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Date:   Fri, 26 Aug 2022 11:54:44 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Lu Baolu <baolu.lu@linux.intel.com>
Cc:     Joerg Roedel <joro@8bytes.org>,
        Christoph Hellwig <hch@infradead.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Kevin Tian <kevin.tian@intel.com>,
        Ashok Raj <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.com>,
        Dave Jiang <dave.jiang@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Vinod Koul <vkoul@kernel.org>,
        Eric Auger <eric.auger@redhat.com>,
        Liu Yi L <yi.l.liu@intel.com>,
        Jacob jun Pan <jacob.jun.pan@intel.com>,
        Zhangfei Gao <zhangfei.gao@linaro.org>,
        Zhu Tony <tony.zhu@intel.com>, iommu@lists.linux.dev,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v12 09/17] iommu/vt-d: Add blocking domain support
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References: <20220826121141.50743-1-baolu.lu@linux.intel.com>
 <20220826121141.50743-10-baolu.lu@linux.intel.com>
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On Fri, Aug 26, 2022 at 08:11:33PM +0800, Lu Baolu wrote:
> The Intel IOMMU hardwares support blocking DMA transactions by clearing
> the translation table entries. This implements a real blocking domain to
> avoid using an empty UNMANAGED domain. The detach_dev callback of the
> domain ops is not used in any path. Remove it to avoid dead code as well.
> 
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> Tested-by: Tony Zhu <tony.zhu@intel.com>
> ---
>  drivers/iommu/intel/iommu.c | 25 ++++++++++++++++++-------
>  1 file changed, 18 insertions(+), 7 deletions(-)

At this point I'd suggest to make a little series that does all the
blocking domain stuff in one shot

The removal of detach_dev callbacks is pretty nice for clarity.

Jason