kernel_add_identity_map
kernel_add_identity_map((unsigned long)_head, (unsigned long)_end);
kernel_add_identity_map((unsigned long)boot_params_ptr,
kernel_add_identity_map(cmdline, cmdline + COMMAND_LINE_SIZE);
kernel_add_identity_map(sd_addr, sd_addr + sizeof(*sd) + sd->len);
kernel_add_identity_map(address, end);
extern void kernel_add_identity_map(unsigned long start, unsigned long end);
kernel_add_identity_map(cc_info_pa, cc_info_pa + sizeof(*cc_info));
kernel_add_identity_map(cc_info->cpuid_phys, cc_info->cpuid_phys + cc_info->cpuid_len);