In your guest lspci log file, I do see the attached SAS device is owned by mpt2sas driver in your guest log.

We did simple testing with a SAS controller assignment to RHEL6.2 guest on Xen unstable 25164, both passthrough and pci-attach/detach works well.

Sharing the log to you, and can you update your Xen to latest and try?


Thanks,
-Xudong

From: xen-devel-bounces@lists.xen.org [mailto:xen-devel-bounces@lists.xen.org] On Behalf Of Aleksandr Tarutin
Sent: Thursday, April 12, 2012 3:52 AM
To: xen-devel@lists.xen.org
Subject: [Xen-devel] PCI Passthrough of SAS controller not working

Hello.

I tried to setup PCI Passthrough of a SAS controller into a PVHVM domU. The device was present in the domU but its modules wouldn't load.

The first related thing was the following message in the guest BIOS just before grub starts:
MPT BIOS Fault 09h encountered at adapter PCI(00h,05h,00h).

I'm attaching the xm dmesg and dmesg from both the host and a guest as well as lspci -v.

--
AT.