[Qemu-devel] [6453] x86: Issue reset on triple faults (Jan Kiszka)

[Anthony Liguori <anthony@codemonkey.ws>]

Revision: 6453
          http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=6453
Author:   aliguori
Date:     2009-01-26 19:54:36 +0000 (Mon, 26 Jan 2009)

Log Message:
-----------
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>

Modified Paths:
--------------
    trunk/target-i386/op_helper.c

Modified: trunk/target-i386/op_helper.c
===================================================================
--- trunk/target-i386/op_helper.c	2009-01-26 19:54:31 UTC (rev 6452)
+++ trunk/target-i386/op_helper.c	2009-01-26 19:54:36 UTC (rev 6453)
@@ -1251,6 +1251,9 @@
     }
 }
 
+/* This should come from sysemu.h - if we could include it here... */
+void qemu_system_reset_request(void);
+
 /*
  * Check nested exceptions and change to double or triple fault if
  * needed. It should only be called, if this is not an interrupt.
@@ -1267,9 +1270,19 @@
     qemu_log_mask(CPU_LOG_INT, "check_exception old: 0x%x new 0x%x\n",
                 env->old_exception, intno);
 
-    if (env->old_exception == EXCP08_DBLE)
-        cpu_abort(env, "triple fault");
+#if !defined(CONFIG_USER_ONLY)
+    if (env->old_exception == EXCP08_DBLE) {
+        if (env->hflags & HF_SVMI_MASK)
+            helper_vmexit(SVM_EXIT_SHUTDOWN, 0); /* does not return */
 
+        if (loglevel & CPU_LOG_RESET)
+            fprintf(logfile, "Triple fault\n");
+
+        qemu_system_reset_request();
+        return EXCP_HLT;
+    }
+#endif
+
     if ((first_contributory && second_contributory)
         || (env->old_exception == EXCP0E_PAGE &&
             (second_contributory || (intno == EXCP0E_PAGE)))) {