ubuntu-x-swat team mailing list archive

[Thomas Foss <tafoxx@xxxxxxxxx>]

You can say that again...

On Thu, Jun 4, 2009 at 3:17 PM, ichudov <igor@xxxxxxxxxx> wrote:

> When people say "Linux is not ready for desktop", this is what they
> mean.
>
> --
> [i965] X freezes starting on April 3rd
> https://bugs.launchpad.net/bugs/359392
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in X.org xf86-video-intel: Confirmed
> Status in “compiz” source package in Ubuntu: In Progress
> Status in “xserver-xorg-video-intel” source package in Ubuntu: Fix Released
> Status in compiz in Ubuntu Jaunty: Fix Committed
> Status in xserver-xorg-video-intel in Ubuntu Jaunty: Confirmed
> Status in compiz in Ubuntu Karmic: In Progress
> Status in xserver-xorg-video-intel in Ubuntu Karmic: Fix Released
>
> Bug description:
> [Problem]
> Starting around 4/3, when mesa was upgraded from 7.3 to 7.4, several i965
> users started noticing X freeze after several hours of use, triggered by
> application usage especially noticeable with (but not unique to) compiz
> enabled.
>
> [Impact]
> The freeze bug affects a subset of i965 based systems, most particularly
> those using compiz.  Exact numbers cannot be determined, but may be as high
> as 25-50% based on rough estimates.
>
> The problem is severe:  An unpredictable lockup of the system that requires
> a power cycle to recover from.  For some users it comes on within minutes,
> while for others it comes after a few hours of use.
>
> [How Addressed in Development Version]
> For now, the patch being proposed for Jaunty has been uploaded to Karmic.
>
> Longer term, we plan to move from EXA to UXA once the latter is stable
> enough.  It has been found that while UXA exhibits other kinds of freezes,
> we've not yet been able to reproduce this particular freeze there.
>
> [Patch for Jaunty]
> A low-risk workaround that has proven effective at eliminating freezes, or
> at least greatly reducing their frequency, is to increase the Virtual
> framebuffer size.  Some users do this locally as a matter of course to gain
> dual-head support, so this setting has received extremely widespread testing
> already.
>
> The patch for Jaunty causes the Virtual size to be set to 2048x2048 if it
> is not otherwise specified.  Users can still override this with their own
> settings, larger or smaller, as desired.
>
> A side effect of this patch is that it also mitigates bug 158415 to a
> degree, which will make projector usage somewhat easier for this hardware
> because it will enable X to recognize higher resolutions available from the
> external monitor than were available on initial boot.
>
> [Test Case]
> The best method found to reproduce the bug is:
>  a.  Enable compiz
>  b.  Set your desktop to a 6x1 workspace layout
>  c.  Run http://launchpadlibrarian.net/25683477/repro.sh
>  d.  System will freeze anywhere from 1-20 min typically
>  e.  Power-button shutdown is required to reset the system
>
> [Regression Potential]
> In general, Virtual has been widely and extensively tested, so we do not
> expect this patch to trigger regressions.
>
> The patch is coded to only take effect on i965 systems, so the scope of any
> regression that might conceivably be triggered will be limited to just that
> hardware.
>
> [Suspects]
> Omitting obviously trivial, unrelated changes, here are what changed in
> several suspect packages in the timeframe in question:
>
> * intel driver:
>  4/01:  118_drop_legacy3d.patch: Removed Legacy3D
>  4/03:  114_fix_xv_with_non_gem.patch: Dropped since it caused regression
>  4/06:  119_drm_bo_unreference_needs_null.patch: Fixes various nullptr
> derefs
>  4/08:  120_fix_vt_switch.patch: Fix nullptr deref in video playback
>
> * xserver:
>  4/08:  177_animated_cursor_change_master.patch: fixes animated cursors
>  4/06:  174_set_bg_pixmap_of_cow_to_none.patch: Sets bg pixmap of
>         composite overlay window to None
>  3/30:  172_cwgetbackingpicture_nullptr_check.patch: fix race condition
>         when minimzing/maximizing firefox with flash video playing.
>
> * mesa:
>  4/03:  7.4 released
>    * Added MESA_GLX_FORCE_DIRECT env var for Xlib/software driver
>    * GLSL version 1.20 is returnd by the GL_SHADING_LANGUAGE_VERSION query
>    * glGetActiveUniform() returned wrong size for some array types
>    * Fixed some error checking in glUniform()
>    * Fixed a potential glTexImage('proxy target') segfault
>    * Fixed bad reference counting for 1D/2D texture arrays
>    * Fixed VBO + glPush/PopClientAttrib() bug #19835
>   * Assorted i965 driver bug fixes
>    * Fixed a Windows compilation failure in s_triangle.c
>    * Fixed a GLSL array indexing bug
>    * Fixes for building on Haiku
>
> * linux:
>  4/04:  2.6.28-11.41:  Revert MCHBAR patch
>  4/02:  2.6.28-11.40:  Add MCHBAR patch
>
> * libdrm:
>  4/04:  02_libdrm_nouveau_update.patch: Only affects nouveau code
>  3/29:  libdrm-nouveau1.symbols: Probably innocuous
>
> [Workarounds]
> Various people have found one or more of the following have helped to
> reduce the frequency or eliminate the freezes:
>
>  * Turn off compiz
>  * AccelMethod UXA
>  * Set NoAccel true
>  * Set Virtual to something high
>  * MigrationHeuristic greedy
>  * Revert to 2.4 -intel driver
>
> [Current Theory]
> A 3D memory buffer accumulates data until something gets in there
> incorrectly and leads to a freeze.  This can happen either slowly over a
> long period of light use, or fairly soon if using the system heavily.  It is
> not simply a matter of filling the memory up, so the trigger often seems to
> be random, but usually follows some sort of graphics transition (such as the
> 3D effect from alt-tab, or closing a firefox window).
>
> It is fairly certain that there are multiple freeze bugs present in X.org
> with the -intel driver.  This causes significant confusion when people
> having different bugs think they might have the same one, and find the
> symptoms and workarounds don't match.  It is also suspected that the same
> root bug may have multiple different ways of triggering it.
>
> Increasing the Virtual settings seems to either eliminate or greatly reduce
> the frequency of these freezes.  Presumably this allocates larger memory
> buffers so the chances of something hitting a wrong thing are greatly
> lessened.  However, none of this is well understood.
>
> [Original Report]
> I am using kubuntu jaunty beta. My system is freezing randomly. I have the
> latest updates.
> After freezing the mouse pointer still works. And sometimes the power off
> button works. On powering off , when the stage for kubuntu logo comes its
> showing a distorted image.
>
> This happens with or without desktop effects. These freezes are very
> randomly, but mostly when I run some new applications.
> I am using intel graphics.
>
> [lspci]
> 00:00.0 Host bridge [0600]: Intel Corporation Mobile PM965/GM965/GL960
> Memory Controller Hub [8086:2a00] (rev 0c)
>        Subsystem: Hewlett-Packard Company Device [103c:30be]
> 00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile
> GM965/GL960 Integrated Graphics Controller [8086:2a02] (rev 0c)
>        Subsystem: Hewlett-Packard Company Device [103c:30be]
>
>

-- 
[i965] X freezes starting on April 3rd
https://bugs.launchpad.net/bugs/359392
You received this bug notification because you are a member of Ubuntu-X,
which is the registrant for xf86-video-intel.