https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org/thread/BIJZP4IZL34RDKPCSBMKLFZZQIKVJ7XU/

tree:   https://github.com/alibaba/cloud-kernel.git linux-next
head:   c3ac3c331d6cc495be9603404799c061d71af44c
commit: 671b4f344c85141b26aefca5aa012a58e8f729d1 [11000/12249] virtio-balloon: add support for providing free page reports to host
config: x86_64-randconfig-s021-20200928 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.2-201-g24bdaac6-dirty
        # https://github.com/alibaba/cloud-kernel/commit/671b4f344c85141b26aefca5aa012a58e8f729d1
        git remote add alibaba-cloud https://github.com/alibaba/cloud-kernel.git
        git fetch --no-tags alibaba-cloud linux-next
        git checkout 671b4f344c85141b26aefca5aa012a58e8f729d1
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>


sparse warnings: (new ones prefixed by >>)

>> drivers/virtio/virtio_balloon.c:163:5: sparse: sparse: symbol 'virtballoon_free_page_report' was not declared. Should it be static?
   drivers/virtio/virtio_balloon.c:163:5: warning: no previous prototype for 'virtballoon_free_page_report' [-Wmissing-prototypes]
     163 | int virtballoon_free_page_report(struct page_reporting_dev_info *pr_dev_info,
         |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

Please review and possibly fold the followup patch.

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org