Re: [PATCH v1 3/3] s390/pci: Fence FMB enable/disable via sysfs for passthrough devices

[kernel test robot <lkp@intel.com>]

Hi Omar,

kernel test robot noticed the following build warnings:

[auto build test WARNING on s390/features]
[also build test WARNING on awilliam-vfio/next awilliam-vfio/for-linus kvms390/next linus/master v6.16-rc1 next-20260430]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Omar-Elghoul/s390-pci-Preserve-FMB-state-in-device-re-enablement/20260502-155729
base:   https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git features
patch link:    https://lore.kernel.org/r/20260501192530.9429-4-oelghoul%40linux.ibm.com
patch subject: [PATCH v1 3/3] s390/pci: Fence FMB enable/disable via sysfs for passthrough devices
config: s390-allnoconfig-bpf (https://download.01.org/0day-ci/archive/20260503/202605030313.sqrb6Bdr-lkp@intel.com/config)
compiler: s390x-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260503/202605030313.sqrb6Bdr-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605030313.sqrb6Bdr-lkp@intel.com/

All warnings (new ones prefixed by >>):

   arch/s390/pci/pci.c: In function 'zpci_fmb_enable_device':
>> arch/s390/pci/pci.c:191:23: warning: unused variable 'flags' [-Wunused-variable]
     191 |         unsigned long flags;
         |                       ^~~~~
>> arch/s390/pci/pci.c:189:33: warning: unused variable 'ctrs' [-Wunused-variable]
     189 |         struct zpci_iommu_ctrs *ctrs;
         |                                 ^~~~
   arch/s390/pci/pci.c: In function 'zpci_fmb_reenable_device':
   arch/s390/pci/pci.c:244:23: warning: unused variable 'flags' [-Wunused-variable]
     244 |         unsigned long flags;
         |                       ^~~~~
   arch/s390/pci/pci.c:242:33: warning: unused variable 'ctrs' [-Wunused-variable]
     242 |         struct zpci_iommu_ctrs *ctrs;
         |                                 ^~~~


vim +/flags +191 arch/s390/pci/pci.c

029a3d529699a0 Omar Elghoul    2026-05-01  184  
d0b0885316ab7a Jan Glauber     2012-12-11  185  /* Modify PCI: Set PCI function measurement parameters */
d0b0885316ab7a Jan Glauber     2012-12-11  186  int zpci_fmb_enable_device(struct zpci_dev *zdev)
d0b0885316ab7a Jan Glauber     2012-12-11  187  {
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  188  	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);
92bce97f0c341d Niklas Schnelle 2023-10-04 @189  	struct zpci_iommu_ctrs *ctrs;
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  190  	struct zpci_fib fib = {0};
ecda483339a515 Matthew Rosato  2024-09-10 @191  	unsigned long flags;
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  192  	u8 cc, status;
d0b0885316ab7a Jan Glauber     2012-12-11  193  
0b7589ecca2b6f Sebastian Ott   2016-06-15  194  	if (zdev->fmb || sizeof(*zdev->fmb) < zdev->fmb_length)
d0b0885316ab7a Jan Glauber     2012-12-11  195  		return -EINVAL;
d0b0885316ab7a Jan Glauber     2012-12-11  196  
08b421245692f3 Wei Yongjun     2013-02-25  197  	zdev->fmb = kmem_cache_zalloc(zdev_fmb_cache, GFP_KERNEL);
d0b0885316ab7a Jan Glauber     2012-12-11  198  	if (!zdev->fmb)
d0b0885316ab7a Jan Glauber     2012-12-11  199  		return -ENOMEM;
d0b0885316ab7a Jan Glauber     2012-12-11  200  	WARN_ON((u64) zdev->fmb & 0xf);
d0b0885316ab7a Jan Glauber     2012-12-11  201  
029a3d529699a0 Omar Elghoul    2026-05-01  202  	zpci_fmb_clear_iommu_ctrs(zdev);
6001018ae8c659 Sebastian Ott   2015-04-10  203  
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  204  	fib.fmb_addr = virt_to_phys(zdev->fmb);
c68468ed3416ea Matthew Rosato  2022-06-06  205  	fib.gd = zdev->gisa;
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  206  	cc = zpci_mod_fc(req, &fib, &status);
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  207  	if (cc) {
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  208  		kmem_cache_free(zdev_fmb_cache, zdev->fmb);
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  209  		zdev->fmb = NULL;
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  210  	}
4e5bd7803bd1e8 Sebastian Ott   2017-06-10  211  	return cc ? -EIO : 0;
d0b0885316ab7a Jan Glauber     2012-12-11  212  }
d0b0885316ab7a Jan Glauber     2012-12-11  213  

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki