KVM: x86 emulator: add support for jmp far 0xea

Add support for jmp far (opcode 0xea) instruction.

Signed-off-by: Guillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: Laurent Vivier <laurent.vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 29 insertions, 2 deletions

diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c
index a928aa6cdad2..48b62cc3bd0c 100644
--- a/arch/x86/kvm/x86_emulate.c
+++ b/arch/x86/kvm/x86_emulate.c
@@ -168,7 +168,8 @@ static u16 opcode_table[256] = {
         /* 0xE0 - 0xE7 */
         0, 0, 0, 0, 0, 0, 0, 0,
         /* 0xE8 - 0xEF */
-        ImplicitOps | Stack, SrcImm|ImplicitOps, 0, SrcImmByte|ImplicitOps,
+        ImplicitOps | Stack, SrcImm | ImplicitOps,
+        ImplicitOps, SrcImmByte | ImplicitOps,
         0, 0, 0, 0,
         /* 0xF0 - 0xF7 */
         0, 0, 0, 0,
@@ -1661,7 +1662,33 @@ special_insn:
                 break;
         }
         case 0xe9: /* jmp rel */
-        case 0xeb: /* jmp rel short */
+                goto jmp;
+        case 0xea: /* jmp far */ {
+                uint32_t eip;
+                uint16_t sel;
+
+                switch (c->op_bytes) {
+                case 2:
+                        eip = insn_fetch(u16, 2, c->eip);
+                        break;
+                case 4:
+                        eip = insn_fetch(u32, 4, c->eip);
+                        break;
+                default:
+                        DPRINTF("jmp far: Invalid op_bytes\n");
+                        goto cannot_emulate;
+                }
+                sel = insn_fetch(u16, 2, c->eip);
+                if (kvm_load_segment_descriptor(ctxt->vcpu, sel, 9, VCPU_SREG_CS) < 0) {
+                        DPRINTF("jmp far: Failed to load CS descriptor\n");
+                        goto cannot_emulate;
+                }
+
+                c->eip = eip;
+                break;
+        }
+        case 0xeb:
+              jmp:              /* jmp rel short */
                 jmp_rel(c, c->src.val);
                 c->dst.type = OP_NONE; /* Disable writeback. */
                 break;