tree: https://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git hyperv-next head: f69bc337f7bdb619619af0a1caf951b1feeccb08 commit: 951d33f2d785c6dc721db44bb8c00ceaa4eeb2d6 [16/27] scsi: storvsc: Re-init stor_chns when a channel interrupt is re-assigned config: x86_64-randconfig-a011-20200519 (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 135b877874fae96b4372c8a3fbfaa8ff44ff86e3) reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu git checkout 951d33f2d785c6dc721db44bb8c00ceaa4eeb2d6 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>, old ones prefixed by <<): void storvsc_change_target_cpu(struct vmbus_channel *channel, u32 old, u32 new) ^ drivers/scsi/storvsc_drv.c:624:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void storvsc_change_target_cpu(struct vmbus_channel *channel, u32 old, u32 new) ^ static 1 warning generated. vim +/storvsc_change_target_cpu +624 drivers/scsi/storvsc_drv.c 623 625 { 626 struct storvsc_device *stor_device; 627 struct vmbus_channel *cur_chn; 628 bool old_is_alloced = false; 629 struct hv_device *device; 630 unsigned long flags; 631 int cpu; 632 633 device = channel->primary_channel ? 634 channel->primary_channel->device_obj 635 : channel->device_obj; 636 stor_device = get_out_stor_device(device); 637 if (!stor_device) 638 return; 639 640 /* See storvsc_do_io() -> get_og_chn(). */ 641 spin_lock_irqsave(&device->channel->lock, flags); 642 643 /* 644 * Determines if the storvsc device has other channels assigned to 645 * the "old" CPU to update the alloced_cpus mask and the stor_chns 646 * array. 647 */ 648 if (device->channel != channel && device->channel->target_cpu == old) { 649 cur_chn = device->channel; 650 old_is_alloced = true; 651 goto old_is_alloced; 652 } 653 list_for_each_entry(cur_chn, &device->channel->sc_list, sc_list) { 654 if (cur_chn == channel) 655 continue; 656 if (cur_chn->target_cpu == old) { 657 old_is_alloced = true; 658 goto old_is_alloced; 659 } 660 } 661 662 old_is_alloced: 663 if (old_is_alloced) 664 WRITE_ONCE(stor_device->stor_chns[old], cur_chn); 665 else 666 cpumask_clear_cpu(old, &stor_device->alloced_cpus); 667 668 /* "Flush" the stor_chns array. */ 669 for_each_possible_cpu(cpu) { 670 if (stor_device->stor_chns[cpu] && !cpumask_test_cpu( 671 cpu, &stor_device->alloced_cpus)) 672 WRITE_ONCE(stor_device->stor_chns[cpu], NULL); 673 } 674 675 WRITE_ONCE(stor_device->stor_chns[new], channel); 676 cpumask_set_cpu(new, &stor_device->alloced_cpus); 677 678 spin_unlock_irqrestore(&device->channel->lock, flags); 679 } 680 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org