Comment 14 for bug 455067

Reproducer, on i386 kernel, with vm.mmap_min_addr=0, thanks to Bart Oldeman:

Create a debug script file (e.g. debug.scr) in ~/.dosemu/drive_c, that is, dosemu's c:\

---snip---
a
nop
nop
int 3

t
g
q
---snip---

Then run
  dosemu "debug < debug.scr"
This will get both int1 and int3 active.

Try it a few times, it should trigger the bug in "dmesg".