[Xen-devel] PCI passthrough stopped working, brainache!

[Andy Burns <burns.me.uk@xxxxxxxxx>]

Recently had passthrough of 2xPCI DVB-T cards and 1xPCIe DVB-S2 card working,
the last know config that was *certainly* working was

dom0
xen-4.1.1-3.fc16.x86_64
kernel-3.1.0-0.rc7.git0.0.fc16.x86_64

domU
kernel-3.1.0-0.rc8.git0.0.fc16.x86_64

Since then I've updated

xen-4.1.1-6.fc16.x86_64 on dom0

kernel-3.1.0-0.rc9.git0.0.fc16.x86_64 on dom0 and domU

and updated all other packages to current F16 updates-testing,
also lots of fiddling with grub2 and systemd on the domU

Only today did I realise that only the PCIe card is now working, not
the PCI ones, and have since spent several hours trying to get back to
a working configuration :-(

I've rolled my xen packages back from 4.1.1-6 to 4.1.1-3
tried booting various combinations of 3.1.0-rc7/rc8/rc9 as dom0 and domU

made sure I still have "pci=resource_alignment" for all the relevant
PCI devices on the dom0
made sure I still have "iommu=soft" on the domU
made sure pci-back is happy with "xm pci-list-assignable-devices"
made sure devices really have been assigned with "xm pci-list mythf16"
made sure the devices and drivers show in the domU with "lspci",
"lsusb" and "lsmod"
checked "xm dmesg" on dom0 and "dmesg" on dom0 and domU that drivers
see the hardware and load firmware OK
scandvb goes through the motions of tuning, but finds no stations,
this  *feels* as though the issue is lack of DMA transfers.

How can I tell if the iommu=soft is taking effect?
Anything stupid I sound like I've forgotten?

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel