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Subject: =?UTF-8?Q?Re=3a_A_problem_of_Intel_IOMMU_hardware_=ef=bc=9f?=
To:     Alex Williamson <alex.williamson@redhat.com>
References: <670baaf8-4ff8-4e84-4be3-030b95ab5a5e@huawei.com>
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 <20210317091820.5f4ab69e@omen.home.shazbot.org>
From:   Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <87a5f90a-d1ea-fe7a-2577-fdfdf25f8fd7@linux.intel.com>
Date:   Thu, 18 Mar 2021 10:58:30 +0800
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Hi Alex,

On 3/17/21 11:18 PM, Alex Williamson wrote:
>>>           {MAP,   0x0, 0xc0000000}, --------------------------------- (b)
>>>                   use GDB to pause at here, and then DMA read IOVA=0,
>> IOVA 0 seems to be a special one. Have you verified with other addresses
>> than IOVA 0?
> It is???  That would be a problem.
> 

No problem from hardware point of view as far as I can see. Just
thought about software might handle it specially.

Best regards,
baolu