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Message-ID: <563d4144-f1ad-4603-ba51-667232be3add@linux.intel.com>
Date: Mon, 25 Dec 2023 09:00:08 +0800
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Subject: Re: [RFC PATCH v6 2/4] iommu/vt-d: don's issue devTLB flush request
 when device is disconnected
To: Lukas Wunner <lukas@wunner.de>
Cc: bhelgaas@google.com, baolu.lu@linux.intel.com, dwmw2@infradead.org,
 will@kernel.org, robin.murphy@arm.com, linux-pci@vger.kernel.org,
 iommu@lists.linux.dev, linux-kernel@vger.kernel.org
References: <20231224050657.182022-1-haifeng.zhao@linux.intel.com>
 <20231224050657.182022-3-haifeng.zhao@linux.intel.com>
 <20231224103225.GA31197@wunner.de>
From: Ethan Zhao <haifeng.zhao@linux.intel.com>
In-Reply-To: <20231224103225.GA31197@wunner.de>
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On 12/24/2023 6:32 PM, Lukas Wunner wrote:
> On Sun, Dec 24, 2023 at 12:06:55AM -0500, Ethan Zhao wrote:
>> --- a/drivers/iommu/intel/pasid.c
>> +++ b/drivers/iommu/intel/pasid.c
>> @@ -481,6 +481,9 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu,
>>   	if (!info || !info->ats_enabled)
>>   		return;
>>   
>> +	if (pci_dev_is_disconnected(to_pci_dev(dev)))
>> +		return;
>> +
>>   	sid = info->bus << 8 | info->devfn;
>>   	qdep = info->ats_qdep;
>>   	pfsid = info->pfsid;
> Do you even need this or is patch [4/4] sufficient?
> Is there a benefit to the hunk above on top of patch [4/4]?

Need this,  I don't want to access config space here, check the

flag here is enough, but patch [4/] needs to know if the device

  is gone by reading device vendor info.


Thanks,

Ethan


> Thanks,
>
> Lukas