Commit f55761a0c46583f4faf1d7595f4f41b35b15508b

Authored by aliguori
1 parent eca1bdf4

x86: Issue reset on triple faults (Jan Kiszka)

As discussed a few times on this list: A triple fault causes a system
reset on x86, and some guests make use of this (e.g. 386BSD). To keep
the chance of tracing unexpected resets, log them if CPU_LOG_RESET is
set.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6453 c046a42c-6fe2-441c-8c8c-71466251a162
Showing 1 changed file with 15 additions and 2 deletions
target-i386/op_helper.c
... ... @@ -1251,6 +1251,9 @@ void do_interrupt(int intno, int is_int, int error_code,
1251 1251 }
1252 1252 }
1253 1253  
  1254 +/* This should come from sysemu.h - if we could include it here... */
  1255 +void qemu_system_reset_request(void);
  1256 +
1254 1257 /*
1255 1258 * Check nested exceptions and change to double or triple fault if
1256 1259 * needed. It should only be called, if this is not an interrupt.
... ... @@ -1267,8 +1270,18 @@ static int check_exception(int intno, int *error_code)
1267 1270 qemu_log_mask(CPU_LOG_INT, "check_exception old: 0x%x new 0x%x\n",
1268 1271 env->old_exception, intno);
1269 1272  
1270   - if (env->old_exception == EXCP08_DBLE)
1271   - cpu_abort(env, "triple fault");
  1273 +#if !defined(CONFIG_USER_ONLY)
  1274 + if (env->old_exception == EXCP08_DBLE) {
  1275 + if (env->hflags & HF_SVMI_MASK)
  1276 + helper_vmexit(SVM_EXIT_SHUTDOWN, 0); /* does not return */
  1277 +
  1278 + if (loglevel & CPU_LOG_RESET)
  1279 + fprintf(logfile, "Triple fault\n");
  1280 +
  1281 + qemu_system_reset_request();
  1282 + return EXCP_HLT;
  1283 + }
  1284 +#endif
1272 1285  
1273 1286 if ((first_contributory && second_contributory)
1274 1287 || (env->old_exception == EXCP0E_PAGE &&
... ...