Created attachment 120709 [details]
strace output

Hi,

I am using the radeon r600 driver on an integrated AMD GPU listed by lspci as
[AMD/ATI] Wrestler [Radeon HD 7340].
It is the GPU part of the AMD E2-2000 APU.

I am on an up-to-date x86-64 Arch Linux [testing] system:

***
mesa 11.1.0
xf86-video-ati 7.6.1
xorg-server 1.18.0
libdrm 2.4.65
llvm 3.7.0
linux 4.3.3
(corresponding 32 bit versions are installed where applicable)
***

While trying to play the Steam game "Gods Will Be Watching", I encounter a hang at the start of chapter 1 with no progress being made at the black screen showing "One Year Ago". This happens whenever I try to load the saved game at that point. Enabling LIBGL_ALWAYS_SOFTWARE allows the game to progress (but at an extremely low frame rate, of course). It does not matter whether I am using DRI2 or DRI3.

Attached is the strace output with me killing the process at the end. I currently do not have debug versions of the libraries installed, so the gdb backtrace is pretty useless, and I am not sure if I captured the right moment:
***
#0  0xf7fd9be5 in __kernel_vsyscall ()
#1  0xf77eda2b in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib32/libpthread.so.0
#2  0xf78f6d8d in pthread_cond_wait@@GLIBC_2.3.2 () from /usr/lib32/libc.so.6
#3  0xe0a10592 in ?? () from /usr/lib32/xorg/modules/dri/r600_dri.so
#4  0xe0a115b0 in ?? () from /usr/lib32/xorg/modules/dri/r600_dri.so
#5  0xe094a317 in ?? () from /usr/lib32/xorg/modules/dri/r600_dri.so
#6  0xe0a2eb69 in ?? () from /usr/lib32/xorg/modules/dri/r600_dri.so
#7  0xe05bce81 in ?? () from /usr/lib32/xorg/modules/dri/r600_dri.so
#8  0xe060709b in ?? () from /usr/lib32/xorg/modules/dri/r600_dri.so
#9  0xe06d9f18 in ?? () from /usr/lib32/xorg/modules/dri/r600_dri.so
#10 0xf7d9ac25 in ?? () from /usr/lib32/libGL.so.1
#11 0xf7d9b00a in ?? () from /usr/lib32/libGL.so.1
#12 0xf7d711a3 in glXSwapBuffers () from /usr/lib32/libGL.so.1
#13 0x08260e61 in ?? ()
#14 0xf7818497 in __libc_start_main () from /usr/lib32/libc.so.6
#15 0x08050c75 in ?? ()
***

Excerpt from glxinfo:
***
Extended renderer info (GLX_MESA_query_renderer):
    Vendor: X.Org (0x1002)
    Device: AMD PALM (DRM 2.43.0, LLVM 3.7.0) (0x9808)
    Version: 11.1.0
    Accelerated: yes
    Video memory: 384MB
    Unified memory: no
    Preferred profile: core (0x1)
    Max core profile version: 3.3
    Max compat profile version: 3.0
    Max GLES1 profile version: 1.1
    Max GLES[23] profile version: 3.0
***

Thank you for your work on the open source Linux graphics stack. It is very much appreciated.

Andreas Kempf