Re: [PATCH] iommu/arm-smmu: Defer probe of clients after smmu device bound

[kernel test robot]

Hi Pratyush,

kernel test robot noticed the following build warnings:

[auto build test WARNING on soc/for-next]
[also build test WARNING on linus/master v6.12-rc1 next-20241001]
[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/Pratyush-Brahma/iommu-arm-smmu-Defer-probe-of-clients-after-smmu-device-bound/20241001-135852
base:   https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git for-next
patch link:    https://lore.kernel.org/r/20241001055633.21062-1-quic_pbrahma%40quicinc.com
patch subject: [PATCH] iommu/arm-smmu: Defer probe of clients after smmu device bound
config: i386-buildonly-randconfig-004-20241002 (https://download.01.org/0day-ci/archive/20241002/202410020820.gY0d4AkK-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/20241002/202410020820.gY0d4AkK-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/202410020820.gY0d4AkK-lkp@xxxxxxxxx/

All warnings (new ones prefixed by >>):

   drivers/iommu/arm/arm-smmu/arm-smmu.c: In function 'arm_smmu_probe_device':
>> drivers/iommu/arm/arm-smmu/arm-smmu.c:1441:32: warning: returning 'int' from a function with return type 'struct iommu_device *' makes pointer from integer without a cast [-Wint-conversion]
    1441 |                         return dev_err_probe(dev, -EPROBE_DEFER, "smmu dev has not bound yet\n");
         |                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


vim +1441 drivers/iommu/arm/arm-smmu/arm-smmu.c

  1419	
  1420	static struct iommu_device *arm_smmu_probe_device(struct device *dev)
  1421	{
  1422		struct arm_smmu_device *smmu = NULL;
  1423		struct arm_smmu_master_cfg *cfg;
  1424		struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
  1425		int i, ret;
  1426	
  1427		if (using_legacy_binding) {
  1428			ret = arm_smmu_register_legacy_master(dev, &smmu);
  1429	
  1430			/*
  1431			 * If dev->iommu_fwspec is initally NULL, arm_smmu_register_legacy_master()
  1432			 * will allocate/initialise a new one. Thus we need to update fwspec for
  1433			 * later use.
  1434			 */
  1435			fwspec = dev_iommu_fwspec_get(dev);
  1436			if (ret)
  1437				goto out_free;
  1438		} else {
  1439			smmu = arm_smmu_get_by_fwnode(fwspec->iommu_fwnode);
  1440			if (!smmu)
> 1441				return dev_err_probe(dev, -EPROBE_DEFER, "smmu dev has not bound yet\n");
  1442		}
  1443	
  1444		ret = -EINVAL;
  1445		for (i = 0; i < fwspec->num_ids; i++) {
  1446			u16 sid = FIELD_GET(ARM_SMMU_SMR_ID, fwspec->ids[i]);
  1447			u16 mask = FIELD_GET(ARM_SMMU_SMR_MASK, fwspec->ids[i]);
  1448	
  1449			if (sid & ~smmu->streamid_mask) {
  1450				dev_err(dev, "stream ID 0x%x out of range for SMMU (0x%x)\n",
  1451					sid, smmu->streamid_mask);
  1452				goto out_free;
  1453			}
  1454			if (mask & ~smmu->smr_mask_mask) {
  1455				dev_err(dev, "SMR mask 0x%x out of range for SMMU (0x%x)\n",
  1456					mask, smmu->smr_mask_mask);
  1457				goto out_free;
  1458			}
  1459		}
  1460	
  1461		ret = -ENOMEM;
  1462		cfg = kzalloc(offsetof(struct arm_smmu_master_cfg, smendx[i]),
  1463			      GFP_KERNEL);
  1464		if (!cfg)
  1465			goto out_free;
  1466	
  1467		cfg->smmu = smmu;
  1468		dev_iommu_priv_set(dev, cfg);
  1469		while (i--)
  1470			cfg->smendx[i] = INVALID_SMENDX;
  1471	
  1472		ret = arm_smmu_rpm_get(smmu);
  1473		if (ret < 0)
  1474			goto out_cfg_free;
  1475	
  1476		ret = arm_smmu_master_alloc_smes(dev);
  1477		arm_smmu_rpm_put(smmu);
  1478	
  1479		if (ret)
  1480			goto out_cfg_free;
  1481	
  1482		device_link_add(dev, smmu->dev,
  1483				DL_FLAG_PM_RUNTIME | DL_FLAG_AUTOREMOVE_SUPPLIER);
  1484	
  1485		return &smmu->iommu;
  1486	
  1487	out_cfg_free:
  1488		kfree(cfg);
  1489	out_free:
  1490		iommu_fwspec_free(dev);
  1491		return ERR_PTR(ret);
  1492	}
  1493	

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