"Unspecified Launch Failure" Error CUDA and GLSL issues

Hi, All —

I’m getting the following error back from CUDA at run time in a program that uses both CUDA and GLSL to first process and then render particle system data.

[font=“Courier”]“Cuda error in file ‘cudakernel.cu’ - line 214 - Unspecified Launch Failure”[/font]

cudakernel.cu is the module that does the setup and execution of the kernel, but does not contain the kernel proper. Line 214 is the second CUDA_SAFE_CALL() instance below:

[font=“Courier”]extern “C” void
RunCUDA(float Time)
{
float *posPtr;
float dms;

...{code here}...

// map OpenGL buffer object for writing from CUDA
CUDA_SAFE_CALL(cudaGLMapBufferObject( (void**)&posPtr, cuda_vboPos));

// execute the kernel
dim3 block(CUDA_BLOCK_SIZE, 1, 1);
dim3 grid(numParticles / block.x, 1, 1);
kernel<<< grid, block >>>((float4 *)posPtr, (float4 *)dev_velData, (const float4 *)dev_rndData, Time );

// unmap buffer object
CUDA_SAFE_CALL(cudaGLUnmapBufferObject( cuda_vboPos ));        // <=== UNSPECIFIED LAUNCH FAILURE error on this line

}[/font]

The curious thing is, the error only occurs when I change the value of a #DEFINE constant in the kernel itself from 0.00001 to 0.00001f. I can post the kernel if anyone wants to see it, but it’s a might lengthy.

I am reasonably sure that the error does not happen without the ‘f’, and even with it it only happens about once every minute (~50 frames at 60 fps), after which point the program crashes and Windows freaks out - little flakes of “fuzz” appear all over any redrawn windows and only a reboot fixes it. After raising the error, sometimes the system BSODs with the following code:

[font=“Courier”]The computer has rebooted from a bugcheck. The bugcheck was: 0x100000ea (0x89c8a7a8, 0x8a025d58, 0xba4fbcbc, 0x00000001).
[/font]
BSOD code 0x100000ea is associated with THREAD_STUCK_IN_DEVICE_DRIVER_M, which basically means the GPU is in an infinite loop (according to this Microsoft KB article)

I’ve tried two different systems, both with 8600’s and CUDA 1.1…no luck

Any advice?

Thanks!

Ben