port-i386/42787: short assember program panics system

[mark%ecs.vuw.ac.nz@localhost]

>Number:         42787
>Category:       port-i386
>Synopsis:       short assember program panics system
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    port-i386-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Feb 11 07:20:00 +0000 2010
>Originator:     Mark Davies
>Release:        NetBSD 5.0_STABLE
>Organization:
ECS, Victoria Uni. of Wellington, New Zealand.
>Environment:
        
        
System: NetBSD turakirae.ecs.vuw.ac.nz 5.0_STABLE NetBSD 5.0_STABLE 
(ECS_WORKSTATION) #6: Fri Jan 29 14:49:01 NZDT 2010 
mark%turakirae.ecs.vuw.ac.nz@localhost:/local/SAVE/build.obj/src/work/5/src/sys/arch/i386/compile/ECS_WORKSTATION
 i386
Architecture: i386
Machine: i386
>Description:
        While looking at assembler tutorials for use in a course one of our
        lecturers was working through the examples in
        http://www.muppetlabs.com/~breadbox/software/tiny/teensy.html
        Running the 4 line assembler program from page 5 causes the machine
        to panic with

kernel: supervisor trap page fault, code = 0
stopped in pid 1180.1(a.out) at netbsd:alltraps+0x9d: mov 0(%esp),%gs

        
>How-To-Repeat:
        Create a file "tiny.asm" with this content:

; tiny.asm
BITS 32
GLOBAL _start
SECTION .text
_start:
        mov     eax, 1
        mov     ebx, 42
        int     0x80


Build and run with
      nasm -f elf tiny.asm
      ld -s tiny.o
      ./a.out

Watch the machine fall over.
        
>Fix:
        Don't know.
        

>Unformatted: