Hi, When building ACM into xen, I found this error: acm_core.c: In function ¡®acm_init¡¯: acm_core.c:283: error: ¡®policy_buffer¡¯ undeclared (first use in this function) acm_core.c:283: error: (Each undeclared identifier is reported only once acm_core.c:283: error: for each function it appears in.) acm_core.c:283: error: ¡®policy_size¡¯ undeclared (first use in this function) cc1: warnings being treated as errors acm_core.c:319: warning: implicit declaration of function ¡®register_xsm¡¯ acm_core.c: At top level: acm_core.c:325: warning: data definition has no type or storage class acm_core.c:325: warning: type defaults to ¡®int¡¯ in declaration of ¡®xsm_initcall¡¯ acm_core.c:325: warning: parameter names (without types) in function declaration make[4]: *** [acm_core.o] Error 1 make[4]: Leaving directory `/xen/xen-3.4.2/xen/xsm/acm' make[3]: *** [acm/built_in.o] Error 2 make[3]: Leaving directory `/xen/xen-3.4.2/xen/xsm' make[2]: *** [/xen/xen-3.4.2/xen/xsm/built_in.o] Error 2 make[2]: Leaving directory `/xen/xen-3.4.2/xen/arch/x86' make[1]: *** [/xen/xen-3.4.2/xen/xen] Error 2 make[1]: Leaving directory `/xen/xen-3.4.2/xen' make: *** [build] Error 2 I've checked acm_core.c , and I didn't find the declaration of "policy_buffer" and "policy_size". Could anyone help? OS: Ubuntu Server 8.04 XEN: 3.4.2 thx! 2010-09-02 Best wishes Ruozeng W