Created attachment 132579 [details]
ddebug_mono_500ms_hang.log

The gpu hang can be reproduced very quickly when using R600_DEBUG=mono.

If it helps here is output using GALLIUM_DDEBUG="pipelined 500" R600_DEBUG=mono
apitrace replay -v:

...
20265 glCompileShader(shader = 2041)
20266 glCreateProgram() = 2049
20267 glCreateProgram() = 2050
20268 glCreateProgram() = 2051
...
21287 glCreateProgram() = 3070
21288 glCreateProgram() = 3071
21289 glCreateProgram() = 3072
21290 glAttachShader(program = 3072, shader = 1023)
21291 glAttachShader(program = 3072, shader = 2041)
...
21455 glCreateShader(type = GL_COMPUTE_SHADER) = 3073
21456 glCreateShader(type = GL_COMPUTE_SHADER) = 3074
...
22476 glCreateShader(type = GL_COMPUTE_SHADER) = 4094
22477 glCreateShader(type = GL_COMPUTE_SHADER) = 4095
22478 glCreateShader(type = GL_COMPUTE_SHADER) = 4096

22479 @4 glShaderSource(shader = 4096,
 some shader code
22507 @4 glShaderSource(shader = 4095,
 some shader code (really a lot)
22508 @4 glCompileShader(shader = 4095)
22509 @4 glAttachShader(program = 3070, shader = 4095)
22510 @4 glLinkProgram(program = 3070)
GPU hang detected.
dd: Aborting the process...