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Message-ID: <64fa931b-ea2d-f425-5baa-654216bac779@linux.intel.com>
Date:   Tue, 22 Mar 2022 13:03:14 +0800
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Cc:     baolu.lu@linux.intel.com, "Tian, Kevin" <kevin.tian@intel.com>,
        Joerg Roedel <joro@8bytes.org>,
        Christoph Hellwig <hch@infradead.org>,
        "Raj, Ashok" <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.com>,
        Eric Auger <eric.auger@redhat.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        "Pan, Jacob jun" <jacob.jun.pan@intel.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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To:     Jason Gunthorpe <jgg@nvidia.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>
References: <20220320064030.2936936-1-baolu.lu@linux.intel.com>
 <20220320064030.2936936-11-baolu.lu@linux.intel.com>
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From:   Lu Baolu <baolu.lu@linux.intel.com>
Subject: Re: [PATCH RFC 10/11] iommu: Make IOPF handling framework generic
In-Reply-To: <20220321124346.GP11336@nvidia.com>
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On 2022/3/21 20:43, Jason Gunthorpe wrote:
> On Mon, Mar 21, 2022 at 11:42:16AM +0000, Jean-Philippe Brucker wrote:
> 
>> I tend to disagree with that last part. The fault is caused by a specific
>> device accessing shared page tables. We should keep that device
>> information throughout the fault handling, so that we can report it to the
>> driver when things go wrong.
> SVA faults should never be reported to drivers??
> 

When things go wrong, the corresponding response code will be responded
to the device through iommu_page_response(). The hardware should then
report the failure to the device driver and the device driver will
handle it in the device-specific way. There's no need to propagate the
I/O page faults to the device driver in any case. Do I understand it
right?

Best regards,
baolu