Description of problem: The PVFB graphics driver includes a paravirt mouse input device. When talking to the host OS over xenbus, it advertises that it supports absolute coordinate mode. RHEL-5 userspace is incapable of actually running the mouse in absolute mode by default though, so out of the box the guest OS is doing abs -> rel coordinate conversion. This in turn causes problems for anyone connecting to the guest OS using the VNC server in the host OS because their mouse pointer will likely hit an invisible wall. The absolute mouse coordinate feature should be disabled by default in RHEL-5 guest kernels. A boot parameter, or other tunable should be provided to allow absolute mode to be re-enabled if the admin has manually configured an xorg.conf that supports it. Version-Release number of selected component (if applicable): kernel-xen-2.6.18-128.el5 How reproducible: Always Steps to Reproduce: 1. Boot RHEL-5 guest 2. On host run xenstore-ls /local/domain/0/backend/vkbd 3. Actual results: feature-abs-pointer = "1" Expected results: feature-abs-pointer = "0" Additional info:
Xenstore node /local/domain/0/backend/vkbd shows whether the backend (host) offered the feature. To see whether the frontend (guest) accepted it, which is what you want here, you run # xenstore-read /local/domain/$DOMID/device/vkbd/0/request-abs-pointer
Created attachment 339538 [details] Change PVFB not to select abs. pointer by default This patch makes the xenkbd driver reject absolute pointers, unless they are enabled with kernel parameter xenkbd.abs_pointer=1.
in kernel-2.6.18-141.el5 You can download this test kernel from http://people.redhat.com/dzickus/el5 Please do NOT transition this bugzilla state to VERIFIED until our QE team has sent specific instructions indicating when to do so. However feel free to provide a comment indicating that this fix has been verified.
The original change was at the request of the TAM. I've knocked it down to high/high since the fix is at the ON_QA state.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2009-1243.html