfc: /* cld */ ctxt->eflags &= ~EFLG_DF; - c->dst.type = OP_NONE; /* Disable writeback. */ break; case 0xfd: /* std */ ctxt->eflags |= EFLG_DF; - c->dst.type = OP_NONE; /* Disable writeback. */ break; case 0xfe: /* Grp4 */ grp45: @@ -3287,16 +3282,13 @@ twobyte_insn: break; case 0x06: emulate_clts(ctxt->vcpu); - c->dst.type = OP_NONE; break; case 0x09: /* wbinvd */ kvm_emulate_wbinvd(ctxt->vcpu); - c->dst.type = OP_NONE; break; case 0x08: /* invd */ case 0x0d: /* GrpP (prefetch) */ case 0x18: /* Grp16 (prefetch/nop) */ - c->dst.type = OP_NONE; break; case 0x20: /* mov cr, reg */ switch (c->modrm_reg) { @@ -3349,7 +3341,6 @@ twobyte_insn: goto done; } rc = X86EMUL_CONTINUE; - c->dst.type = OP_NONE; break; case 0x32: /* rdmsr */ @@ -3361,7 +3352,6 @@ twobyte_insn: c->regs[VCPU_REGS_RDX] = msr_data >> 32; } rc = X86EMUL_CONTINUE; - c->dst.type = OP_NONE; break; case 0x34: /* sysenter */ rc = emulate_sysenter(ctxt, ops); @@ -3385,7 +3375,6 @@ twobyte_insn: case 0x80 ... 0x8f: /* jnz rel, etc*/ if (test_cc(c->b, ctxt->eflags)) jmp_rel(c, c->src.val); - c->dst.type = OP_NONE; break; case 0xa0: /* push fs */ emulate_push_sreg(ctxt, ops, VCPU_SREG_FS); |