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

[Kiszka, Jan]

Build on top of Marcel's -device for IOMMUs patches, add a device property. 
Sorry, no reference at hand.

Jan

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-----Original Message-----
From: Aviv B.D. address@hidden
Received: Samstag, 28 Mai 2016, 18:12
To: Kiszka, Jan (CT RDA ITP SES-DE) address@hidden; Jason Wang address@hidden; 
address@hidden address@hidden
CC: Alex Williamson address@hidden; Peter Xu address@hidden; Michael S. Tsirkin 
address@hidden
Subject: Re: [Qemu-devel] [PATCH v3 1/3] IOMMU: add VTD_CAP_CM to vIOMMU 
capability exposed to guest

What is the best way to add this configuration option?

Aviv.

On Tue, May 24, 2016 at 12:25 PM Jan Kiszka 
<address@hidden<mailto:address@hidden>> wrote:
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<mailto:address@hidden>>
>>
>> This flag tells the guest to invalidate tlb cache also after unmap
>> operations.
>>
>> Signed-off-by: Aviv Ben-David <address@hidden<mailto: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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