[Qemu-devel] Re: strange crash on FreeBSD-current/amd64 (pointer truncation?)

[Juergen Lock]

On Wed, Jan 24, 2007 at 09:00:19PM +0100, Juergen Lock wrote:
> Hi!
> 
>  I got a report of qemu segfaulting here on FreeBSD-current/amd64:
> 
> > #0  main_loop () at 
> > /usr/ports-cvs/emulators/qemu/work/qemu-snapshot-2007-01-11_05/vl.c:6125
> > 6125                    env = env->next_cpu;
> > [New Thread 0x801e10190 (LWP 100214)]
> > (gdb) print env
> > $1 = (CPUX86State *) 0xac10000
> > (gdb) print first_cpu
> > $2 = (CPUX86State *) 0x80ac10000

Ok Jung-uk Kim found the following fix: (Thanx!)

--- qemu/cpu-exec.c.orig        Wed Jan 31 16:58:03 2007
+++ qemu/cpu-exec.c     Wed Jan 31 17:08:11 2007
@@ -226,9 +226,9 @@
 
 int cpu_exec(CPUState *env1)
 {
-    int saved_T0, saved_T1;
+    long saved_T0, saved_T1;
 #if defined(reg_T2)
-    int saved_T2;
+    long saved_T2;
 #endif
     CPUState *saved_env;
 #if defined(TARGET_I386)

 It's funny that the upper half of rbx (which holds env above)
apparently only gets spilled on FreeBSD-current, even tho on amd64
T0 (== AREG1 == rbx) certainly doesn't fit into an int...

        Juergen