Re: [PATCH 2/3] vmd: disable MSI remapping bypass under Xen

[kernel test robot <lkp@xxxxxxxxx>]

Hi Roger,

kernel test robot noticed the following build errors:

[auto build test ERROR on pci/next]
[also build test ERROR on pci/for-linus tip/irq/core linus/master v6.13-rc6 
next-20250110]
[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/Roger-Pau-Monne/xen-pci-do-not-register-devices-outside-of-PCI-segment-scope/20250110-220331
base:   https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next
patch link:    
https://lore.kernel.org/r/20250110140152.27624-3-roger.pau%40citrix.com
patch subject: [PATCH 2/3] vmd: disable MSI remapping bypass under Xen
config: x86_64-buildonly-randconfig-001-20250112 
(https://download.01.org/0day-ci/archive/20250112/202501121029.dJk0TBPr-lkp@xxxxxxxxx/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): 
(https://download.01.org/0day-ci/archive/20250112/202501121029.dJk0TBPr-lkp@xxxxxxxxx/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@xxxxxxxxx>
| Closes: 
https://lore.kernel.org/oe-kbuild-all/202501121029.dJk0TBPr-lkp@xxxxxxxxx/

All errors (new ones prefixed by >>):

   drivers/pci/controller/vmd.c: In function 'vmd_probe':
>> drivers/pci/controller/vmd.c:973:13: error: implicit declaration of function 
>> 'xen_domain' [-Werror=implicit-function-declaration]
     973 |         if (xen_domain())
         |             ^~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/xen_domain +973 drivers/pci/controller/vmd.c

   966  
   967  static int vmd_probe(struct pci_dev *dev, const struct pci_device_id 
*id)
   968  {
   969          unsigned long features = (unsigned long) id->driver_data;
   970          struct vmd_dev *vmd;
   971          int err;
   972  
 > 973          if (xen_domain())
   974                  /*
   975                   * Xen doesn't have knowledge about devices in the VMD 
bus.
   976                   * Bypass of MSI remapping won't work in that case as 
direct
   977                   * write to the MSI entries won't result in functional
   978                   * interrupts.
   979                   */
   980                  features &= ~VMD_FEAT_CAN_BYPASS_MSI_REMAP;
   981  
   982          if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20))
   983                  return -ENOMEM;
   984  
   985          vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL);
   986          if (!vmd)
   987                  return -ENOMEM;
   988  
   989          vmd->dev = dev;
   990          vmd->instance = ida_alloc(&vmd_instance_ida, GFP_KERNEL);
   991          if (vmd->instance < 0)
   992                  return vmd->instance;
   993  
   994          vmd->name = devm_kasprintf(&dev->dev, GFP_KERNEL, "vmd%d",
   995                                     vmd->instance);
   996          if (!vmd->name) {
   997                  err = -ENOMEM;
   998                  goto out_release_instance;
   999          }
  1000  
  1001          err = pcim_enable_device(dev);
  1002          if (err < 0)
  1003                  goto out_release_instance;
  1004  
  1005          vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0);
  1006          if (!vmd->cfgbar) {
  1007                  err = -ENOMEM;
  1008                  goto out_release_instance;
  1009          }
  1010  
  1011          pci_set_master(dev);
  1012          if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) &&
  1013              dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32))) {
  1014                  err = -ENODEV;
  1015                  goto out_release_instance;
  1016          }
  1017  
  1018          if (features & VMD_FEAT_OFFSET_FIRST_VECTOR)
  1019                  vmd->first_vec = 1;
  1020  
  1021          spin_lock_init(&vmd->cfg_lock);
  1022          pci_set_drvdata(dev, vmd);
  1023          err = vmd_enable_domain(vmd, features);
  1024          if (err)
  1025                  goto out_release_instance;
  1026  
  1027          dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n",
  1028                   vmd->sysdata.domain);
  1029          return 0;
  1030  
  1031   out_release_instance:
  1032          ida_free(&vmd_instance_ida, vmd->instance);
  1033          return err;
  1034  }
  1035  

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