svn commit: r243703 - projects/bhyve/sys/amd64/vmm

[Peter Grehan]

Author: grehan
Date: Fri Nov 30 05:40:24 2012
New Revision: 243703
URL: http://svnweb.freebsd.org/changeset/base/243703

Log:
  Properly screen for the AND 0x81 instruction from the set
  of group1 0x81 instructions that use the reg bits as an
  extended opcode.
  
  Still todo: properly update rflags.
  
  Pointed out by:	jilles@

Modified:
  projects/bhyve/sys/amd64/vmm/vmm_instruction_emul.c

Modified: projects/bhyve/sys/amd64/vmm/vmm_instruction_emul.c
==============================================================================
--- projects/bhyve/sys/amd64/vmm/vmm_instruction_emul.c	Fri Nov 30 05:30:31 2012	(r243702)
+++ projects/bhyve/sys/amd64/vmm/vmm_instruction_emul.c	Fri Nov 30 05:40:24 2012	(r243703)
@@ -83,6 +83,7 @@ static const struct vie_op one_byte_opco
 		.op_type = VIE_OP_TYPE_AND,
 	},
 	[0x81] = {
+		/* XXX Group 1 extended opcode - not just AND */
 		.op_byte = 0x81,
 		.op_type = VIE_OP_TYPE_AND,
 		.op_flags = VIE_OP_F_IMM,
@@ -311,7 +312,13 @@ emulate_and(void *vm, int vcpuid, uint64
 		 *
 		 * 81/          and r/m32, imm32
 		 * REX.W + 81/  and r/m64, imm32 sign-extended to 64
+		 *
+		 * Currently, only the AND operation of the 0x81 opcode
+		 * is implemented (ModRM:reg = b100).
 		 */
+		if ((vie->reg & 7) != 4)
+			break;
+
 		if (vie->rex_w)
 			size = 8;