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From:   "Tian, Kevin" <kevin.tian@intel.com>
To:     Lu Baolu <baolu.lu@linux.intel.com>,
        Joerg Roedel <joro@8bytes.org>, Steve Wahl <steve.wahl@hpe.com>
CC:     David Woodhouse <dwmw2@infradead.org>,
        Jerry Snitselaar <jsnitsel@redhat.com>,
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        "Anderson, Russ" <russ.anderson@hpe.com>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>,
        "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
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Subject: RE: [PATCH v1 4/6] iommu/vt-d: Add VTD_FLAG_IOMMU_PROBED flag
Thread-Topic: [PATCH v1 4/6] iommu/vt-d: Add VTD_FLAG_IOMMU_PROBED flag
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Date:   Thu, 30 Jun 2022 08:29:24 +0000
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> From: Lu Baolu <baolu.lu@linux.intel.com>
> Sent: Saturday, June 25, 2022 8:52 PM
>=20
> In the IOMMU hot-add path, there's a need to check whether an IOMMU
> has been probed. Instead of checking the IOMMU pointer in the global
> list, it's better to allocate a flag bit in iommu->flags for this
> purpose.

Sorry I didn't get the point of original check. This is the hotplug path
hence the caller of this function should already figure out it's a new
iommu before reaching this point?