Re: [Qemu-devel] [PATCH v3 1/3] IOMMU: add VTD_CAP_CM to vIOMMU capability exposed to guest

[Jan Kiszka]

On 2016-05-24 10:14, Jason Wang wrote:
> On 2016年05月22日 00:19, Aviv B.D wrote:
>> From: "Aviv Ben-David" <address@hidden>
>>
>> This flag tells the guest to invalidate tlb cache also after unmap
>> operations.
>>
>> Signed-off-by: Aviv Ben-David <address@hidden>
>> ---
> 
> Is this a guest visible behavior?  If yes, shouldn't we cache
> translation fault conditions in IOTLB?

It is guest visible, and this first of all means, besides requiring to
be optional, that it definitely needs to be off for compat systems. Or
it stays off by default.

Jan

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