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Date:   Thu, 10 Aug 2023 13:47:09 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     "Tian, Kevin" <kevin.tian@intel.com>
Cc:     Baolu Lu <baolu.lu@linux.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>,
        Nicolin Chen <nicolinc@nvidia.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 08/12] iommu: Prepare for separating SVA and IOPF
Message-ID: <ZNUUjXMrLyU3g5KM@ziepe.ca>
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On Thu, Aug 10, 2023 at 02:35:40AM +0000, Tian, Kevin wrote:
> > From: Baolu Lu <baolu.lu@linux.intel.com>
> > Sent: Wednesday, August 9, 2023 6:41 PM
> > 
> > On 2023/8/9 8:02, Tian, Kevin wrote:
> > >> From: Jason Gunthorpe <jgg@ziepe.ca>
> > >> Sent: Wednesday, August 9, 2023 2:43 AM
> > >>
> > >> On Thu, Aug 03, 2023 at 08:16:47AM +0000, Tian, Kevin wrote:
> > >>
> > >>> Is there plan to introduce further error in the future? otherwise this
> > should
> > >>> be void.
> > >>>
> > >>> btw the work queue is only for sva. If there is no other caller this can be
> > >>> just kept in iommu-sva.c. No need to create a helper.
> > >>
> > >> I think more than just SVA will need a work queue context to process
> > >> their faults.
> > >>
> > >
> > > then this series needs more work. Currently the abstraction doesn't
> > > include workqueue in the common fault reporting layer.
> > 
> > Do you mind elaborate a bit here? workqueue is a basic infrastructure in
> > the fault handling framework, but it lets the consumers choose to use
> > it, or not to.
> > 
> 
> My understanding of Jason's comment was to make the workqueue the
> default path instead of being opted by the consumer.. that is my 1st
> impression but might be wrong...

Yeah, that is one path. Do we have anyone that uses this that doesn't
want the WQ? (actually who even uses this besides SVA?)

Jason