cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
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compat.c (9280B)

      1/*
      2 *  PowerPC CPU initialization for qemu.
      3 *
      4 *  Copyright 2016, David Gibson, Red Hat Inc. <dgibson@redhat.com>
      5 *
      6 * This library is free software; you can redistribute it and/or
      7 * modify it under the terms of the GNU Lesser General Public
      8 * License as published by the Free Software Foundation; either
      9 * version 2.1 of the License, or (at your option) any later version.
     10 *
     11 * This library is distributed in the hope that it will be useful,
     12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14 * Lesser General Public License for more details.
     15 *
     16 * You should have received a copy of the GNU Lesser General Public
     17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
     18 */
     19
     20#include "qemu/osdep.h"
     21#include "sysemu/hw_accel.h"
     22#include "sysemu/kvm.h"
     23#include "kvm_ppc.h"
     24#include "sysemu/cpus.h"
     25#include "qemu/error-report.h"
     26#include "qapi/error.h"
     27#include "qapi/visitor.h"
     28#include "cpu-models.h"
     29
     30typedef struct {
     31    const char *name;
     32    uint32_t pvr;
     33    uint64_t pcr;
     34    uint64_t pcr_level;
     35
     36    /*
     37     * Maximum allowed virtual threads per virtual core
     38     *
     39     * This is to stop older guests getting confused by seeing more
     40     * threads than they think the cpu can support.  Usually it's
     41     * equal to the number of threads supported on bare metal
     42     * hardware, but not always (see POWER9).
     43     */
     44    int max_vthreads;
     45} CompatInfo;
     46
     47static const CompatInfo compat_table[] = {
     48    /*
     49     * Ordered from oldest to newest - the code relies on this
     50     */
     51    { /* POWER6, ISA2.05 */
     52        .name = "power6",
     53        .pvr = CPU_POWERPC_LOGICAL_2_05,
     54        .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07 |
     55               PCR_COMPAT_2_06 | PCR_COMPAT_2_05 | PCR_TM_DIS | PCR_VSX_DIS,
     56        .pcr_level = PCR_COMPAT_2_05,
     57        .max_vthreads = 2,
     58    },
     59    { /* POWER7, ISA2.06 */
     60        .name = "power7",
     61        .pvr = CPU_POWERPC_LOGICAL_2_06,
     62        .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07 |
     63               PCR_COMPAT_2_06 | PCR_TM_DIS,
     64        .pcr_level = PCR_COMPAT_2_06,
     65        .max_vthreads = 4,
     66    },
     67    {
     68        .name = "power7+",
     69        .pvr = CPU_POWERPC_LOGICAL_2_06_PLUS,
     70        .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07 |
     71               PCR_COMPAT_2_06 | PCR_TM_DIS,
     72        .pcr_level = PCR_COMPAT_2_06,
     73        .max_vthreads = 4,
     74    },
     75    { /* POWER8, ISA2.07 */
     76        .name = "power8",
     77        .pvr = CPU_POWERPC_LOGICAL_2_07,
     78        .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07,
     79        .pcr_level = PCR_COMPAT_2_07,
     80        .max_vthreads = 8,
     81    },
     82    { /* POWER9, ISA3.00 */
     83        .name = "power9",
     84        .pvr = CPU_POWERPC_LOGICAL_3_00,
     85        .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00,
     86        .pcr_level = PCR_COMPAT_3_00,
     87        /*
     88         * POWER9 hardware only supports 4 threads / core, but this
     89         * limit is for guests.  We need to support 8 vthreads/vcore
     90         * on POWER9 for POWER8 compatibility guests, and it's very
     91         * confusing if half of the threads disappear from the guest
     92         * if it announces it's POWER9 aware at CAS time.
     93         */
     94        .max_vthreads = 8,
     95    },
     96    { /* POWER10, ISA3.10 */
     97        .name = "power10",
     98        .pvr = CPU_POWERPC_LOGICAL_3_10,
     99        .pcr = PCR_COMPAT_3_10,
    100        .pcr_level = PCR_COMPAT_3_10,
    101        .max_vthreads = 8,
    102    },
    103};
    104
    105static const CompatInfo *compat_by_pvr(uint32_t pvr)
    106{
    107    int i;
    108
    109    for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
    110        if (compat_table[i].pvr == pvr) {
    111            return &compat_table[i];
    112        }
    113    }
    114    return NULL;
    115}
    116
    117static bool pcc_compat(PowerPCCPUClass *pcc, uint32_t compat_pvr,
    118                       uint32_t min_compat_pvr, uint32_t max_compat_pvr)
    119{
    120    const CompatInfo *compat = compat_by_pvr(compat_pvr);
    121    const CompatInfo *min = compat_by_pvr(min_compat_pvr);
    122    const CompatInfo *max = compat_by_pvr(max_compat_pvr);
    123
    124    g_assert(!min_compat_pvr || min);
    125    g_assert(!max_compat_pvr || max);
    126
    127    if (!compat) {
    128        /* Not a recognized logical PVR */
    129        return false;
    130    }
    131    if ((min && (compat < min)) || (max && (compat > max))) {
    132        /* Outside specified range */
    133        return false;
    134    }
    135    if (!(pcc->pcr_supported & compat->pcr_level)) {
    136        /* Not supported by this CPU */
    137        return false;
    138    }
    139    return true;
    140}
    141
    142bool ppc_check_compat(PowerPCCPU *cpu, uint32_t compat_pvr,
    143                      uint32_t min_compat_pvr, uint32_t max_compat_pvr)
    144{
    145    PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
    146
    147#if !defined(CONFIG_USER_ONLY)
    148    g_assert(cpu->vhyp);
    149#endif
    150
    151    return pcc_compat(pcc, compat_pvr, min_compat_pvr, max_compat_pvr);
    152}
    153
    154bool ppc_type_check_compat(const char *cputype, uint32_t compat_pvr,
    155                           uint32_t min_compat_pvr, uint32_t max_compat_pvr)
    156{
    157    PowerPCCPUClass *pcc = POWERPC_CPU_CLASS(object_class_by_name(cputype));
    158    return pcc_compat(pcc, compat_pvr, min_compat_pvr, max_compat_pvr);
    159}
    160
    161int ppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr, Error **errp)
    162{
    163    const CompatInfo *compat = compat_by_pvr(compat_pvr);
    164    CPUPPCState *env = &cpu->env;
    165    PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
    166    uint64_t pcr;
    167
    168    if (!compat_pvr) {
    169        pcr = 0;
    170    } else if (!compat) {
    171        error_setg(errp, "Unknown compatibility PVR 0x%08"PRIx32, compat_pvr);
    172        return -EINVAL;
    173    } else if (!ppc_check_compat(cpu, compat_pvr, 0, 0)) {
    174        error_setg(errp, "Compatibility PVR 0x%08"PRIx32" not valid for CPU",
    175                   compat_pvr);
    176        return -EINVAL;
    177    } else {
    178        pcr = compat->pcr;
    179    }
    180
    181    cpu_synchronize_state(CPU(cpu));
    182
    183    if (kvm_enabled() && cpu->compat_pvr != compat_pvr) {
    184        int ret = kvmppc_set_compat(cpu, compat_pvr);
    185        if (ret < 0) {
    186            error_setg_errno(errp, -ret,
    187                             "Unable to set CPU compatibility mode in KVM");
    188            return ret;
    189        }
    190    }
    191
    192    cpu->compat_pvr = compat_pvr;
    193    env->spr[SPR_PCR] = pcr & pcc->pcr_mask;
    194    return 0;
    195}
    196
    197typedef struct {
    198    uint32_t compat_pvr;
    199    Error **errp;
    200    int ret;
    201} SetCompatState;
    202
    203static void do_set_compat(CPUState *cs, run_on_cpu_data arg)
    204{
    205    PowerPCCPU *cpu = POWERPC_CPU(cs);
    206    SetCompatState *s = arg.host_ptr;
    207
    208    s->ret = ppc_set_compat(cpu, s->compat_pvr, s->errp);
    209}
    210
    211int ppc_set_compat_all(uint32_t compat_pvr, Error **errp)
    212{
    213    CPUState *cs;
    214
    215    CPU_FOREACH(cs) {
    216        SetCompatState s = {
    217            .compat_pvr = compat_pvr,
    218            .errp = errp,
    219            .ret = 0,
    220        };
    221
    222        run_on_cpu(cs, do_set_compat, RUN_ON_CPU_HOST_PTR(&s));
    223
    224        if (s.ret < 0) {
    225            return s.ret;
    226        }
    227    }
    228
    229    return 0;
    230}
    231
    232int ppc_compat_max_vthreads(PowerPCCPU *cpu)
    233{
    234    const CompatInfo *compat = compat_by_pvr(cpu->compat_pvr);
    235    int n_threads = CPU(cpu)->nr_threads;
    236
    237    if (cpu->compat_pvr) {
    238        g_assert(compat);
    239        n_threads = MIN(n_threads, compat->max_vthreads);
    240    }
    241
    242    return n_threads;
    243}
    244
    245static void ppc_compat_prop_get(Object *obj, Visitor *v, const char *name,
    246                                void *opaque, Error **errp)
    247{
    248    uint32_t compat_pvr = *((uint32_t *)opaque);
    249    const char *value;
    250
    251    if (!compat_pvr) {
    252        value = "";
    253    } else {
    254        const CompatInfo *compat = compat_by_pvr(compat_pvr);
    255
    256        g_assert(compat);
    257
    258        value = compat->name;
    259    }
    260
    261    visit_type_str(v, name, (char **)&value, errp);
    262}
    263
    264static void ppc_compat_prop_set(Object *obj, Visitor *v, const char *name,
    265                                void *opaque, Error **errp)
    266{
    267    char *value;
    268    uint32_t compat_pvr;
    269
    270    if (!visit_type_str(v, name, &value, errp)) {
    271        return;
    272    }
    273
    274    if (strcmp(value, "") == 0) {
    275        compat_pvr = 0;
    276    } else {
    277        int i;
    278        const CompatInfo *compat = NULL;
    279
    280        for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
    281            if (strcmp(value, compat_table[i].name) == 0) {
    282                compat = &compat_table[i];
    283                break;
    284
    285            }
    286        }
    287
    288        if (!compat) {
    289            error_setg(errp, "Invalid compatibility mode \"%s\"", value);
    290            goto out;
    291        }
    292        compat_pvr = compat->pvr;
    293    }
    294
    295    *((uint32_t *)opaque) = compat_pvr;
    296
    297out:
    298    g_free(value);
    299}
    300
    301void ppc_compat_add_property(Object *obj, const char *name,
    302                             uint32_t *compat_pvr, const char *basedesc)
    303{
    304    gchar *namesv[ARRAY_SIZE(compat_table) + 1];
    305    gchar *names, *desc;
    306    int i;
    307
    308    object_property_add(obj, name, "string",
    309                        ppc_compat_prop_get, ppc_compat_prop_set, NULL,
    310                        compat_pvr);
    311
    312    for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
    313        /*
    314         * Have to discard const here, because g_strjoinv() takes
    315         * (gchar **), not (const gchar **) :(
    316         */
    317        namesv[i] = (gchar *)compat_table[i].name;
    318    }
    319    namesv[ARRAY_SIZE(compat_table)] = NULL;
    320
    321    names = g_strjoinv(", ", namesv);
    322    desc = g_strdup_printf("%s. Valid values are %s.", basedesc, names);
    323    object_property_set_description(obj, name, desc);
    324
    325    g_free(names);
    326    g_free(desc);
    327}