Subject: Re: Cross-building
To: None <>
From: Mark Kettenis <>
List: port-amd64
Date: 10/22/2003 23:04:36
   Date: Tue, 21 Oct 2003 13:52:27 +0200
   From: Frank van der Linden <>

   On Mon, Oct 20, 2003 at 11:43:26PM +0200, Mark Kettenis wrote:
   > The behaviour has changed.  The SIGALRM test pass now, but
   > unfortunately there is a test further down in signal.exp that hangs
   > the machine; I can't ping the machine and the console is dead.  I'll
   > need to investigate this, since I don't even know exactlt what test is
   > failing.

   Let me know if I can do anything to help, or how to reproduce the
   problem, so that I can debug the possible kernel issue lurking here.
   I appreciate your work on this.

I have experimented a bit and have pin-pointed the test that crashes
the machine.  The following scenario can be used to reproduce the problem:

$ gdb sandbox/virgin-gdb/obj/gdb/testsuite/gdb.base/run 
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This GDB was configured as "x86_64--netbsd"...
(gdb) b main
Breakpoint 1 at 0x400a9f: file ../../../src/gdb/testsuite/gdb.base/run.c, line 59.
(gdb) r
Starting program: /home/kettenis/sandbox/virgin-gdb/obj/gdb/testsuite/gdb.base/run 

Breakpoint 1, main (argc=1, argv=0x7f7ffffffa48, envp=0x7f7ffffffa58)
    at ../../../src/gdb/testsuite/gdb.base/run.c:59
59      ../../../src/gdb/testsuite/gdb.base/run.c: No such file or directory.
        in ../../../src/gdb/testsuite/gdb.base/run.c
(gdb) signal 5
Continuing with signal SIGTRAP.

At this point the machine crashes.  Sometimes I get a message on the
console that starts with:

fatal protection fault in supervisor mode
rip ffffffff80100594

which corresponds to the 

   movq    %rcx,%cr0

instruction in locore.S:switch_exited.

The system call that crashes the machine is:

  ptrace (PT_CONTINUE, PID, 1, SIGTRAP);

I also tried a few other signals, and it seems that only those signals
whose default behaviour is to produce a core dump (i.e. SIGQUIT,
produce the crash.

Hope this bit of info helps.