Installing Xen PV disk didn't cause BSOD but caused other interesting issue, how do I "nicely" remove it?

[tonsimple]

Qubes OS version (e.g., R3.2):

3.2

Affected TemplateVMs (e.g., fedora-23, if applicable):

Windows HVM, Windows templated AppVM

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Expected behavior:

I didn't have any expectations, decided to see what would PV disk driver do.

Actual behavior:

While promised BSOD never happened, about an hour in I noticed that an infrequent "freeze" I occasionally got (and described here #2690) now happens very frequently (about twice an hour)

Steps to reproduce the behavior:

Have a windows VM that occasionally freezes with 100% CPU load (on boot or otherwise)
Install Xen Disk PV drivers
Have 100% CPU freezes much more often, right during work

qga log features lines like
connect_to_daemon: connect to server failed with error 2:
QvUnregisterWatchedDC: ExtEscape(QVESC_STOP_WATCHING_SURFACE) failed, error 0

(but GUI works)

There's also a lot of
TerminateTargetProcess: OpenEvent failed with error 2: Can not find file
QGAWatchdog's log

Is there a way to "gracefully" uninstall the PV disk drivers or should I just revert to backup?

General notes:

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Related issues:

Somehow related to
#2690
(PV disk stuff somehow made it manifest way more frequently)