Bug 974662 - virtual machine mouse cursor is off by about 3 pixels with spice
virtual machine mouse cursor is off by about 3 pixels with spice
Product: Fedora
Classification: Fedora
Component: xorg-x11-drv-qxl (Show other bugs)
All Linux
medium Severity medium
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Assigned To: Dave Airlie
Fedora Extras Quality Assurance
: Reopened
Depends On:
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Reported: 2013-06-14 14:28 EDT by Jeff Bastian
Modified: 2013-12-17 14:17 EST (History)
7 users (show)

See Also:
Fixed In Version:
Doc Type: Bug Fix
Doc Text:
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Clone Of:
Last Closed: 2013-12-17 14:17:41 EST
Type: Bug
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oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
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Attachments (Terms of Use)
screenshot of gimp (137.40 KB, image/png)
2013-06-14 14:28 EDT, Jeff Bastian
no flags Details
stars drawn in gimp (19.64 KB, image/png)
2013-06-14 15:04 EDT, Jeff Bastian
no flags Details

  None (edit)
Description Jeff Bastian 2013-06-14 14:28:37 EDT
Created attachment 761400 [details]
screenshot of gimp

Description of problem:
The mouse cursor on Fedora 19 TC3 in a virtual machine is off by about 3 pixels horizontally and 2 pixels vertically.  I.E., if you click on x,y, it registers at x-3,y-2.

In the attached screenshot, I used Gimp to draw a 1 pixel dot and you can see where it was drawn relative to the mouse cursor.

This seems like a minor problem, but I noticed it because the scroll bars in Gnome Shell are rather narrow with the Adwaita theme, so if I click near the left edge of the scroll bar, it doesn't scroll but instead sends the click to the window.  I hit this in Anaconda when trying to scroll through the package groups.  I tried to scroll down the list but instead it selected the Cinnamon Desktop.

This does not happen on Fedora 18 in a virtual machine.

Version-Release number of selected component (if applicable):
Fedora 19 TC3

How reproducible:
every time

Steps to Reproduce:
1. install Fedora 19 TC3 in a virtual machine on a Fedora 19 host
   using Spice graphics and a USB tablet (the defaults)
2. start a gnome-terminal and run "ls /usr/bin"
3. move mouse to left half of gnome-terminal scrollbar and try to click
4. start Gimp and use the Pencil tool to draw a 1 pixel dot

Actual results:
the cursor is an I shape for selecting text and cannot scroll
dot in Gimp is a few pixels away from the mouse cursor

Expected results:
the cursor changes to an arrow and lets you scroll
dot in Gimp is directly under the tip of the arrow cursor

Additional info:
Comment 1 Jeff Bastian 2013-06-14 15:01:15 EDT
I switched my virtual machine settings to VNC with Cirrus graphics and now the cursor is right on spot when drawing a single-pixel-dot in gimp.

Unfortunately there seems to be some graphics corruption, though: the color select is a series of black-and-white lines instead of colors.
Comment 2 Jeff Bastian 2013-06-14 15:04:30 EDT
Created attachment 761407 [details]
stars drawn in gimp

I used Gimp and the Pencil tool to draw a 25-pixel star stencil.  I did it with both Spice/QXL graphics and with VNC/Cirrus graphics for the virtual machine.

I took screenshots showing the star and the mouse cursor, then I scaled the screenshots to double-size and cropped it to just the star and cursor.

You can see the top star -- with Spice -- the cursor is a little down-and-right from the center of the star.  But the bottom star -- with VNC -- the cursor is dead-center in the star.
Comment 3 Jeff Bastian 2013-06-14 15:09:21 EDT
This may be unrelated, but I'm also seeing missing letters in Anaconda when I install with Spice/QXL graphics, but it works ok with VNC.  See bug 974198
Comment 4 Jeff Bastian 2013-06-17 11:07:58 EDT
This appears to be related to recent changes to add KMS support to the qxl driver.

I booted my virtual machine with "nomodeset" and the mouse clicks are where they're supposed to be now, right at the tip of the cursor.
Comment 5 Jeff Bastian 2013-06-17 11:11:34 EDT
Booting with nomodeset also appears to fix bug 974198, the missing text in anaconda)!

I noticed this in my /tmp/X.log (from anaconda environment):

[    14.230] qxl_kms_surface_create: Bad bpp: 1 (1)
[    14.231] qxl_kms_surface_create: Bad bpp: 1 (1)
[    14.231] qxl_kms_surface_create: Bad bpp: 1 (1)

This error comes from a recent commit to the qxl driver:
  qxl: add KMS support v1.2

And this is what gave me the idea to try booting with nomodeset
Comment 6 Dave Airlie 2013-06-19 21:58:42 EDT
I won't get this fixed for F19 GA, but I'm working on having fixes soon after, it needs a few new interfaces to pass information from the user driver to the kernel driver.
Comment 7 Dave Airlie 2013-09-20 06:56:10 EDT
this should be fixed in f19 now, reopen if not.
Comment 8 Jeff Bastian 2013-09-20 11:02:00 EDT
I just built a fresh F19 VM with all the latest updates and I still have the problem.


Comment 9 Cole Robinson 2013-12-17 14:17:41 EST
I verified that this issue still exists with current F19 updates, but there's an update coming that fixes it:


I can't edit the update to track this bug, so I'll just close as CURRENTRELEASE. Please reopen if that package in the guest (and a reboot) doesn't fix the issue.

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