Bug 189734

Summary: program and system freezes when using springs
Product: [Applications] step Reporter: yentlvt
Component: generalAssignee: Vladimir Kuznetsov <ks.vladimir>
Status: RESOLVED FIXED    
Severity: crash CC: oakad, soulnet
Priority: VHI    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Ubuntu   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description yentlvt 2009-04-15 19:37:20 UTC 
Version:           0.1.0 (using KDE 4.2.2)
OS:                Linux
Installed from:    Ubuntu Packages

Step completely freezes when creating a spring, in every situation. The freeze starts when clicking on the first object (no dragging, clicking the second object or simulation). Other drag objects (like motors) work properly. It was my first time using Step on this install. The complete system stalls and the hard disk led stays on. Only way to exit step is with xkill and a lot of patience, since the system barely responds, even the movement and clicking of the mouse has a major slowdown. Already tried removing and reinstalling it, with no succes. Backtraces give no result. I have used step on another install (Ubuntu 8.10 x86) without any problems, but with Ubuntu 9.04 beta x64 (and on ext4, should it matter) it does no longer work.
Comment 1 David Erosa García 2009-05-12 10:44:34 UTC 
I can confirm this using Ubuntu Jaunty on x86.
Trying to set the first point of a spring makes the app freeze and to use 100% cpu.
With strace:
# strace step
...
(Here I try to use a spring)
...
clock_gettime(CLOCK_MONOTONIC, {8374, 522494049}) = 0
time(NULL)                              = 1242117616
time(NULL)                              = 1242117616
time(NULL)                              = 1242117616
mprotect(0xac732000, 49152, PROT_READ|PROT_WRITE) = 0
mmap2(NULL, 266240, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xad969000
mremap(0xad969000, 266240, 524288, MREMAP_MAYMOVE) = 0xac953000
mremap(0xac953000, 524288, 1052672, MREMAP_MAYMOVE) = 0xac4ff000
mremap(0xac4ff000, 1052672, 2097152, MREMAP_MAYMOVE) = 0xac2ff000
mremap(0xac2ff000, 2097152, 4198400, MREMAP_MAYMOVE) = 0xabefe000
mremap(0xabefe000, 4198400, 8388608, MREMAP_MAYMOVE) = 0xab6fe000
mremap(0xab6fe000, 8388608, 16781312, MREMAP_MAYMOVE) = 0xaa6fd000
mremap(0xaa6fd000, 16781312, 33554432, MREMAP_MAYMOVE) = 0xa86fd000
mremap(0xa86fd000, 33554432, 67112960, MREMAP_MAYMOVE) = 0xa46fc000
^CProcess 7555 detached
derosa@bowman:~/Desktop$

I ctrl+c the process as it starts taking all the memory and CPU.
Comment 2 Vladimir Kuznetsov 2009-05-13 20:30:20 UTC 
It seems that the bug is visible only with Qt 4.5.
Comment 3 Vladimir Kuznetsov 2009-05-13 20:38:30 UTC 
SVN commit 967684 by ksvladimir:

BUG: 189734 Fixed bug in spring rendering code (reproducable only with Qt 4.5).

 M  +1 -1      springgraphics.cc  


WebSVN link: http://websvn.kde.org/?view=rev&revision=967684
Comment 4 Vladimir Kuznetsov 2009-05-13 20:41:48 UTC 
The bugfix is backported to 4.2 and will be available in KDE 4.2.4 (June 3rd).
Comment 5 Vladimir Kuznetsov 2009-05-14 19:54:24 UTC 
*** Bug 192692 has been marked as a duplicate of this bug. ***