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Diffstat (limited to 'arch/x86/mm/kmemcheck/opcode.c')
-rw-r--r--arch/x86/mm/kmemcheck/opcode.c106
1 files changed, 0 insertions, 106 deletions
diff --git a/arch/x86/mm/kmemcheck/opcode.c b/arch/x86/mm/kmemcheck/opcode.c
index df8109ddf7fe..cec594032515 100644
--- a/arch/x86/mm/kmemcheck/opcode.c
+++ b/arch/x86/mm/kmemcheck/opcode.c
@@ -1,107 +1 @@
// SPDX-License-Identifier: GPL-2.0
-#include <linux/types.h>
-
-#include "opcode.h"
-
-static bool opcode_is_prefix(uint8_t b)
-{
- return
- /* Group 1 */
- b == 0xf0 || b == 0xf2 || b == 0xf3
- /* Group 2 */
- || b == 0x2e || b == 0x36 || b == 0x3e || b == 0x26
- || b == 0x64 || b == 0x65
- /* Group 3 */
- || b == 0x66
- /* Group 4 */
- || b == 0x67;
-}
-
-#ifdef CONFIG_X86_64
-static bool opcode_is_rex_prefix(uint8_t b)
-{
- return (b & 0xf0) == 0x40;
-}
-#else
-static bool opcode_is_rex_prefix(uint8_t b)
-{
- return false;
-}
-#endif
-
-#define REX_W (1 << 3)
-
-/*
- * This is a VERY crude opcode decoder. We only need to find the size of the
- * load/store that caused our #PF and this should work for all the opcodes
- * that we care about. Moreover, the ones who invented this instruction set
- * should be shot.
- */
-void kmemcheck_opcode_decode(const uint8_t *op, unsigned int *size)
-{
- /* Default operand size */
- int operand_size_override = 4;
-
- /* prefixes */
- for (; opcode_is_prefix(*op); ++op) {
- if (*op == 0x66)
- operand_size_override = 2;
- }
-
- /* REX prefix */
- if (opcode_is_rex_prefix(*op)) {
- uint8_t rex = *op;
-
- ++op;
- if (rex & REX_W) {
- switch (*op) {
- case 0x63:
- *size = 4;
- return;
- case 0x0f:
- ++op;
-
- switch (*op) {
- case 0xb6:
- case 0xbe:
- *size = 1;
- return;
- case 0xb7:
- case 0xbf:
- *size = 2;
- return;
- }
-
- break;
- }
-
- *size = 8;
- return;
- }
- }
-
- /* escape opcode */
- if (*op == 0x0f) {
- ++op;
-
- /*
- * This is move with zero-extend and sign-extend, respectively;
- * we don't have to think about 0xb6/0xbe, because this is
- * already handled in the conditional below.
- */
- if (*op == 0xb7 || *op == 0xbf)
- operand_size_override = 2;
- }
-
- *size = (*op & 1) ? operand_size_override : 1;
-}
-
-const uint8_t *kmemcheck_opcode_get_primary(const uint8_t *op)
-{
- /* skip prefixes */
- while (opcode_is_prefix(*op))
- ++op;
- if (opcode_is_rex_prefix(*op))
- ++op;
- return op;
-}