gpu: Raise warning in case of CUDA runtime / driver incompat

devito/arch/archinfo.py

@@ -13,6 +13,7 @@
 from devito.tools import all_equal, memoized_func
 
 __all__ = ['platform_registry', 'get_cpu_info', 'get_gpu_info', 'get_nvidia_cc',
+           'check_cuda_runtime',
            'Platform', 'Cpu64', 'Intel64', 'Amd', 'Arm', 'Power', 'Device',
            'NvidiaDevice', 'AmdDevice',
            'INTEL64', 'SNB', 'IVB', 'HSW', 'BDW', 'SKX', 'KNL', 'KNL7210',  # Intel
@@ -344,6 +345,33 @@ def get_nvidia_cc():
         return 10*cc_major.value + cc_minor.value
 
 
+@memoized_func
+def check_cuda_runtime():
+    libnames = ('libcudart.so', 'libcudart.dylib', 'cudart.dll')
+    for libname in libnames:
+        try:
+            cuda = ctypes.CDLL(libname)
+        except OSError:
+            continue
+        else:
+            break
+    else:
+        warning("Unable to check compatibility of NVidia driver and runtime")
+
+    driver_version = ctypes.c_int()
+    runtime_version = ctypes.c_int()
+
+    if cuda.cudaDriverGetVersion(ctypes.byref(driver_version)) == 0 and \
+       cuda.cudaRuntimeGetVersion(ctypes.byref(runtime_version)) == 0:
+        driver_version = driver_version.value
+        runtime_version = runtime_version.value
+        if driver_version < runtime_version:
+            warning("The NVidia driver (v%d) on this system may not be compatible "
+                    "with the CUDA runtime (v%d)" % (driver_version, runtime_version))
+    else:
+        warning("Unable to check compatibility of NVidia driver and runtime")
+
+
 @memoized_func
 def lscpu():
     try:

devito/arch/compiler.py

@@ -12,7 +12,8 @@
 from codepy.jit import compile_from_string
 from codepy.toolchain import GCCToolchain
 
-from devito.arch import AMDGPUX, NVIDIAX, SKX, POWER8, POWER9, get_nvidia_cc
+from devito.arch import (AMDGPUX, NVIDIAX, SKX, POWER8, POWER9, get_nvidia_cc,
+                         check_cuda_runtime)
 from devito.exceptions import CompilationError
 from devito.logger import debug, warning, error
 from devito.parameters import configuration
@@ -494,6 +495,12 @@ def __init__(self, *args, **kwargs):
 
         self.src_ext = 'cu'
 
+        # NOTE: not sure where we should place this. It definitely needs
+        # to be executed once to warn the user in case there's a CUDA/driver
+        # mismatch that would cause the program to run, but likely producing
+        # garbage, since the CUDA kernel behaviour would be undefined
+        check_cuda_runtime()
+
     def __lookup_cmds__(self):
         self.CC = 'nvcc'
         self.CXX = 'nvcc'