[Spice-devel] Tripping assertions in spice-common/common/ring.h

[Yonit Halperin]

Hi,

Thanks for the detailed description. I've reproduced and found the bug. 
Just sent the patch. You are welcomed to try it :)

Cheers,
Yonit.
On 07/23/2012 03:49 PM, Nahum Shalman wrote:
> On 07/22/2012 02:14 PM, Yonit Halperin wrote:
>> Hi,
>> the trace implies some problem in the drawables tree structure. Please
>> describe in more details how you reproduce it: which web site, which
>> browser you use, what operations you execute on the web site? In
>> addition, what is the qxl driver version, and are surfaces and/or
>> caching enabled?
>> What is the spice-server version? Is it a modified version?
>
> So far I've trimmed the crash process down to:
> 1. Boot the Fedora 16 VM
> 2. Log in, icewm is the window manager.
> 3. Launch google-chrome
> 4. Open pandora.com and get some music playing (serves as a non-visual
> cue that the VM has crashed, doesn't need to be visible on-screen)
> 5. Open another tab and go to http://arbesman.net (make sure that the
> cross-fading images are on-screen and are cross-fading correctly
> (sometimes needs a refresh of the web page))
> 6. In a little while the VM will crash enough that the music stops and
> the UI becomes unresponsive (but QEMU hasn't crashed)
>
> The spice-server is the master branch from the spice git repositories
> (as of ~July 17, I think) with two patches applied:
> One is the ENOPROTOOPT patch that I just sent to the mailing list
> The second is the alteration of the spice_assert macro to invoke
> spice_backtrace on errors (which enabled me to trace the crash).
>
> The QEMU server has some modifications including that it is listening on
> a UNIX socket and a different process is listening on a TCP socket and
> passing the connection through (thus the need for the ENOPROTOOPT
> patch). None of the modifications touch the qxl device code.
>
> I'm not sure of the qxl driver version, we may have made a small
> modification to it to alter which screen resolutions it would run, but
> it's probably relatively old.
> The offscreen surfaces are disabled (they were giving us a performance
> regression with GTK applications like firefox), but the image and
> fallback caches are enabled.
> Here's some of the output it placed in Xorg.0.log:
> [ 8.183] (II) LoadModule: "qxl"
> [ 8.183] (II) Loading /usr/lib64/xorg/modules/drivers/qxl_drv.so
> [ 8.185] (II) Module qxl: vendor="X.Org Foundation"
> [ 8.185] (II) qxl: Driver for QXL virtual graphics: QXL 1
> [ 8.201] (II) Loading /usr/lib64/xorg/modules/drivers/qxl_drv.so
> [ 8.201] (**) qxl(0): Depth 24, (--) framebuffer bpp 32
> [ 8.201] (==) qxl(0): RGB weight 888
> [ 8.201] (==) qxl(0): Default visual is TrueColor
> [ 8.201] (==) qxl(0): Using gamma correction (1.0, 1.0, 1.0)
> [ 8.201] (II) qxl(0): Offscreen Surfaces: Disabled
> [ 8.201] (II) qxl(0): Image Cache: Enabled
> [ 8.201] (II) qxl(0): Fallback Cache: Enabled
> [ 8.209] (II) qxl(0): framebuffer at 0x7f67dfcb1000 (16384 KB)
> [ 8.209] (II) qxl(0): command ram at 0x7f67e0cb1000 (32760 KB)
> [ 8.209] (II) qxl(0): vram at 0x7f67dbcb1000 (65536 KB)
> [ 8.209] (II) qxl(0): rom at 0x7f67e4bc9000
> [ 8.210] (II) qxl(0): Device version 0.0
> [ 8.210] (II) qxl(0): Compression level 0, log level 0
> [ 8.210] (II) qxl(0): 12286 io pages at 0x7f67dfcb1000
> [ 8.210] (II) qxl(0): RAM header offset: 0x3ffe000
> [ 8.210] (II) qxl(0): Correct RAM signature 41525851
> [ 8.210] (II) qxl(0): 49144 KB of video RAM
> [ 8.210] (II) qxl(0): 1024 surfaces
> [ 8.210] (II) qxl(0): <default monitor>: Using hsync range of
> 29.00-160.00 kHz
> [ 8.210] (II) qxl(0): <default monitor>: Using vrefresh range of
> 50.00-75.00 Hz
> [ 8.210] (II) qxl(0): Clock range: 10.00 to 400.00 MHz
> <snip>
> [ 8.219] (II) qxl(0): PreInit complete
> [ 8.219] (II) qxl(0): git commit 5fc9ef5
> [ 8.225] (II) qxl(0): framebuffer at 0x7f67dfcb1000 (16384 KB)
> [ 8.225] (II) qxl(0): command ram at 0x7f67e0cb1000 (32760 KB)
> [ 8.225] (II) qxl(0): vram at 0x7f67dbcb1000 (65536 KB)
> [ 8.225] (II) qxl(0): rom at 0x7f67e4bc9000
>
> Let me know if you need additional details or have variations of my test
> you'd like me to try.
>
> Thanks so much,
> Nahum
>