Hi Arm/SMMU experts,
Scenario :- I am trying to assign a device (eg mmc) to a guest which
uses smmu. I start the guest using "xl create -c ...". It works fine for
the first time. I am able to access the device.
Now, when I destroy the guest and create again, I see this issue
(XEN) smmu: /axi/smmu@fd800000: GFSR 0x00000002, GFSYNR0
0x00000000, GFSYNR1 0x00000871, GFSYNR2 0x00000000
0x871 is the stream id used by mmc.
We are using SMMU-500. So from the Arm SMMU v2 specs, it is
"Unidentified stream fault" for stream id "0x871".
This issue is seen regardless we use 'mmu-masters' or 'iommus' property
in xen device tree.
I can confirm that this issue was not seen in xen-4.14.3. It is seen in
our (Xilinx's) latest release ie xen-4.16.1.
I am using our downstream fork of Xen. I can't readily use the upstream
as we use lot of EEMI codebase.
Can someone try to see if this issue exists in the latest upstream Xen ?
Any pointers on how to debug this further ?
Kind regards,
Ayan
