gdb/testsuite/gdb.arch/i386-pkru.c

   1 /* Test program for PKEYS registers.
   2
   3    Copyright 2015-2023 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include <stddef.h>
  21 #include "x86-cpuid.h"
  22
  23 #ifndef NOINLINE
  24 #define NOINLINE __attribute__ ((noinline))
  25 #endif
  26
  27 unsigned int have_pkru (void) NOINLINE;
  28
  29 static inline unsigned long
  30 rdpkru (void)
  31 {
  32   unsigned int eax, edx;
  33   unsigned int ecx = 0;
  34   unsigned int pkru;
  35
  36   asm volatile (".byte 0x0f,0x01,0xee\n\t"
  37                : "=a" (eax), "=d" (edx)
  38                : "c" (ecx));
  39   pkru = eax;
  40   return pkru;
  41 }
  42
  43 static inline void
  44 wrpkru (unsigned int pkru)
  45 {
  46   unsigned int eax = pkru;
  47   unsigned int ecx = 0;
  48   unsigned int edx = 0;
  49
  50   asm volatile (".byte 0x0f,0x01,0xef\n\t"
  51                : : "a" (eax), "c" (ecx), "d" (edx));
  52 }
  53
  54 unsigned int NOINLINE
  55 have_pkru (void)
  56 {
  57   unsigned int eax, ebx, ecx, edx;
  58
  59   if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx))
  60     return 0;
  61
  62   if ((ecx & bit_OSXSAVE) == bit_OSXSAVE)
  63     {
  64       if (__get_cpuid_max (0, NULL) < 7)
  65         return 0;
  66
  67       __cpuid_count (7, 0, eax, ebx, ecx, edx);
  68
  69       if ((ecx & bit_PKU) == bit_PKU)
  70         return 1;
  71     }
  72   return 0;
  73 }
  74
  75 int
  76 main (int argc, char **argv)
  77 {
  78   unsigned int wr_value = 0x12345678;
  79   unsigned int rd_value = 0x0;
  80
  81   if (have_pkru ())
  82     {
  83       wrpkru (wr_value);
  84       asm ("nop\n\t");  /* break here 1.  */
  85
  86       rd_value = rdpkru ();
  87       asm ("nop\n\t");  /* break here 2.  */
  88     }
  89   return 0;
  90 }