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Message-ID: <9fb1c0dd-ea78-a3f7-9eac-3154f5d08ad5@linux.intel.com>
Date:   Wed, 3 May 2023 14:37:16 +0800
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Cc:     baolu.lu@linux.intel.com, Will Deacon <will@kernel.org>,
        David Woodhouse <dwmw2@infradead.org>,
        "Raj, Ashok" <ashok.raj@intel.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        "Yu, Fenghua" <fenghua.yu@intel.com>,
        "Jiang, Dave" <dave.jiang@intel.com>,
        "Luck, Tony" <tony.luck@intel.com>,
        "Zanussi, Tom" <tom.zanussi@intel.com>,
        "Ranganathan, Narayan" <narayan.ranganathan@intel.com>
Subject: Re: [PATCH v5 4/7] iommu/vt-d: Factoring out PASID set up helper
 function
Content-Language: en-US
To:     "Tian, Kevin" <kevin.tian@intel.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>,
        Robin Murphy <robin.murphy@arm.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Joerg Roedel <joro@8bytes.org>,
        "dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>,
        "vkoul@kernel.org" <vkoul@kernel.org>
References: <20230427174937.471668-1-jacob.jun.pan@linux.intel.com>
 <20230427174937.471668-5-jacob.jun.pan@linux.intel.com>
 <BN9PR11MB5276726E67301703BD10833B8C6B9@BN9PR11MB5276.namprd11.prod.outlook.com>
From:   Baolu Lu <baolu.lu@linux.intel.com>
In-Reply-To: <BN9PR11MB5276726E67301703BD10833B8C6B9@BN9PR11MB5276.namprd11.prod.outlook.com>
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On 4/28/23 5:47 PM, Tian, Kevin wrote:
>> From: Jacob Pan <jacob.jun.pan@linux.intel.com>
>> Sent: Friday, April 28, 2023 1:50 AM
>>
>>
>> +static int dmar_domain_attach_device_pasid(struct dmar_domain *domain,
>> +					   struct intel_iommu *iommu,
>> +					   struct device *dev, ioasid_t pasid)
>> +{
>> +	int ret;
>> +
>> +	/* PASID table is mandatory for a PCI device in scalable mode. */
>> +	if (!sm_supported(iommu) && dev_is_real_dma_subdevice(dev))
>> +		return -EOPNOTSUPP;
> 
> "&&" should be "||"
> 

Also should return success instead if this is a RID case. Perhaps,

	if (!sm_supported(iommu) || dev_is_real_dma_subdevice(dev))
		return pasid == RID2PASID ? 0 : -EOPNOTSUPP;

Best regards,
baolu