Bug 181736

Summary: connecting to vnc module with X radeon server freezes box
Product: [Fedora] Fedora Reporter: Alexandre Oliva <oliva>
Component: xorg-x11-drv-atiAssignee: X/OpenGL Maintenance List <xgl-maint>
Status: CLOSED CURRENTRELEASE QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: mcepl, xgl-maint
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: vnc-4.1.2-18.fc7 kernel-2.6.22.1-33.fc7 xorg-x11-server-Xorg-1.3.0.0-9.fc7 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2007-08-01 18:36:23 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Attachments:
Description Flags
panic when the box freezes none

Description Alexandre Oliva 2006-02-16 04:23:05 UTC
Description of problem:
See below

Version-Release number of selected component (if applicable):
xorg-x11-server-Xorg-1.0.1-6.1
xorg-x11-drv-ati-6.5.7.3-3.2
vnc-server-4.1.1-35.1

How reproducible:
Every time

Steps to Reproduce:
1.Set up the X server for a box with an ATI 9200SE card (radeon module) as a vnc
server (Load "vnc")
2.Start the X server
3.Connect to it with vncviewer

Actual results:
After vncviewer opens the window in which the remote screen would be displayed,
it starts painting the window with black, but the box freezes hard part-way
through the process.  Not even SysRq works.

Expected results:
It works fine on other boxes with nv as the primary driver, as well as on this
very box using the vesa driver.

Additional info:
I'm yet to try whether disabling DRI would be of any help.

Comment 1 Alexandre Oliva 2006-02-16 10:26:51 UTC
Same error using the "ati" driver, that today's test release configured for me.

Comment 2 Alexandre Oliva 2006-05-27 09:17:52 UTC
This still applies to current rawhide.

I found out that, if I switch to VT1 before connecting, then the box won't
freeze, but VNC won't work either: the VNC client will repaint only part of the
screen before X freezes, and then, most of the times, even after restarting X,
some consistent screen corruption ensues.

X doesn't actually hang in this case, it just keeps repeating the following
lines over and over:

(EE) RADEON(0): RADEONWaitForIdleCP: CP idle -22
(EE) RADEON(0): Idle timed out, resetting engine...
(**) RADEON(0): EngineRestore (32/32)
(EE) RADEON(0): RADEONWaitForIdleCP: CP reset -22
(EE) RADEON(0): RADEONWaitForIdleCP: CP start -22


Comment 3 Alexandre Oliva 2006-06-17 18:05:24 UTC
This is still present in rawhide :-(  It appears to only occur on SMP systems;
with maxcpus=1, the problem did not occur.  Moving the `Load "vnc"' before other
modules enabled vnc to not freeze immediately, but it still froze in similar
ways to those described in 194043, just faster.  Commenting out Load "dri" and
Load "glx" didn't make any visible difference.

Comment 4 Alexandre Oliva 2006-07-27 04:24:04 UTC
With the following combination (rawhide-20060726):

kernel-xen-2.6.17-1.2449.fc6
xorg-x11-server-Xorg-1.1.1-8.fc6
xorg-x11-drv-ati-6.6.1-5.fc6
vnc-server-4.1.2-3.fc6

vnc just worked.  Yay!, I thought.  No such luck with the non-xen kernel,
though.  That was because DRI/drm could not be brought up properly in the xen
kernel.  I tried both XAA and EXA AccelMethods, to no avail.  Option "NoAccel"
"on" worked around it, but no other option documented in the man page did, not
even Option "RenderAccel" "off", which I was hoping might fix it.  Another
alternative that now works is to comment out Load "dri".

This is most definitely not a vnc problem.  It might be a problem in the
radeon/dri drivers in X, or in the kernel drm side.  Hard to tell.

Comment 5 Alexandre Oliva 2006-07-28 20:48:30 UTC
Removing the Load "dri" was not enough to get around the entire problem,
unfortunately.  The box still froze after some light use of vnc :-(

Comment 6 Alexandre Oliva 2006-08-05 16:26:16 UTC
Created attachment 133692 [details]
panic when the box freezes

Armed with a serial console, I managed to capture what the kernel printed
before freezing.  It talks about an MCE log, but unfortunately there's no time
to run mcelog before the logged data is history :-(

Comment 7 Matěj Cepl 2007-06-25 13:23:20 UTC
Since this bugzilla report was filed, there have been several major updates,
which may have resolved this issue. Users who have experienced this problem are
encouraged to upgrade their system to the latest version of their distribution
available.

Please, if you experience this problem on the up-to-date system, let us now in
the comment for this bug, or whether the upgraded system works for you.

Comment 8 Matěj Cepl 2007-08-01 18:11:37 UTC
Reporter, could you please confirm as that the bug is still reproducable? If you
won't reply in one month, I will have to close this bug as INSUFFICIENT_DATA.
Thank you.

Comment 9 Alexandre Oliva 2007-08-01 18:36:23 UTC
It *seems* like this is fixed in F7, but I haven't used vnc lately as often or
as heavily as I used to, so I can't quite tell.  It surely doesn't freeze right
away any more.  Thanks,