tree: https://github.com/intel/tdx.git guest head: 41fe88a1b3c28543f49fa6ed9e0e9b6650ed7614 commit: e429db7ac5ebc20d80a407ff29424e5bb710d057 [108/144] x86/tdx: Enable direct iomap MMIO optimizations config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20211208/202112080635.7JcdsSvJ-lk...) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://github.com/intel/tdx/commit/e429db7ac5ebc20d80a407ff29424e5bb710d057 git remote add intel-tdx https://github.com/intel/tdx.git git fetch --no-tags intel-tdx guest git checkout e429db7ac5ebc20d80a407ff29424e5bb710d057 # save the config file to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): arch/x86/kernel/tdx.c:269:5: warning: no previous prototype for 'tdx_hcall_set_notify_intr' [-Wmissing-prototypes] 269 | int tdx_hcall_set_notify_intr(u8 vector) | ^~~~~~~~~~~~~~~~~~~~~~~~~ arch/x86/kernel/tdx.c:492:14: warning: no previous prototype for 'tdx_write_msr' [-Wmissing-prototypes] 492 | void notrace tdx_write_msr(unsigned int msr, u32 low, u32 high) | ^~~~~~~~~~~~~ 714 | unsigned long tdx_mmio_readq(void __iomem *addr) | ^~~~~~~~~~~~~~ vim +/tdx_mmio_readq +714 arch/x86/kernel/tdx.c 713 715 { 716 unsigned long val; 717 718 if (tdx_virt_mmio(8, false, (unsigned long)addr, &val)) 719 return 0xffffffffffffffff; 720 return val; 721 } 722 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org