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Date:   Thu, 24 Feb 2022 17:39:43 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc:     Christoph Hellwig <hch@lst.de>, iommu@lists.linux-foundation.org,
        x86@kernel.org, Stefano Stabellini <sstabellini@kernel.org>,
        Juergen Gross <jgross@suse.com>,
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Subject: Re: cleanup swiotlb initialization
Message-ID: <20220224163943.GA32088@lst.de>
References: <20220222153514.593231-1-hch@lst.de> <09cb4ad3-88e7-3744-b4b8-a6d745ecea9e@oracle.com> <20220224155854.GA30938@lst.de> <206ba6a3-770a-70ad-96bc-76c6380da988@oracle.com>
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On Thu, Feb 24, 2022 at 11:18:33AM -0500, Boris Ostrovsky wrote:
>
> On 2/24/22 10:58 AM, Christoph Hellwig wrote:
>> Thanks.
>>
>> This looks really strange as early_amd_iommu_init should not interact much
>> with the changes.  I'll see if I can find a AMD system to test on.
>
>
> Just to be clear: this crashes only as dom0. Boots fine as baremetal.

Ah.  I can gues what this might be.  On Xen the hypervisor controls the
IOMMU and we should never end up initializing it in Linux, right?