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Date:   Tue, 30 May 2023 21:12:55 -0700
From:   Nicolin Chen <nicolinc@nvidia.com>
To:     Baolu Lu <baolu.lu@linux.intel.com>
CC:     Jason Gunthorpe <jgg@ziepe.ca>, Kevin Tian <kevin.tian@intel.com>,
        "Joerg Roedel" <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        "Yi Liu" <yi.l.liu@intel.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        <iommu@lists.linux.dev>, <linux-kselftest@vger.kernel.org>,
        <virtualization@lists.linux-foundation.org>,
        <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCHES 00/17] IOMMUFD: Deliver IO page faults to user space
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On Wed, May 31, 2023 at 10:10:15AM +0800, Baolu Lu wrote:

> I agree with you that the existing IOPF framework is not ideal for
> IOMMUFD. The adding ASYNC flag conflicts with the IOPF workqueue.
> This could lead to performance issues.
> 
> I can improve the IOPF framework to make it more friendly to IOMMUFD.
> One way to do this would be not use workqueue for the IOMMUFD case.
> 
> Have I covered all your concerns?

Yea. My concern was mainly at the fault report for non-PRI cases.
Though I am still on the fence about using IOPF framework, let's
see first how the improved design would look like.

Thanks
Nic