Re: [PATCH v11 12/14] s390/vfio-ap: handle host AP config change notification

[Tony Krowiak <akrowiak@linux.ibm.com>]

On 10/22/20 5:17 PM, kernel test robot wrote:
> Hi Tony,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on s390/features]
> [also build test WARNING on linus/master next-20201022]
> [cannot apply to kvms390/next linux/master v5.9]
> [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/Tony-Krowiak/s390-vfio-ap-dynamic-configuration-support/20201023-011543
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git features
> config: s390-allyesconfig (attached as .config)
> compiler: s390-linux-gcc (GCC) 9.3.0
> reproduce (this is a W=1 build):
>          wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>          chmod +x ~/bin/make.cross
>          # https://github.com/0day-ci/linux/commit/32786ef6d4ba3703d993a8894ea1d763785fd3a4
>          git remote add linux-review https://github.com/0day-ci/linux
>          git fetch --no-tags linux-review Tony-Krowiak/s390-vfio-ap-dynamic-configuration-support/20201023-011543
>          git checkout 32786ef6d4ba3703d993a8894ea1d763785fd3a4
>          # save the attached .config to linux build tree
>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=s390
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
>     drivers/s390/crypto/vfio_ap_ops.c:1316:5: warning: no previous prototype for 'vfio_ap_mdev_reset_queue' [-Wmissing-prototypes]
>      1316 | int vfio_ap_mdev_reset_queue(unsigned int apid, unsigned int apqi,
>           |     ^~~~~~~~~~~~~~~~~~~~~~~~
>     drivers/s390/crypto/vfio_ap_ops.c:1568:6: warning: no previous prototype for 'vfio_ap_mdev_hot_unplug_queue' [-Wmissing-prototypes]
>      1568 | void vfio_ap_mdev_hot_unplug_queue(struct vfio_ap_queue *q)
>           |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>     drivers/s390/crypto/vfio_ap_ops.c: In function 'vfio_ap_mdev_on_cfg_remove':
>>> drivers/s390/crypto/vfio_ap_ops.c:1777:7: warning: variable 'unassigned' set but not used [-Wunused-but-set-variable]
>      1777 |  bool unassigned = false;
>           |       ^~~~~~~~~~
>     drivers/s390/crypto/vfio_ap_ops.c: At top level:
>>> drivers/s390/crypto/vfio_ap_ops.c:1813:6: warning: no previous prototype for 'vfio_ap_mdev_on_cfg_add' [-Wmissing-prototypes]
>      1813 | void vfio_ap_mdev_on_cfg_add(void)
>           |      ^~~~~~~~~~~~~~~~~~~~~~~

Needs to be static, will fix.

>     In file included from drivers/s390/crypto/vfio_ap_ops.c:11:
>     In function 'memcpy',
>         inlined from 'vfio_ap_mdev_unassign_apids' at drivers/s390/crypto/vfio_ap_ops.c:1655:3,
>         inlined from 'vfio_ap_mdev_on_cfg_remove' at drivers/s390/crypto/vfio_ap_ops.c:1800:8,
>         inlined from 'vfio_ap_on_cfg_changed' at drivers/s390/crypto/vfio_ap_ops.c:1836:2:
>     include/linux/string.h:402:4: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter
>       402 |    __read_overflow2();
>           |    ^~~~~~~~~~~~~~~~~~

Will replace memcpy with bitmap_copy.

>
> vim +/unassigned +1777 drivers/s390/crypto/vfio_ap_ops.c
>
>    1774	
>    1775	static void vfio_ap_mdev_on_cfg_remove(void)
>    1776	{
>> 1777		bool unassigned = false;
>    1778		int ap_remove, aq_remove;
>    1779		struct ap_matrix_mdev *matrix_mdev;
>    1780		DECLARE_BITMAP(apid_rem, AP_DEVICES);
>    1781		DECLARE_BITMAP(apqi_rem, AP_DOMAINS);
>    1782		unsigned long *cur_apm, *cur_aqm, *prev_apm, *prev_aqm;
>    1783	
>    1784		cur_apm = (unsigned long *)matrix_dev->config_info.apm;
>    1785		cur_aqm = (unsigned long *)matrix_dev->config_info.aqm;
>    1786		prev_apm = (unsigned long *)matrix_dev->config_info_prev.apm;
>    1787		prev_aqm = (unsigned long *)matrix_dev->config_info_prev.aqm;
>    1788	
>    1789		ap_remove = bitmap_andnot(apid_rem, prev_apm, cur_apm, AP_DEVICES);
>    1790		aq_remove = bitmap_andnot(apqi_rem, prev_aqm, cur_aqm, AP_DOMAINS);
>    1791	
>    1792		if (!ap_remove && !aq_remove)
>    1793			return;
>    1794	
>    1795		list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
>    1796			if (!vfio_ap_mdev_has_crycb(matrix_mdev))
>    1797				continue;
>    1798	
>    1799			if (ap_remove) {
>    1800				if (vfio_ap_mdev_unassign_apids(matrix_mdev, apid_rem))
>    1801					unassigned = true;
>    1802				vfio_ap_mdev_unlink_apids(matrix_mdev, apid_rem);
>    1803			}
>    1804	
>    1805			if (aq_remove) {
>    1806				if (vfio_ap_mdev_unassign_apqis(matrix_mdev, apqi_rem))
>    1807					unassigned = true;
>    1808				vfio_ap_mdev_unlink_apqis(matrix_mdev, apqi_rem);
>    1809			}
>    1810		}
>    1811	}
>    1812	
>> 1813	void vfio_ap_mdev_on_cfg_add(void)
>    1814	{
>    1815		unsigned long *cur_apm, *cur_aqm, *prev_apm, *prev_aqm;
>    1816	
>    1817		cur_apm = (unsigned long *)matrix_dev->config_info.apm;
>    1818		cur_aqm = (unsigned long *)matrix_dev->config_info.aqm;
>    1819	
>    1820		prev_apm = (unsigned long *)matrix_dev->config_info_prev.apm;
>    1821		prev_aqm = (unsigned long *)matrix_dev->config_info_prev.aqm;
>    1822	
>    1823		bitmap_andnot(matrix_dev->ap_add, cur_apm, prev_apm, AP_DEVICES);
>    1824		bitmap_andnot(matrix_dev->aq_add, cur_aqm, prev_aqm, AP_DOMAINS);
>    1825	}
>    1826	
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org