Hi David,

Does it make sense to build this sample when cross compiling?

The reason I ask is that it has been breaking the linux-next build of
allmodconfig for a while now, with:

  HOSTCC  samples/kdbus/kdbus-workers
samples/kdbus/kdbus-workers.c: In function ‘prime_new’:
samples/kdbus/kdbus-workers.c:934:18: error: ‘__NR_memfd_create’ undeclared (first use in this function)
  p->fd = syscall(__NR_memfd_create, "prime-area", MFD_CLOEXEC);
                  ^
samples/kdbus/kdbus-workers.c:934:18: note: each undeclared identifier is reported only once for each function it appears in
scripts/Makefile.host:91: recipe for target 'samples/kdbus/kdbus-workers' failed
make[2]: *** [samples/kdbus/kdbus-workers] Error 1

http://kisskb.ellerman.id.au/kisskb/buildresult/12473453/

We recently made some changes to skip other sample/test programs when
cross compiling in mainline 65f6f092a6987 and f59514b6a8c5ca6dd and
6a407a81a9abcf.  Maybe it makes sense to do the same here?

Paul.