cuda-gdb and cuobjdump: nvdisasm hangs

Accelerated Computing CUDA CUDA Programming and Performance
1

Hi
I have observed that I cannot used cuda-gdb and/or cuobjdump -sass with some of my cuda programs.
I am using CUDA toolkit V9.2.88

In both cases, the process nvdisasm runs at 100% cpu core utilization and uses up all available memory (32 GB).
(cmdline is “nvdisasm /tmp/sometmpfile -b SM61 -hex”)

For example, a simple program which I cannot use cuobjdump -sass on is the dynamic parallelism example from the other post:

#include <stdio.h>

__global__
void kernel2(int n){
        printf("thread %d in kernel2 called by thread %d from kernel1\n", threadIdx.x, n);
}

__global__
void kernel1(){
        kernel2<<<1,4>>>(threadIdx.x);
}

int main(){
        kernel1<<<1,2>>>();
        cudaDeviceSynchronize();

        cudaDeviceReset();
}

Compiled with nvcc -arch=sm_61 -g -G -rdc=true -o main main.cu

If I run cuobjdump -sass main, I only get the output
Fatbin elf code:

arch = sm_61
code version = [1,7]
producer =
host = linux
compile_size = 64bit
has debug info
compressed
identifier = main.cu

    code for sm_61
            Function : cudaDeviceGetAttribute
    .headerflags    @"EF_CUDA_SM61 EF_CUDA_PTX_SM(EF_CUDA_SM61)"

then the lock up occurs.

Is this a bug? Does someone else observe the same behavior?

In a more complex example, I was able to use objdump after compiling with -G. without it → lock up

2

Based on your description, this does appear to be a bug (maybe a memory leak or infinite recursion). I would suggest filing a bug report with NVIDIA.