Bug 1003620

Summary: RFE: Improve default xen blktap handling (requires libvirt changes)
Product: [Community] Virtualization Tools Reporter: Cole Robinson <crobinso>
Component: virt-managerAssignee: Cole Robinson <crobinso>
Status: CLOSED UPSTREAM QA Contact:
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Version: unspecifiedCC: berrange, crobinso, gscrivan, rbalakri
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Last Closed: 2015-09-23 21:36:07 UTC Type: Bug
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Description Cole Robinson 2013-09-02 13:38:21 UTC
See: https://bugzilla.redhat.com/show_bug.cgi?id=1003610

Libvirt should expose xen blktap support in capabilities XML so virt-manager can stop looking at /proc/modules.

Also, a xen user reported that with recent xen, driver_name=tap2 works but driver_name=tap doesn't:

http://www.redhat.com/archives/virt-tools-list/2013-June/msg00031.html

Might be worth investigating as well

Comment 1 Cole Robinson 2015-09-23 21:36:07 UTC
Just dropped explicit blktap support entirely since it's deprecated upstream:

commit 7c10d8a27f0f635c185d1b85d6d26120d51c8aa2
Author: Cole Robinson <crobinso>
Date:   Wed Sep 23 17:26:48 2015 -0400

    devicedisk: Tweak driver defaults for xen
    
    Following some discussion here:
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1171550
    
    jfehlig suggested better defaults for modern xen. End result is:
    
    - Drop the blktap check, since it's deprecated (yaay)
    - If xen + block device, use driver_name=phy
    - Otherwise if on modern enough libvirt + libxl, do the same thing we
      do for qemu.