Hanging app in shim_glBindFramebuffer() from libMali.so

With the help of a customer, I've narrowed down the cause to shadow mapping.

When I render the light view to a z-texture, and then use this texture to render the camera view in the standard framebuffer, the app will hang.

If I skip the render to texture, there is no crash.

I create the depth texture using:

        // create the framebuffer

        glGenFramebuffers( 1, &shadowFramebuffer );

        glBindFramebuffer( GL_FRAMEBUFFER, shadowFramebuffer );

        // create the texture

        glGenTextures( 1, &shdw_texture );

        glBindTexture( GL_TEXTURE_2D, shdw_texture );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,  GL_CLAMP_TO_EDGE );

        glTexImage2D( GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, SHADOWBUFFERSIZE, SHADOWBUFFERSIZE, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, 0 );

        glFramebufferTexture2D( GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, shdw_texture, 0 );

        GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER) ;

The status returned is GL_FRAMEBUFFER_COMPLETE.

And the ES2 config I use is 8/8/8/24 bits.

The shadowbuffer has size 512x512 texels.

To repro on an affected device:

Go to Google Play store, and search for 'Little Crane'.

Install the free game 'The Little Crane That Could'

Launch any level from the main menu.

After 5s, Application Not Responding occurs, with main thread waiting in shim_glBindFramebuffer()

non Mali devices run fine.

Lastly: note that there is no color attachment attached to the frame buffer.

Normally this is fine, but maybe Mali cannot render to texture without a colour channel?

  Bram

With the help of a customer, I've narrowed down the cause to shadow mapping.

When I render the light view to a z-texture, and then use this texture to render the camera view in the standard framebuffer, the app will hang.

If I skip the render to texture, there is no crash.

I create the depth texture using:

        // create the framebuffer

        glGenFramebuffers( 1, &shadowFramebuffer );

        glBindFramebuffer( GL_FRAMEBUFFER, shadowFramebuffer );

        // create the texture

        glGenTextures( 1, &shdw_texture );

        glBindTexture( GL_TEXTURE_2D, shdw_texture );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );

        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,  GL_CLAMP_TO_EDGE );

        glTexImage2D( GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, SHADOWBUFFERSIZE, SHADOWBUFFERSIZE, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, 0 );

        glFramebufferTexture2D( GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, shdw_texture, 0 );

        GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER) ;

The status returned is GL_FRAMEBUFFER_COMPLETE.

And the ES2 config I use is 8/8/8/24 bits.

The shadowbuffer has size 512x512 texels.

To repro on an affected device:

Go to Google Play store, and search for 'Little Crane'.

Install the free game 'The Little Crane That Could'

Launch any level from the main menu.

After 5s, Application Not Responding occurs, with main thread waiting in shim_glBindFramebuffer()

non Mali devices run fine.

Lastly: note that there is no color attachment attached to the frame buffer.

Normally this is fine, but maybe Mali cannot render to texture without a colour channel?

  Bram