target/i386: Implement CPUID_EXT_RDRAND

We now have an interface for guest visible random numbers.

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2019-03-14 20:01:42 -07:00
parent 3f74b6322c
commit 369fd5ca66
4 changed files with 73 additions and 17 deletions

View File

@ -730,13 +730,14 @@ static void x86_cpu_vendor_words2str(char *dst, uint32_t vendor1,
CPUID_EXT_MONITOR | CPUID_EXT_SSSE3 | CPUID_EXT_CX16 | \
CPUID_EXT_SSE41 | CPUID_EXT_SSE42 | CPUID_EXT_POPCNT | \
CPUID_EXT_XSAVE | /* CPUID_EXT_OSXSAVE is dynamic */ \
CPUID_EXT_MOVBE | CPUID_EXT_AES | CPUID_EXT_HYPERVISOR)
CPUID_EXT_MOVBE | CPUID_EXT_AES | CPUID_EXT_HYPERVISOR | \
CPUID_EXT_RDRAND)
/* missing:
CPUID_EXT_DTES64, CPUID_EXT_DSCPL, CPUID_EXT_VMX, CPUID_EXT_SMX,
CPUID_EXT_EST, CPUID_EXT_TM2, CPUID_EXT_CID, CPUID_EXT_FMA,
CPUID_EXT_XTPR, CPUID_EXT_PDCM, CPUID_EXT_PCID, CPUID_EXT_DCA,
CPUID_EXT_X2APIC, CPUID_EXT_TSC_DEADLINE_TIMER, CPUID_EXT_AVX,
CPUID_EXT_F16C, CPUID_EXT_RDRAND */
CPUID_EXT_F16C */
#ifdef TARGET_X86_64
#define TCG_EXT2_X86_64_FEATURES (CPUID_EXT2_SYSCALL | CPUID_EXT2_LM)

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@ -226,3 +226,5 @@ DEF_HELPER_3(rcrl, tl, env, tl, tl)
DEF_HELPER_3(rclq, tl, env, tl, tl)
DEF_HELPER_3(rcrq, tl, env, tl, tl)
#endif
DEF_HELPER_1(rdrand, tl, env)

View File

@ -22,6 +22,8 @@
#include "exec/exec-all.h"
#include "qemu/host-utils.h"
#include "exec/helper-proto.h"
#include "qapi/error.h"
#include "qemu/guest-random.h"
//#define DEBUG_MULDIV
@ -470,3 +472,22 @@ void helper_cr4_testbit(CPUX86State *env, uint32_t bit)
raise_exception_ra(env, EXCP06_ILLOP, GETPC());
}
}
target_ulong HELPER(rdrand)(CPUX86State *env)
{
Error *err = NULL;
target_ulong ret;
if (qemu_guest_getrandom(&ret, sizeof(ret), &err) < 0) {
qemu_log_mask(LOG_UNIMP, "rdrand: Crypto failure: %s",
error_get_pretty(err));
error_free(err);
/* Failure clears CF and all other flags, and returns 0. */
env->cc_src = 0;
return 0;
}
/* Success sets CF and clears all others. */
env->cc_src = CC_C;
return ret;
}

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@ -5332,31 +5332,63 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
case 0x1c7: /* cmpxchg8b */
modrm = x86_ldub_code(env, s);
mod = (modrm >> 6) & 3;
if ((mod == 3) || ((modrm & 0x38) != 0x8))
goto illegal_op;
#ifdef TARGET_X86_64
if (dflag == MO_64) {
if (!(s->cpuid_ext_features & CPUID_EXT_CX16))
switch ((modrm >> 3) & 7) {
case 1: /* CMPXCHG8, CMPXCHG16 */
if (mod == 3) {
goto illegal_op;
gen_lea_modrm(env, s, modrm);
if ((s->prefix & PREFIX_LOCK) && (tb_cflags(s->base.tb) & CF_PARALLEL)) {
gen_helper_cmpxchg16b(cpu_env, s->A0);
} else {
gen_helper_cmpxchg16b_unlocked(cpu_env, s->A0);
}
} else
#ifdef TARGET_X86_64
if (dflag == MO_64) {
if (!(s->cpuid_ext_features & CPUID_EXT_CX16)) {
goto illegal_op;
}
gen_lea_modrm(env, s, modrm);
if ((s->prefix & PREFIX_LOCK) &&
(tb_cflags(s->base.tb) & CF_PARALLEL)) {
gen_helper_cmpxchg16b(cpu_env, s->A0);
} else {
gen_helper_cmpxchg16b_unlocked(cpu_env, s->A0);
}
set_cc_op(s, CC_OP_EFLAGS);
break;
}
#endif
{
if (!(s->cpuid_features & CPUID_CX8))
if (!(s->cpuid_features & CPUID_CX8)) {
goto illegal_op;
}
gen_lea_modrm(env, s, modrm);
if ((s->prefix & PREFIX_LOCK) && (tb_cflags(s->base.tb) & CF_PARALLEL)) {
if ((s->prefix & PREFIX_LOCK) &&
(tb_cflags(s->base.tb) & CF_PARALLEL)) {
gen_helper_cmpxchg8b(cpu_env, s->A0);
} else {
gen_helper_cmpxchg8b_unlocked(cpu_env, s->A0);
}
set_cc_op(s, CC_OP_EFLAGS);
break;
case 7: /* RDSEED */
case 6: /* RDRAND */
if (mod != 3 ||
(s->prefix & (PREFIX_LOCK | PREFIX_REPZ | PREFIX_REPNZ)) ||
!(s->cpuid_ext_features & CPUID_EXT_RDRAND)) {
goto illegal_op;
}
if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
gen_io_start();
}
gen_helper_rdrand(s->T0, cpu_env);
rm = (modrm & 7) | REX_B(s);
gen_op_mov_reg_v(s, dflag, rm, s->T0);
set_cc_op(s, CC_OP_EFLAGS);
if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
gen_io_end();
gen_jmp(s, s->pc - s->cs_base);
}
break;
default:
goto illegal_op;
}
set_cc_op(s, CC_OP_EFLAGS);
break;
/**************************/