cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

cpu_loop.c (5685B)


      1/*
      2 *  qemu user cpu loop
      3 *
      4 *  Copyright (c) 2003-2008 Fabrice Bellard
      5 *
      6 *  This program is free software; you can redistribute it and/or modify
      7 *  it under the terms of the GNU General Public License as published by
      8 *  the Free Software Foundation; either version 2 of the License, or
      9 *  (at your option) any later version.
     10 *
     11 *  This program 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
     14 *  GNU General Public License for more details.
     15 *
     16 *  You should have received a copy of the GNU General Public License
     17 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
     18 */
     19
     20#include "qemu/osdep.h"
     21#include "qemu-common.h"
     22#include "qemu.h"
     23#include "user-internals.h"
     24#include "cpu_loop-common.h"
     25#include "signal-common.h"
     26
     27/* s390x masks the fault address it reports in si_addr for SIGSEGV and SIGBUS */
     28#define S390X_FAIL_ADDR_MASK -4096LL
     29
     30static int get_pgm_data_si_code(int dxc_code)
     31{
     32    switch (dxc_code) {
     33    /* Non-simulated IEEE exceptions */
     34    case 0x80:
     35        return TARGET_FPE_FLTINV;
     36    case 0x40:
     37        return TARGET_FPE_FLTDIV;
     38    case 0x20:
     39    case 0x28:
     40    case 0x2c:
     41        return TARGET_FPE_FLTOVF;
     42    case 0x10:
     43    case 0x18:
     44    case 0x1c:
     45        return TARGET_FPE_FLTUND;
     46    case 0x08:
     47    case 0x0c:
     48        return TARGET_FPE_FLTRES;
     49    }
     50    /*
     51     * Non-IEEE and simulated IEEE:
     52     * Includes compare-and-trap, quantum exception, etc.
     53     * Simulated IEEE are included here to match current
     54     * s390x linux kernel.
     55     */
     56    return 0;
     57}
     58
     59void cpu_loop(CPUS390XState *env)
     60{
     61    CPUState *cs = env_cpu(env);
     62    int trapnr, n, sig;
     63    target_siginfo_t info;
     64    target_ulong addr;
     65    abi_long ret;
     66
     67    while (1) {
     68        cpu_exec_start(cs);
     69        trapnr = cpu_exec(cs);
     70        cpu_exec_end(cs);
     71        process_queued_cpu_work(cs);
     72
     73        switch (trapnr) {
     74        case EXCP_INTERRUPT:
     75            /* Just indicate that signals should be handled asap.  */
     76            break;
     77
     78        case EXCP_SVC:
     79            n = env->int_svc_code;
     80            if (!n) {
     81                /* syscalls > 255 */
     82                n = env->regs[1];
     83            }
     84            env->psw.addr += env->int_svc_ilen;
     85            ret = do_syscall(env, n, env->regs[2], env->regs[3],
     86                             env->regs[4], env->regs[5],
     87                             env->regs[6], env->regs[7], 0, 0);
     88            if (ret == -TARGET_ERESTARTSYS) {
     89                env->psw.addr -= env->int_svc_ilen;
     90            } else if (ret != -TARGET_QEMU_ESIGRETURN) {
     91                env->regs[2] = ret;
     92            }
     93            break;
     94
     95        case EXCP_DEBUG:
     96            sig = TARGET_SIGTRAP;
     97            n = TARGET_TRAP_BRKPT;
     98            /*
     99             * For SIGTRAP the PSW must point after the instruction, which it
    100             * already does thanks to s390x_tr_tb_stop(). si_addr doesn't need
    101             * to be filled.
    102             */
    103            addr = 0;
    104            goto do_signal;
    105        case EXCP_PGM:
    106            n = env->int_pgm_code;
    107            switch (n) {
    108            case PGM_OPERATION:
    109            case PGM_PRIVILEGED:
    110                sig = TARGET_SIGILL;
    111                n = TARGET_ILL_ILLOPC;
    112                goto do_signal_pc;
    113            case PGM_PROTECTION:
    114            case PGM_ADDRESSING:
    115                sig = TARGET_SIGSEGV;
    116                /* XXX: check env->error_code */
    117                n = TARGET_SEGV_MAPERR;
    118                addr = env->__excp_addr & S390X_FAIL_ADDR_MASK;
    119                goto do_signal;
    120            case PGM_EXECUTE:
    121            case PGM_SPECIFICATION:
    122            case PGM_SPECIAL_OP:
    123            case PGM_OPERAND:
    124            do_sigill_opn:
    125                sig = TARGET_SIGILL;
    126                n = TARGET_ILL_ILLOPN;
    127                goto do_signal_pc;
    128
    129            case PGM_FIXPT_OVERFLOW:
    130                sig = TARGET_SIGFPE;
    131                n = TARGET_FPE_INTOVF;
    132                goto do_signal_pc;
    133            case PGM_FIXPT_DIVIDE:
    134                sig = TARGET_SIGFPE;
    135                n = TARGET_FPE_INTDIV;
    136                goto do_signal_pc;
    137
    138            case PGM_DATA:
    139                n = (env->fpc >> 8) & 0xff;
    140                if (n == 0) {
    141                    goto do_sigill_opn;
    142                }
    143
    144                sig = TARGET_SIGFPE;
    145                n = get_pgm_data_si_code(n);
    146                goto do_signal_pc;
    147
    148            default:
    149                fprintf(stderr, "Unhandled program exception: %#x\n", n);
    150                cpu_dump_state(cs, stderr, 0);
    151                exit(EXIT_FAILURE);
    152            }
    153            break;
    154
    155        do_signal_pc:
    156            addr = env->psw.addr;
    157            /*
    158             * For SIGILL and SIGFPE the PSW must point after the instruction.
    159             */
    160            env->psw.addr += env->int_pgm_ilen;
    161        do_signal:
    162            info.si_signo = sig;
    163            info.si_errno = 0;
    164            info.si_code = n;
    165            info._sifields._sigfault._addr = addr;
    166            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
    167            break;
    168
    169        case EXCP_ATOMIC:
    170            cpu_exec_step_atomic(cs);
    171            break;
    172        default:
    173            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
    174            cpu_dump_state(cs, stderr, 0);
    175            exit(EXIT_FAILURE);
    176        }
    177        process_pending_signals (env);
    178    }
    179}
    180
    181void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
    182{
    183    int i;
    184    for (i = 0; i < 16; i++) {
    185        env->regs[i] = regs->gprs[i];
    186    }
    187    env->psw.mask = regs->psw.mask;
    188    env->psw.addr = regs->psw.addr;
    189}