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Date: Mon, 20 May 2024 09:38:42 +0800
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Cc: baolu.lu@linux.intel.com, "iommu@lists.linux.dev"
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Subject: Re: [PATCH v5 5/9] iommufd: Add iommufd fault object
To: "Tian, Kevin" <kevin.tian@intel.com>, Jason Gunthorpe <jgg@ziepe.ca>,
 Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
 Robin Murphy <robin.murphy@arm.com>,
 Jean-Philippe Brucker <jean-philippe@linaro.org>,
 Nicolin Chen <nicolinc@nvidia.com>, "Liu, Yi L" <yi.l.liu@intel.com>,
 Jacob Pan <jacob.jun.pan@linux.intel.com>,
 Joel Granados <j.granados@samsung.com>
References: <20240430145710.68112-1-baolu.lu@linux.intel.com>
 <20240430145710.68112-6-baolu.lu@linux.intel.com>
 <BN9PR11MB52769AC595B6BDA8FB4639258CEC2@BN9PR11MB5276.namprd11.prod.outlook.com>
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From: Baolu Lu <baolu.lu@linux.intel.com>
In-Reply-To: <BN9PR11MB52769AC595B6BDA8FB4639258CEC2@BN9PR11MB5276.namprd11.prod.outlook.com>
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On 5/15/24 4:37 PM, Tian, Kevin wrote:
>> +		iopf_free_group(group);
>> +		done += response_size;
>> +
>> +		iommufd_put_object(fault->ictx, &idev->obj);
> get/put is unpaired:
> 
> 		if (!idev || idev->obj.id != response.dev_id)
> 			idev = iommufd_get_object();
> 
> 		...
> 
> 		iommufd_put_object(idev);
> 
> The intention might be reusing idev if multiple fault responses are
> for a same idev. But idev is always put in each iteration then following
> messages will access the idev w/o holding the reference.

Good catch. Let me fix it by putting the response queue in the fault
object.

Best regards,
baolu