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/* Test program for PKEYS registers.
Copyright 2015-2020 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <stddef.h>
#include "x86-cpuid.h"
#ifndef NOINLINE
#define NOINLINE __attribute__ ((noinline))
#endif
unsigned int have_pkru (void) NOINLINE;
static inline unsigned long
rdpkru (void)
{
unsigned int eax, edx;
unsigned int ecx = 0;
unsigned int pkru;
asm volatile (".byte 0x0f,0x01,0xee\n\t"
: "=a" (eax), "=d" (edx)
: "c" (ecx));
pkru = eax;
return pkru;
}
static inline void
wrpkru (unsigned int pkru)
{
unsigned int eax = pkru;
unsigned int ecx = 0;
unsigned int edx = 0;
asm volatile (".byte 0x0f,0x01,0xef\n\t"
: : "a" (eax), "c" (ecx), "d" (edx));
}
unsigned int NOINLINE
have_pkru (void)
{
unsigned int eax, ebx, ecx, edx;
if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx))
return 0;
if ((ecx & bit_OSXSAVE) == bit_OSXSAVE)
{
if (__get_cpuid_max (0, NULL) < 7)
return 0;
__cpuid_count (7, 0, eax, ebx, ecx, edx);
if ((ecx & bit_PKU) == bit_PKU)
return 1;
}
return 0;
}
int
main (int argc, char **argv)
{
unsigned int wr_value = 0x12345678;
unsigned int rd_value = 0x0;
if (have_pkru ())
{
wrpkru (wr_value);
asm ("nop\n\t"); /* break here 1. */
rd_value = rdpkru ();
asm ("nop\n\t"); /* break here 2. */
}
return 0;
}
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