Date: Mon, 14 Dec 2015 16:08:05 +0100
From: Joerg Roedel <joro@8bytes.org>
To: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org
Subject: Re: [PATCH] iommu/amd: Assign default IOMMU when there is only one
 IOMMU
Message-ID: <20151214150805.GE11292@8bytes.org>
References: <1449874478-31770-1-git-send-email-Suravee.Suthikulpanit@amd.com>
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On Fri, Dec 11, 2015 at 04:54:38PM -0600, Suravee Suthikulpanit wrote:
> Current driver makes assumption that device with devid zero is always
> included in the range of devices to be managed by IOMMU. However,
> certain FW does not include devid zero in IVRS table.
> This has caused IOMMU perf driver to fail to initialize.

Hmm, this is a firmware bug. Is this bug seen in any systems that are
for sale?

> This patch implements a workaround for this case by always assign
> devid zero to be handled by the first IOMMU.

Otherwise its better to fix the firmware than to add workarounds.


	Joerg

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