KVM: x86 emulator: drop support for old-style groups (3885d530) · Commits · 戴 / test

arch/x86/kvm/emulate.c

+7 −25

Original line number	Diff line number	Diff line
		@@ -82,7 +82,6 @@
		#define Stack (1<<13) /* Stack instruction (push/pop) */
		#define Group (1<<14) /* Bits 3:5 of modrm byte extend opcode */
		#define GroupDual (1<<15) /* Alternate decoding of mod == 3 */
		#define GroupMask 0x0f /* Group number stored in bits 0:3 */
		/* Misc flags */
		#define Undefined (1<<25) /* No Such Instruction */
		#define Lock (1<<26) /* lock prefix is allowed for the instruction */
		@@ -104,10 +103,6 @@
		#define X8(x) X4(x), X4(x)
		#define X16(x) X8(x), X8(x)

		enum {
		NoGrp,
		};

		struct opcode {
		u32 flags;
		union {
		@@ -174,12 +169,6 @@ static struct group_dual group9 = { {
		N, N, N, N, N, N, N, N,
		} };

		static struct opcode group_table[] = {
		};

		static struct opcode group2_table[] = {
		};

		static struct opcode opcode_table[256] = {
		/* 0x00 - 0x07 */
		D(ByteOp \| DstMem \| SrcReg \| ModRM \| Lock), D(DstMem \| SrcReg \| ModRM \| Lock),
		@@ -959,7 +948,7 @@ x86_decode_insn(struct x86_emulate_ctxt ctxt, struct x86_emulate_ops ops)
		struct decode_cache *c = &ctxt->decode;
		int rc = X86EMUL_CONTINUE;
		int mode = ctxt->mode;
		int def_op_bytes, def_ad_bytes, group, dual, goffset;
		int def_op_bytes, def_ad_bytes, dual, goffset;
		struct opcode opcode, g_mod012, g_mod3;

		/* we cannot decode insn before we complete previous rep insn */
		@@ -1059,24 +1048,17 @@ done_prefixes:
		c->d = opcode.flags;

		if (c->d & Group) {
		group = c->d & GroupMask;
		dual = c->d & GroupDual;
		c->modrm = insn_fetch(u8, 1, c->eip);
		--c->eip;

		if (group) {
		g_mod012 = g_mod3 = &group_table[group * 8];
		if (c->d & GroupDual)
		g_mod3 = &group2_table[group * 8];
		} else {
		if (c->d & GroupDual) {
		g_mod012 = opcode.u.gdual->mod012;
		g_mod3 = opcode.u.gdual->mod3;
		} else
		g_mod012 = g_mod3 = opcode.u.group;
		}

		c->d &= ~(Group \| GroupDual \| GroupMask);
		c->d &= ~(Group \| GroupDual);

		goffset = (c->modrm >> 3) & 7;

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