setSVMPointers returns CL_INVALID_VALUE but OpenCL kernel still works correctly

[ClaudiuBalogh]

Using setSVMPointers with plain system memory returns CL_INVALID_VALUE, but the OpenCL kernel still correctly processed data.

The OpenCL kernel worked correctly even when the call to setSVMPointers was completely removed!

Is calling setSVMPointers required for the OpenCL for CPUs runtime when passing pointers to system buffers allocated by new or malloc?

The CPU is an Intel(R) Xeon(R) Gold 5415+

clinfo:

  Platform Name:                                 Intel(R) OpenCL
Number of devices:                               1
  Device Type:                                   CL_DEVICE_TYPE_CPU
  Vendor ID:                                     8086h
  Max compute units:                             32
  Max work items dimensions:                     3
    Max work items[0]:                           8192
    Max work items[1]:                           8192
    Max work items[2]:                           8192
  Max work group size:                           8192
  Preferred vector width char:                   1
  Preferred vector width short:                  1
  Preferred vector width int:                    1
  Preferred vector width long:                   1
  Preferred vector width float:                  1
  Preferred vector width double:                 1
  Native vector width char:                      64
  Native vector width short:                     32
  Native vector width int:                       16
  Native vector width long:                      8
  Native vector width float:                     16
  Native vector width double:                    8
  Max clock frequency:                           0Mhz
  Address bits:                                  64
  Max memory allocation:                         67323510784
  Image support:                                 Yes
  Max number of images read arguments:           480
  Max number of images write arguments:          480
  Max image 2D width:                            16384
  Max image 2D height:                           16384
  Max image 3D width:                            2048
  Max image 3D height:                           2048
  Max image 3D depth:                            2048
  Max samplers within kernel:                    480
  Max size of kernel argument:                   3840
  Alignment (bits) of base address:              1024
  Minimum alignment (bytes) for any datatype:    128
  Single precision floating point capability
    Denorms:                                     Yes
    Quiet NaNs:                                  Yes
    Round to nearest even:                       Yes
    Round to zero:                               No
    Round to +ve and infinity:                   No
    IEEE754-2008 fused multiply-add:             No
  Cache type:                                    Read/Write
  Cache line size:                               64
  Cache size:                                    2097152
  Global memory size:                            134647021568
  Constant buffer size:                          131072
  Max number of constant args:                   480
  Local memory type:                             Global
  Local memory size:                             262144
  Max pipe arguments:                            16
  Max pipe active reservations:                  8191
  Max pipe packet size:                          1024
  Max global variable size:                      65536
  Max global variable preferred total size:      65536
  Max read/write image args:                     480
  Max on device events:                          4294967295
  Queue on device max size:                      4294967295
  Max on device queues:                          4294967295
  Queue on device preferred size:                4294967295
  SVM capabilities:
    Coarse grain buffer:                         Yes
    Fine grain buffer:                           Yes
    Fine grain system:                           Yes
    Atomics:                                     Yes
  Preferred platform atomic alignment:           64
  Preferred global atomic alignment:             64
  Preferred local atomic alignment:              0
  Kernel Preferred work group size multiple:     128
  Error correction support:                      0
  Unified memory for Host and Device:            1
  Profiling timer resolution:                    1
  Device endianess:                              Little
  Available:                                     Yes
  Compiler available:                            Yes
  Execution capabilities:
    Execute OpenCL kernels:                      Yes
    Execute native function:                     Yes
  Queue on Host properties:
    Out-of-Order:                                Yes
    Profiling :                                  Yes
  Queue on Device properties:
    Out-of-Order:                                Yes
    Profiling :                                  Yes
  Platform ID:                                   0xba9300
  Name:                                          Intel(R) Xeon(R) Gold 5415+
  Vendor:                                        Intel(R) Corporation
  Device OpenCL C version:                       OpenCL C 3.0
  Driver version:                                2025.19.4.0.18_160000.xmain-hotfix
  Profile:                                       FULL_PROFILE
  Version:                                       OpenCL 3.0 (Build 0)
  Extensions:                                    cl_khr_spirv_linkonce_odr cl_khr_fp64 cl_khr_fp16 cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_ext_float_atomics cl_khr_3d_image_writes cl_khr_byte_addressable_store cl_khr_depth_images cl_khr_extended_bit_ops cl_khr_icd cl_khr_il_program cl_khr_suggested_local_work_size cl_intel_unified_shared_memory cl_intel_devicelib_assert cl_khr_subgroup_ballot cl_khr_subgroup_shuffle cl_khr_subgroup_shuffle_relative cl_khr_subgroup_extended_types cl_khr_subgroup_non_uniform_arithmetic cl_khr_subgroup_non_uniform_vote cl_khr_subgroup_clustered_reduce cl_intel_subgroups cl_intel_subgroups_char cl_intel_subgroups_short cl_intel_subgroups_long cl_intel_required_subgroup_size cl_intel_spirv_subgroups cl_khr_int64_base_atomics cl_khr_int64_extended_atomics cl_intel_device_attribute_query cl_intel_exec_by_local_thread cl_intel_vec_len_hint cl_intel_device_partition_by_names cl_khr_spir cl_khr_image2d_from_buffer cl_intel_concurrent_dispatch cl_khr_device_uuid cl_khr_integer_dot_product