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Date:   Thu, 23 Jun 2022 13:33:18 +0200
From:   Joerg Roedel <joro@8bytes.org>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     will@kernel.org, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org, hch@lst.de, john.garry@huawei.com
Subject: Re: [PATCH v2] iommu/dma: Add config for PCI SAC address trick
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On Wed, Jun 22, 2022 at 02:12:39PM +0100, Robin Murphy wrote:
> Thanks for your bravery!

It already starts, with that patch I am getting:

	xhci_hcd 0000:02:00.0: AMD-Vi: Event logged [IO_PAGE_FAULT domain=0x000f address=0xff00ffffffefe000 flags=0x0000]

In my kernel log. The device is an AMD XHCI controller and seems to
funciton normally after boot. The message disappears with
iommu.forcedac=0.

Need to look more into that...