Commit 72bb8f8c authored by Jason A. Donenfeld's avatar Jason A. Donenfeld Committed by Ingo Molnar
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x86/insn: Avoid namespace clash by separating instruction decoder MMIO type from MMIO trace type 



Both <linux/mmiotrace.h> and <asm/insn-eval.h> define various MMIO_ enum constants,
whose namespace overlaps.

Rename the <asm/insn-eval.h> ones to have a INSN_ prefix, so that the headers can be
used from the same source file.

Signed-off-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230101162910.710293-2-Jason@zx2c4.com
parent 55d23536

arch/x86/coco/tdx/tdx.c

+13 −13
Original line number Diff line number Diff line
@@ -386,8 +386,8 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve) 
{

	unsigned long *reg, val, vaddr;

	char buffer[MAX_INSN_SIZE];

	enum insn_mmio_type mmio;

	struct insn insn = {};

	enum mmio_type mmio;

	int size, extend_size;

	u8 extend_val = 0;
@@ -402,10 +402,10 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve) 
		return -EINVAL;



	mmio = insn_decode_mmio(&insn, &size);

	if (WARN_ON_ONCE(mmio == MMIO_DECODE_FAILED))

	if (WARN_ON_ONCE(mmio == INSN_MMIO_DECODE_FAILED))

		return -EINVAL;



	if (mmio != MMIO_WRITE_IMM && mmio != MMIO_MOVS) {

	if (mmio != INSN_MMIO_WRITE_IMM && mmio != INSN_MMIO_MOVS) {

		reg = insn_get_modrm_reg_ptr(&insn, regs);

		if (!reg)

			return -EINVAL;
@@ -426,23 +426,23 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve) 


	/* Handle writes first */

	switch (mmio) {

	case MMIO_WRITE:

	case INSN_MMIO_WRITE:

		memcpy(&val, reg, size);

		if (!mmio_write(size, ve->gpa, val))

			return -EIO;

		return insn.length;

	case MMIO_WRITE_IMM:

	case INSN_MMIO_WRITE_IMM:

		val = insn.immediate.value;

		if (!mmio_write(size, ve->gpa, val))

			return -EIO;

		return insn.length;

	case MMIO_READ:

	case MMIO_READ_ZERO_EXTEND:

	case MMIO_READ_SIGN_EXTEND:

	case INSN_MMIO_READ:

	case INSN_MMIO_READ_ZERO_EXTEND:

	case INSN_MMIO_READ_SIGN_EXTEND:

		/* Reads are handled below */

		break;

	case MMIO_MOVS:

	case MMIO_DECODE_FAILED:

	case INSN_MMIO_MOVS:

	case INSN_MMIO_DECODE_FAILED:

		/*

		 * MMIO was accessed with an instruction that could not be

		 * decoded or handled properly. It was likely not using io.h
@@ -459,15 +459,15 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve) 
		return -EIO;



	switch (mmio) {

	case MMIO_READ:

	case INSN_MMIO_READ:

		/* Zero-extend for 32-bit operation */

		extend_size = size == 4 ? sizeof(*reg) : 0;

		break;

	case MMIO_READ_ZERO_EXTEND:

	case INSN_MMIO_READ_ZERO_EXTEND:

		/* Zero extend based on operand size */

		extend_size = insn.opnd_bytes;

		break;

	case MMIO_READ_SIGN_EXTEND:

	case INSN_MMIO_READ_SIGN_EXTEND:

		/* Sign extend based on operand size */

		extend_size = insn.opnd_bytes;

		if (size == 1 && val & BIT(7))

arch/x86/include/asm/insn-eval.h

+9 −9
Original line number Diff line number Diff line
@@ -32,16 +32,16 @@ int insn_fetch_from_user_inatomic(struct pt_regs *regs, 
bool insn_decode_from_regs(struct insn *insn, struct pt_regs *regs,

			   unsigned char buf[MAX_INSN_SIZE], int buf_size);



enum mmio_type {

	MMIO_DECODE_FAILED,

	MMIO_WRITE,

	MMIO_WRITE_IMM,

	MMIO_READ,

	MMIO_READ_ZERO_EXTEND,

	MMIO_READ_SIGN_EXTEND,

	MMIO_MOVS,

enum insn_mmio_type {

	INSN_MMIO_DECODE_FAILED,

	INSN_MMIO_WRITE,

	INSN_MMIO_WRITE_IMM,

	INSN_MMIO_READ,

	INSN_MMIO_READ_ZERO_EXTEND,

	INSN_MMIO_READ_SIGN_EXTEND,

	INSN_MMIO_MOVS,

};



enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes);

enum insn_mmio_type insn_decode_mmio(struct insn *insn, int *bytes);



#endif /* _ASM_X86_INSN_EVAL_H */

arch/x86/kernel/sev.c

+9 −9
Original line number Diff line number Diff line
@@ -1536,32 +1536,32 @@ static enum es_result vc_handle_mmio_movs(struct es_em_ctxt *ctxt, 
static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)

{

	struct insn *insn = &ctxt->insn;

	enum insn_mmio_type mmio;

	unsigned int bytes = 0;

	enum mmio_type mmio;

	enum es_result ret;

	u8 sign_byte;

	long *reg_data;



	mmio = insn_decode_mmio(insn, &bytes);

	if (mmio == MMIO_DECODE_FAILED)

	if (mmio == INSN_MMIO_DECODE_FAILED)

		return ES_DECODE_FAILED;



	if (mmio != MMIO_WRITE_IMM && mmio != MMIO_MOVS) {

	if (mmio != INSN_MMIO_WRITE_IMM && mmio != INSN_MMIO_MOVS) {

		reg_data = insn_get_modrm_reg_ptr(insn, ctxt->regs);

		if (!reg_data)

			return ES_DECODE_FAILED;

	}



	switch (mmio) {

	case MMIO_WRITE:

	case INSN_MMIO_WRITE:

		memcpy(ghcb->shared_buffer, reg_data, bytes);

		ret = vc_do_mmio(ghcb, ctxt, bytes, false);

		break;

	case MMIO_WRITE_IMM:

	case INSN_MMIO_WRITE_IMM:

		memcpy(ghcb->shared_buffer, insn->immediate1.bytes, bytes);

		ret = vc_do_mmio(ghcb, ctxt, bytes, false);

		break;

	case MMIO_READ:

	case INSN_MMIO_READ:

		ret = vc_do_mmio(ghcb, ctxt, bytes, true);

		if (ret)

			break;
@@ -1572,7 +1572,7 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) 


		memcpy(reg_data, ghcb->shared_buffer, bytes);

		break;

	case MMIO_READ_ZERO_EXTEND:

	case INSN_MMIO_READ_ZERO_EXTEND:

		ret = vc_do_mmio(ghcb, ctxt, bytes, true);

		if (ret)

			break;
@@ -1581,7 +1581,7 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) 
		memset(reg_data, 0, insn->opnd_bytes);

		memcpy(reg_data, ghcb->shared_buffer, bytes);

		break;

	case MMIO_READ_SIGN_EXTEND:

	case INSN_MMIO_READ_SIGN_EXTEND:

		ret = vc_do_mmio(ghcb, ctxt, bytes, true);

		if (ret)

			break;
@@ -1600,7 +1600,7 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt) 
		memset(reg_data, sign_byte, insn->opnd_bytes);

		memcpy(reg_data, ghcb->shared_buffer, bytes);

		break;

	case MMIO_MOVS:

	case INSN_MMIO_MOVS:

		ret = vc_handle_mmio_movs(ctxt, bytes);

		break;

	default:

arch/x86/lib/insn-eval.c

+10 −10
Original line number Diff line number Diff line
@@ -1595,16 +1595,16 @@ bool insn_decode_from_regs(struct insn *insn, struct pt_regs *regs, 
 * Returns:

 *

 * Type of the instruction. Size of the memory operand is stored in

 * @bytes. If decode failed, MMIO_DECODE_FAILED returned.

 * @bytes. If decode failed, INSN_MMIO_DECODE_FAILED returned.

 */

enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)

enum insn_mmio_type insn_decode_mmio(struct insn *insn, int *bytes)

{

	enum mmio_type type = MMIO_DECODE_FAILED;

	enum insn_mmio_type type = INSN_MMIO_DECODE_FAILED;



	*bytes = 0;



	if (insn_get_opcode(insn))

		return MMIO_DECODE_FAILED;

		return INSN_MMIO_DECODE_FAILED;



	switch (insn->opcode.bytes[0]) {

	case 0x88: /* MOV m8,r8 */
@@ -1613,7 +1613,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes) 
	case 0x89: /* MOV m16/m32/m64, r16/m32/m64 */

		if (!*bytes)

			*bytes = insn->opnd_bytes;

		type = MMIO_WRITE;

		type = INSN_MMIO_WRITE;

		break;



	case 0xc6: /* MOV m8, imm8 */
@@ -1622,7 +1622,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes) 
	case 0xc7: /* MOV m16/m32/m64, imm16/imm32/imm64 */

		if (!*bytes)

			*bytes = insn->opnd_bytes;

		type = MMIO_WRITE_IMM;

		type = INSN_MMIO_WRITE_IMM;

		break;



	case 0x8a: /* MOV r8, m8 */
@@ -1631,7 +1631,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes) 
	case 0x8b: /* MOV r16/r32/r64, m16/m32/m64 */

		if (!*bytes)

			*bytes = insn->opnd_bytes;

		type = MMIO_READ;

		type = INSN_MMIO_READ;

		break;



	case 0xa4: /* MOVS m8, m8 */
@@ -1640,7 +1640,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes) 
	case 0xa5: /* MOVS m16/m32/m64, m16/m32/m64 */

		if (!*bytes)

			*bytes = insn->opnd_bytes;

		type = MMIO_MOVS;

		type = INSN_MMIO_MOVS;

		break;



	case 0x0f: /* Two-byte instruction */
@@ -1651,7 +1651,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes) 
		case 0xb7: /* MOVZX r32/r64, m16 */

			if (!*bytes)

				*bytes = 2;

			type = MMIO_READ_ZERO_EXTEND;

			type = INSN_MMIO_READ_ZERO_EXTEND;

			break;



		case 0xbe: /* MOVSX r16/r32/r64, m8 */
@@ -1660,7 +1660,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes) 
		case 0xbf: /* MOVSX r32/r64, m16 */

			if (!*bytes)

				*bytes = 2;

			type = MMIO_READ_SIGN_EXTEND;

			type = INSN_MMIO_READ_SIGN_EXTEND;

			break;

		}

		break;