vbg_debug
vbg_debug("VBG_IOCTL_HGCM_CALL: hdr.size_in %d required size is %zd\n",
vbg_debug("VBG_IOCTL_HGCM_CALL: INVALID handle. u32Client=%#08x\n",
vbg_debug("%s: too much output data %zu > %zu\n",
VBG_LOG(vbg_debug, pr_debug);
__printf(1, 2) void vbg_debug(const char *fmt, ...);