diff options
| -rw-r--r-- | arch/x86/kvm/emulate.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index ef23c1e5fa9f..aa272545402e 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2205,12 +2205,15 @@ static int em_cmpxchg(struct x86_emulate_ctxt *ctxt) fastop(ctxt, em_cmp); if (ctxt->eflags & EFLG_ZF) { - /* Success: write back to memory. */ + /* Success: write back to memory; no update of EAX */ + ctxt->src.type = OP_NONE; ctxt->dst.val = ctxt->src.orig_val; } else { /* Failure: write the value we saw to EAX. */ - ctxt->dst.type = OP_REG; - ctxt->dst.addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX); + ctxt->src.type = OP_REG; + ctxt->src.addr.reg = reg_rmw(ctxt, VCPU_REGS_RAX); + ctxt->src.val = ctxt->dst.orig_val; + /* Create write-cycle to dest by writing the same value */ ctxt->dst.val = ctxt->dst.orig_val; } return X86EMUL_CONTINUE; @@ -4157,7 +4160,7 @@ static const struct opcode twobyte_table[256] = { F(DstMem | SrcReg | Src2CL | ModRM, em_shrd), GD(0, &group15), F(DstReg | SrcMem | ModRM, em_imul), /* 0xB0 - 0xB7 */ - I2bv(DstMem | SrcReg | ModRM | Lock | PageTable, em_cmpxchg), + I2bv(DstMem | SrcReg | ModRM | Lock | PageTable | SrcWrite, em_cmpxchg), I(DstReg | SrcMemFAddr | ModRM | Src2SS, em_lseg), F(DstMem | SrcReg | ModRM | BitOp | Lock, em_btr), I(DstReg | SrcMemFAddr | ModRM | Src2FS, em_lseg), |