DMESG_MAX_LINE_LEN
line_buff = kzalloc(DMESG_MAX_LINE_LEN, GFP_ATOMIC);
strscpy(line_buff, prefix, DMESG_MAX_LINE_LEN - MIN_SPACE - 2);
DMESG_MAX_LINE_LEN - line_pos);
if ((line_pos + MIN_SPACE) >= DMESG_MAX_LINE_LEN) {