kern/145024: [linux] kernel crash by linux.ko module with nooptions COMPAT_FREEBSD32

[arundel at FreeBSD.org]

Old Synopsis: [linux] [panic] kernel crash by linux.ko module with nooptions COMPAT_FREEBSD32
New Synopsis: [linux] kernel crash by linux.ko module with nooptions COMPAT_FREEBSD32

State-Changed-From-To: open->analyzed
State-Changed-By: arundel
State-Changed-When: Sun Jan 30 18:13:13 UTC 2011
State-Changed-Why: 
We have two possibilities in order to fix this issue:

1) Add something like the following somewhere in sys/amd/linux32:

   #ifndef COMPAT_FREEBSD32
   #error "linux emulation requires COMPAT_FREEBSD32 \
	   option for non 32 bit architectures"
   #endif

2) Find a way to avoid the freebsd32_exec_copyin_args() call in
   linux32_machdep.c. I believe this is the only place in the sys/amd/linux32
   code that depends on sys/amd64/ia32 code.

NB: I've removed the panic tag from this PR. I was able to reproduce the issue,
    however a panic didn't occur. The problem is that
    freebsd32_exec_copyin_args() wasn't compiled into the kernel and loading the
    linux kernel module thus fails.

http://www.freebsd.org/cgi/query-pr.cgi?pr=145024