Linux support for AMD 890FX ?

[tashlan]

I am looking to build a new server/desktop for virtualization experimentation/learning. Specifically, I'm interested in testing IOMMU support on RHEL6 using KVM.

I'm looking at G34, C32, and AM3 boards. I think I'd like to base my build on the Asus Formula IV board (AM3) as it gives me a PCIe slot for IOMMU testing, costs less, and fits a standard case.

Seems most view this board as a Windows gaming/overclock board. Even among the circles where this chipset is recognized for IOMMU support, little is mentioned about overall Linux support or performance. Note: many 890FX boards do not have IOMMU support in the BIOS. All the Asus boards do, however.

Can anyone comment on Linux support for this chipset, or better, support for the Formula IV.

I'm looking to use RHEL6 (CentOS) so Fedora 12/13 would be suitably close to what I'm planning. BTW- sounds like a great review article.

[jrch2k8]

I am looking to build a new server/desktop for virtualization experimentation/learning. Specifically, I'm interested in testing IOMMU support on RHEL6 using KVM.

I'm looking at G34, C32, and AM3 boards. I think I'd like to base my build on the Asus Formula IV board (AM3) as it gives me a PCIe slot for IOMMU testing, costs less, and fits a standard case.

Seems most view this board as a Windows gaming/overclock board. Even among the circles where this chipset is recognized for IOMMU support, little is mentioned about overall Linux support or performance. Note: many 890FX boards do not have IOMMU support in the BIOS. All the Asus boards do, however.

Can anyone comment on Linux support for this chipset, or better, support for the Formula IV.

I'm looking to use RHEL6 (CentOS) so Fedora 12/13 would be suitably close to what I'm planning. BTW- sounds like a great review article.

well i havent tested myself iommu since my mobo is an 880g but about the chipset is already fully supported on linux.

checking on google i dont think redhat 6 will support iommu since it seems the patches went through in kernel 2.6.34 or some of the imporntant ones at least(not entirely sure)

on the AMD virtualizacion on the cpu is also supported up to the latest bits in the six core phenom of my home again kernel 2.6.34 in case(ubuntu base kernel sux)

from what i readed it seems that any kernel greater than 2.6.34 will support iommu just fine but im not 100% sure about it, at least on my opteron server have been fine using iommu with the 2.6.34 kernel so far

[tashlan]

Thanks for the answer and additional information.

Looks like they are back-porting IOMMU support into a few minor versions back from 2.6.34, so I imagine I won't have to wait too long before it is included without compiling my own kernel.

I know this isn't a mature technology yet, I was trying to get in early and play around with the technology. We will be using this more at work in the future and I need to get my hands dirty.

I was mostly worried about the NIC not working or the platform being unstable. I'm planning on using this as my desktop also and need to be able to use this thing while the code catches up!

One note, I did find that video cards are not currently supported by IOMMU. That's a shame, I was hoping to virtualize my desktop OS with direct access to the video card from the guest.

[tashlan]

Follow-up...

Stopped back in to confirm support for the 890FX chipset. My Asus Crossfire iv Formula (C4F) is up and running only minor issues.

With Fedora 12 the ethernet did not work out-of-the-box, but did work after upgrading the kernel to 2.6.32.16-150. Now running on Fedora 13 with zero compatibility issues. Sound was detected and working in both with no extra setup needed.

IOMMU support for this board is confirmed present in the current BIOS (0905).

NOTE: the 890FX Northbridge runs pretty hot (20w dissipation), make sure your board has adequate cooling. Some early C4F boards had issues with this.