DE Cinnamon
GC AMD 7870HD GHZ edition
OS Arch Linux
kernel  4.0.1-1
mesa-10.5.4-1 & mesa 10.5.5-1 (may effect many others)

Dota2 locks GPU when trying to select a naga siren clone, this happens with either her skill or a manta sytle it hard locks mesa, It should be noted other characters can use manta without the crash. 

Steps to reproduce.
1.) run steam, dota2
2.) start any game with naga siren
3.) cast skill 1 (or buy a mantastyle) and select any or all clone(s)


Some useful bits from a pipe...

Steam: An X Error occurred
X Error of failed request:  BadWindow (invalid Window parameter)
Major opcode of failed request:  40 (X_TranslateCoords)
Resource id in failed request:  0x1212f7b
Serial number of failed request:  7617
xerror_handler: X failed, continuing
Installing breakpad exception handler for appid(dota_linux)/version(1.0)
Looking up breakpad interfaces from steamclient
Calling BreakpadMiniDumpSystemInit
Steam_SetMinidumpSteamID:  Caching Steam ID:  xxx [API loaded yes]
Steam_SetMinidumpSteamID:  Setting Steam ID:  xxx
[0512/103641:ERROR:renderer_main.cc(227)] Running without renderer sandbox
radeon: The kernel rejected CS, see dmesg for more information.
steamwebhelper: Fatal IO error 11 (Resource temporarily unavailable) on X server :0.0.
Fatal IO error 11 (Resource temporarily unavailable) on X server :0.0.
XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":0.0"
      after 5698 requests (5698 known processed) with 671 events remaining.
Assert( Assertion Failed: CFileWriterThread: pending file writer content_log.txt ):/home/buildbot/buildslave/steam_rel_client_linux/build/src/tier1/../tier1/fileio.cpp:4008

I haven't been able to get any errors to log and maybe have to start a ssh server to grab a dmesg log.