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Message-ID: <72ce37d6-69bc-4580-a795-7a6638eae0ee@intel.com>
Date: Tue, 26 Dec 2023 14:15:43 +0800
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Subject: Re: [PATCH v7 7/9] iommu/vt-d: Allow qi_submit_sync() to return the
 QI faults
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To: "Tian, Kevin" <kevin.tian@intel.com>, "joro@8bytes.org" <joro@8bytes.org>,
	"alex.williamson@redhat.com" <alex.williamson@redhat.com>, "jgg@nvidia.com"
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CC: "cohuck@redhat.com" <cohuck@redhat.com>, "eric.auger@redhat.com"
	<eric.auger@redhat.com>, "nicolinc@nvidia.com" <nicolinc@nvidia.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>, "mjrosato@linux.ibm.com"
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 Zhenzhong" <zhenzhong.duan@intel.com>, "joao.m.martins@oracle.com"
	<joao.m.martins@oracle.com>, "Zeng, Xin" <xin.zeng@intel.com>, "Zhao, Yan Y"
	<yan.y.zhao@intel.com>, "j.granados@samsung.com" <j.granados@samsung.com>
References: <20231221153948.119007-1-yi.l.liu@intel.com>
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From: Yi Liu <yi.l.liu@intel.com>
In-Reply-To: <BN9PR11MB527663D97345FC8CD9683AB28C98A@BN9PR11MB5276.namprd11.prod.outlook.com>
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On 2023/12/26 12:13, Tian, Kevin wrote:
>> From: Liu, Yi L <yi.l.liu@intel.com>
>> Sent: Tuesday, December 26, 2023 12:03 PM
>>
>> On 2023/12/22 12:23, Tian, Kevin wrote:
>>>> From: Liu, Yi L <yi.l.liu@intel.com>
>>>> Sent: Thursday, December 21, 2023 11:40 PM
>>>>
>>>> +	fault &= DMA_FSTS_IQE | DMA_FSTS_ITE | DMA_FSTS_ICE;
>>>> +	if (fault) {
>>>> +		if (fsts)
>>>> +			*fsts |= fault;
>>>
>>> do we expect the fault to be accumulated? otherwise it's clearer to
>>> just do direct assignment instead of asking for the caller to clear
>>> the variable before invocation.
>>
>> not quite get. do you mean the fault should not be cleared in the caller
>> side?
>>
> 
> I meant:
> 
> 	if (fsts)
> 		*fsts = fault;
> 
> unless there is a reason to *OR* the original value.

I guess no such a reason. :) let me modify it.

-- 
Regards,
Yi Liu