I have a proven working code running fine on Tesla K20 with cuda-6.5 toolkit. When i try to run this code on Tesla K80 with cuda-8.0, it throws up error ‘Illegal memory access at xx line no in file source.cu’.
To isolate the problem, I tried on Tesla K20 with Cuda-8.0, it worked fine. That means no issues with the toolkit.
I further went on with debugging. the memory allocation with cudaMalloc was fine and copying the data to device through cudaMemCopy was fine. when i call cudaOccupancyMaxPotentialBlockSize to calculate the block and grid sizes, the application is terminating with the error given above. I commented out this line and hard coded the block size and grid size with block size = 1024 and grid size = 42. when i try to launch the kernel again same error is thrown
Thanks in advance.