Hi,

I need to perform PCI device pass through using Linux KVM virtualization.

Apparently this needs an IOMMU and my 790GX board does not have one.

According to an Anandtech article, as well as other Googles, the 890FX will provice IOMMU support.

Can somebody confirm this?
If it does, will all 890FX boards inherit this functionality from the chipset?

Thanks,

J1M.

Multiple posts will not get you an answer faster and only help to annoy the people you are requesting help from

QB

-------------------------

---

The MONSTER HTPC

---

CPU: AMD Phenom II X4 965 C2 (140W).||.Cooler: Corsair H80i
MB: Gigabyte 990FXA-UD7.||.RAM: 8 GB Mushkin Blackline DDR3 2000MHz (7-10-8-27-1T)
Case: CoolerMaster HAF 932.||.PSU: Corsair HX750
GPU:HIS IceQ 5 Radeon HD 5770 Turbo 1GB.||.Audio: Creative X-Fi Titanium Fatal1ty Pro w/ Logitech Z-5300e (5.1, 280W-RMS)
Drive: 2xKingston SSD 40GB RAID0.||.Storage: 6TB (4x500GB Caviar Black RAID0, 2TB Hitachi & 2TB Caviar Green)

Apologies, I thought I'd posted my first thread in the wrong location so I reposted.

Thanks,

J1M.

Hello,

I am also questioning the support of IOMMU in this chipsetl. I have bought a Gigabyte GA-890FXA-UD5 board and this does NOT have IOMMU support in the BIOS. Further investigation was done, I submitted a ticket to Gigabyte asking if there will be support in the BIOS in the future and I got back a short response "Unfortunately the feature is not supported on this board". Also, on AMD's specs [1] for this chipset don't spec IOMMU. I don't know how updated this site is, but I've read from many many sources that the 890FX chipset has IOMMU. If you are interested, I have started a thread [2] on another forum that might provide some information to you. Many people are posting saying that they too are having the same problem, lack of support in the BIOS. It seems we all want this enabled for KVM or Xen for GNU/Linux.

Cheers,

kuzew

[1] - http://www.amd.com/us/products...md-890fx-chipset.aspx
[2] - http://forums.tweaktown.com/f6...mmu-bios-switch-39801/

Hi,

Thanks for the info, sorry to hear about your board not doing the do.

FWIW I've got this from ASRock:



I've replied asking them if this is because they've not enabled BIOS support for IOMMU.
I shall also go and join your other thread.

Thanks,

J1M.

Please see my questions posted here:
Title: "GPU passthrought support -- difference between GART and IOMMU"
http://forums.amd.com/forum/me...threadid=138483


People are asking the same questions again and again:
Does 890FX support IOMMU? Either it's a GART or an AMD-Vi IOMMU. Of course, more education from AMD on performance differences among no-IOMMU, GART IOMMU, and AMD-Vi IOMMU will help a lot.

Why can't the answer be simple and clear? Just like:
Yes, both GART and AMD-Vi (IOMMU 1.2)
No
Not now, but is slated for MM/YYYY
Not now, no date scheduled yet (not much different from a NO)

**If motherboard manufactures can affect the overall answer due to their BIOS support, then just say so. At least, IOMMU customers can still search for another manufacture's 890FX boards. They don't have to stay in the cloud.

I found this thread [1] interesting. There seems to be an embedded answer from AMD to this question, but it still lacks a source reference(such as an AMD ticket#, AMD article link, or AMD engineer's name) and needs further clarification on GART or AMD-Vi support status. Here is the interesting excerpt:
[
Quote
Thank you for contacting AMD. I would like to verify for you that yes, the 890FX chipset does offer the IOMMU feature, however you will want to keep in mind that manufacturers can decide to enable or disable this feature through the BIOS and therefore you will want to verify with manufacturer of your specific board. But in short, yes it does offer the ability to do so.
]
Interested readers can also find this user jdma's similar post here [2].

Currently, my collected info reflects:
--------------------------------------------
Asus 890FX (i.e., M4A89TD Pro and Crosshair IV) reported IOMMU working [2,3,5,6]
Gigabyte GA-890FXA-UD5 and UD7 with beta version BIOS claiming supporting IOMMU [3,7]
MSI 890FXA-GD70 with beta BIOS 1.75, aka A7640AMS.175 reported IOMMU working [2,3,4]
Asrock 890FX Deluxe3 reported IOMMU working [3,8]
Biostar TA890FXE reported IOMMU working [3]

I have yet to find to what extent each manufacture supports their IOMMU boards and their users' experience. A link on reference 3 to a user's IOMMU experience of GA-890FXA-UD5 is broken.

References:
---------------
[1] http://forum-en.msi.com/index.php?topic=138848
[2] http://forum-en.msi.com/index.php?topic=139125.0
[3] http://wiki.xensource.com/xenwiki/VTdHowTo
[4] http://forum-en.msi.com/index.php?topic=140954
[5] http://vip.asus.com/forum/view...?id=20100609185547531
[6] http://blog.laspina.ca/ubiquit...s-storage-within-esxi
[7] http://forums.tweaktown.com/gi...u-bios-switch-14.html
[8] http://forums.tweaktown.com/as...s-890fx-deluxe3-3.html

Edited: 09/03/2010 at 03:56 AM by cnchang

After reading a wide array of articles on concern about 890FX boards' IOMMU support, I am baffled with how the key IOMMU support info is handled for 890FX chipset and motherboards. Strangely enough, some users, instead of asking vendors to provide key info, simply decided to take matters into their own hands and did some tests themselves without first knowing on what grounds or to what extent their attained beta BIOS or the newly released BIOS can achieve its designated IOMMU functions.

I believe these IOMMU related questions can only be answered with legitimacy and authority when vendors are willing to put matters into perspective. If only to find other users' hands-on reports scattered around, interested users may get scared and hesitated to buy those high end 890FX boards on concern that IOMMU may never get out of beta and never be truly supported. Here are some questions calling for 890FX/IOMMU vendors' attention.

1. Why is IOMMU support not openly listed on the AMD 890FX chipset document [1] as shown in its server chipset counterparts [2]?

2. On what grounds or to what extent will IOMMU be supported on 890FX chipset or its boards at this time?
For example, has 890FX been tested successfully on certain editions/versions of Xen, KVM, or VirtualBox for PCI passthru or GPU passthru?
Another example, have 890FX boards been tested to run IOMMU in a stable manner so that it is not necessary to set Xen IOMMU boot parameters to workaround incorrect ACPI DMAR, DRHD or RMRR tables in the BIOS?

3. Any PCI/VGA passthru performance data from vendors to show the merits of using IOMMU?

I am currently waiting for some vendors' answers. I will update them accordingly. Let me know if you find something that helps answer these questions.

References
--------------
[1] http://www.amd.com/us/products...md-890fx-chipset.aspx
[2] http://www.amd.com/us/products...rm-specifications.aspx

Edited: 09/03/2010 at 11:03 AM by cnchang

Hi moderator,

Is there any place to escalate these spec related questions? I tried to contact AMD support directly thru http://emailcustomercare.amd.com/ . But, I received an email reply, from NoReply@amd.com, like this:

+++++++++++++++++
This is an automatically generated email, please do not reply.

Dear Customer,

You submitted your Service Request from an email address that has not been registered in our Services Portal.

In order to process your inquiry, we require you to submit your query via our services portal.

http://emailcustomercare.amd.com

We apologize for any inconvenience.

Best regards,

AMD Global Customer Care
+++++++++++++++++++++

Not sure how to get registered in AMD's Services Portal. Do you have any way to bring AMD guys' attention on this spec related issue? It seems like they are not reading this forum, or at least not responding to this thread.

Hi cnchang,

Were you able to obtain any further answers to or info with regards to your 3 questions from related vendors? I'm curious to know before I buy an 890FX board.

I have a ASUS Crosshair IV Formula and there is a setting in my BIOS for this feature as shown below:



Not sure if it works or not....or to that end, what it does TBH.

Hope this helps.

What are the benefits of using it? Are there any benefits in enabling it for benchmarks or gaming at all?? Does it help CrossFire setups? I am at a complete loss here but am interested in learning the practical aspects of this feature.

-------------------------
The opinions expressed above do not represent those of Advanced Micro Devices or any of their affiliates.


Edited: 10/01/2010 at 05:52 PM by Canis-X

Hi amdolewy,

The last response I got from AMD Taiwan on 9/13 is that 890FX chipset does not support IOMMU, as it is not stated in the spec. But, it may work as currently supported by some 890FX motherboard manufactures in form of beta or new BIOS. But, officially from AMD Taiwan, the answer is IOMMU not supported by 890FX yet.

I tried to send an email to AMD Global Customer Care (http://emailcustomercare.amd.com/), and I got a response like this:

>>
You submitted your Service Request from an email address that has not been registered in our Services Portal.
<<

Later I got another response like this:
>>
Your service request : SR #{ticketno:[8200347250]} has been reviewed and updated.

Response and Service Request History:

Unfortunately there is no reference testing information on Linux/Open Source operating systems available from AMD Global Customer Care for the Radeon chipset products. This information would come exclusively from the specific motherboard manufacturer if available.

We have drivers online for Linux but they are provided as is with no support or troubleshooting.

If you are running one of the versions referenced as compatible in the Release Notes, Red Hat Enterprise/Novell/SuSE/Ubuntu, you should have access to the feature. If the version you are using will install the drivers the features should also be available but probably not without issues.

All Linux help is self help online.

You may click on the link below and go to its website to find information that might be helpful to your case. Our Engineers are informal contributors.
http://wiki.cchtml.com/index.php/Main_Page\

http://www.hardwareheaven.com/...isplay-drivers/

http://wiki.cchtml.com/index.p...order="0">istributions
http://www.rage3d.com/content/articles/atilinuxhowto/

This is also a very good article from a third party
http://www.rage3d.com/content/...000000000000000


If you are experiencing problems with our latest driver release, or if you have suggestions about how to make our drivers better, please take the time to submit your feedback.
http://www.amdsurveys.com/se.a...A1E27D23CFE9B36

<<

Then, I replied to AMD Global Customer Care:
>>
I don't recall having sent a request for this Radeon chipset Linux support
question.
However, I did sent the following question on 9/8 asking for the AMD 890fx
chipset's IOMMU or AMD-Vi support.
"Why is IOMMU support not openly listed on the AMD 890FX chipset document as
shown in its server chipset counterparts? "
More details about this issue can be found in AMD forum
http://forums.amd.com/forum/me...d=134410&enterthread=y .
I received an email reply saying my email address is not registered in AMD's
Service Portal.

Is this ticketno:[8200347250] regarding the above mentioned issue?
Are you able to provide answers on this "IOMMU support" issue?
<<

This is the last message I got from AMD Global Customer Care on 9/16:
>>
Dear Customer,

Your service request : SR #{ticketno:[8200347250]} has been reviewed and updated.

Response and Service Request History:

The only information available from AMD Global Customer Care is what is available on line, if the information is not online from AMD Global Customer Care cannot confirm/deny/make comment on any detail.

What I can do is direct the feedback to the Catalyst Crew Team, AMD Engineering and the Web Development Team to see if the information can be posted for end user access. This has been done.

You may also want to try accessing the information through the Fusion Partner Program if you qualify as a system builder/reseller.

http://www.amd.com/us/partners...s/partners.aspx


In order to update this service request, please respond, leaving the service request reference intact.
<<