Hi, Simon
> I compiled the kernel two times, one time with the original code and
> one time with
> #define container_of(ptr, type, member) ({			\
> 	(type *)( (char *)ptr - offsetof(type,member) );})
try with following version:
#define container_of(ptr, type, member) ({ \
	(type *)((char *)(ptr) - offsetof(type, member));})