KVM: x86 emulator: implement 'push reg' (opcodes 0x50-0x57)

Signed-off-by: Nitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 15 insertions, 1 deletions

diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
index 1036e0224aaa..cf895aab51d6 100644
--- a/drivers/kvm/x86_emulate.c
+++ b/drivers/kvm/x86_emulate.c
@@ -99,7 +99,8 @@ static u8 opcode_table[256] = {
         /* 0x40 - 0x4F */
         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
         /* 0x50 - 0x57 */
-        0, 0, 0, 0, 0, 0, 0, 0,
+        ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
+        ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
         /* 0x58 - 0x5F */
         ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
         ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
@@ -1151,6 +1152,19 @@ special_insn:
         if (twobyte)
                 goto twobyte_special_insn;
         switch(b) {
+        case 0x50 ... 0x57:  /* push reg */
+                if (op_bytes == 2)
+                        src.val = (u16) _regs[b & 0x7];
+                else
+                        src.val = (u32) _regs[b & 0x7];
+                dst.type  = OP_MEM;
+                dst.bytes = op_bytes;
+                dst.val = src.val;
+                register_address_increment(_regs[VCPU_REGS_RSP], -op_bytes);
+                dst.ptr = (void *) register_address(
+                        ctxt->ss_base, _regs[VCPU_REGS_RSP]);
+                no_wb = 1; /* force writeback */
+                break;
         case 0x6c:              /* insb */
         case 0x6d:              /* insw/insd */
                  if (kvm_emulate_pio_string(ctxt->vcpu, NULL,