arch/x86/mm/kmemcheck/selftest.c

   1 #include <linux/kernel.h>
   2
   3 #include "opcode.h"
   4 #include "selftest.h"
   5
   6 struct selftest_opcode {
   7         unsigned int expected_size;
   8         const uint8_t *insn;
   9         const char *desc;
  10 };
  11
  12 static const struct selftest_opcode selftest_opcodes[] = {
  13         /* REP MOVS */
  14         {1, "\xf3\xa4",                 "rep movsb <mem8>, <mem8>"},
  15         {4, "\xf3\xa5",                 "rep movsl <mem32>, <mem32>"},
  16
  17         /* MOVZX / MOVZXD */
  18         {1, "\x66\x0f\xb6\x51\xf8",     "movzwq <mem8>, <reg16>"},
  19         {1, "\x0f\xb6\x51\xf8",         "movzwq <mem8>, <reg32>"},
  20
  21         /* MOVSX / MOVSXD */
  22         {1, "\x66\x0f\xbe\x51\xf8",     "movswq <mem8>, <reg16>"},
  23         {1, "\x0f\xbe\x51\xf8",         "movswq <mem8>, <reg32>"},
  24
  25 #ifdef CONFIG_X86_64
  26         /* MOVZX / MOVZXD */
  27         {1, "\x49\x0f\xb6\x51\xf8",     "movzbq <mem8>, <reg64>"},
  28         {2, "\x49\x0f\xb7\x51\xf8",     "movzbq <mem16>, <reg64>"},
  29
  30         /* MOVSX / MOVSXD */
  31         {1, "\x49\x0f\xbe\x51\xf8",     "movsbq <mem8>, <reg64>"},
  32         {2, "\x49\x0f\xbf\x51\xf8",     "movsbq <mem16>, <reg64>"},
  33         {4, "\x49\x63\x51\xf8",         "movslq <mem32>, <reg64>"},
  34 #endif
  35 };
  36
  37 static bool selftest_opcode_one(const struct selftest_opcode *op)
  38 {
  39         unsigned size;
  40
  41         kmemcheck_opcode_decode(op->insn, &size);
  42
  43         if (size == op->expected_size)
  44                 return true;
  45
  46         printk(KERN_WARNING "kmemcheck: opcode %s: expected size %d, got %d\n",
  47                 op->desc, op->expected_size, size);
  48         return false;
  49 }
  50
  51 static bool selftest_opcodes_all(void)
  52 {
  53         bool pass = true;
  54         unsigned int i;
  55
  56         for (i = 0; i < ARRAY_SIZE(selftest_opcodes); ++i)
  57                 pass = pass && selftest_opcode_one(&selftest_opcodes[i]);
  58
  59         return pass;
  60 }
  61
  62 bool kmemcheck_selftest(void)
  63 {
  64         bool pass = true;
  65
  66         pass = pass && selftest_opcodes_all();
  67
  68         return pass;
  69 }