I believe it is required to send an error event. It checked for the
STATUS TRB and found that it was missing, therefore it must send an
Error Event.
This is (not so clearly) stated in the specification and I have quoted
this in a previous comment.
I took it as:
If the controller checks for the
Well, no. Status TB not being present is an error. The host adapter is
not required to check for that error condition though. If the host
adapter checks for that error condition it should queue an transfer
error. So, yes, we could improve qemu a bit here, by throwing an error
instead of
Just a little more information.
In section 4.11.2.2, page 159 of version 1.0 of the xHCI specification,
it states:
• The xHC shall NOT check for the following Control transfer error conditions.
• If a Data Stage TD follows a Setup Stage TD, where wLength = ‘0’.
• If a Status Stage TD does
Removing this check will indeed require a bit of a re-write. The way
the code is now, the transfer expects a SETUP packet to be first. If
you remove the check I ask about above, will the next transfer show that
it is the STATUS packet? If so, then the check at line 1696 will indeed
catch and
