Hi Wei, I love your patch! Perhaps something to improve: [auto build test WARNING on tip/x86/core] [also build test WARNING on asm-generic/master iommu/next tip/timers/core pci/next linus/master v5.10-rc2 next-20201105] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Wei-Liu/Introducing-Linux-root-p... base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 238c91115cd05c71447ea071624a4c9fe661f970 config: i386-randconfig-r002-20201104 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce (this is a W=1 build): # https://github.com/0day-ci/linux/commit/83c03b4e30e729a77688b8c0ffeffa2a5... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Wei-Liu/Introducing-Linux-root-partition-support-for-Microsoft-Hypervisor/20201106-010058 git checkout 83c03b4e30e729a77688b8c0ffeffa2a555dcce7 # save the attached .config to linux build tree make W=1 ARCH=i386 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 >>): 341 | void __init hv_get_partition_id(void) | ^~~~~~~~~~~~~~~~~~~ vim +/hv_get_partition_id +341 arch/x86/hyperv/hv_init.c 340 342 { 343 struct hv_get_partition_id *output_page; 344 u16 status; 345 unsigned long flags; 346 347 local_irq_save(flags); 348 output_page = *this_cpu_ptr(hyperv_pcpu_output_arg); 349 status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page) & 350 HV_HYPERCALL_RESULT_MASK; 351 if (status != HV_STATUS_SUCCESS) 352 pr_err("Failed to get partition ID: %d\n", status); 353 else 354 hv_current_partition_id = output_page->partition_id; 355 local_irq_restore(flags); 356 357 /* No point in proceeding if this failed */ 358 BUG_ON(status != HV_STATUS_SUCCESS); 359 } 360 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org