On oneapi-construction-kit/refsi we support USM but not Host Allocs. The workaround for odd sizes of pattern_size calls clHostMemAllocINTEL_fn which refsi does not support, and likely many implementations won't. refsi does support device allocations however.
This can be reproduced by building cloning https://github.com/codeplaysoftware/oneapi-construction-kit.git and building with:
cmake -GNinja -DCA_MUX_TARGETS_TO_ENABLE="riscv" -DCA_RISCV_ENABLED=ON -DCA_ENABLE_API=cl -DCA_LLVM_INSTALL_DIR=<llvm_install> -DCA_CL_ENABLE_ICD_LOADER=ON -DOCL_EXTENSION_cl_khr_command_buffer=ON -DOCL_EXTENSION_cl_khr_command_buffer_mutable_dispatch=ON
LLVM Install requires RISCV and lld to be enabled.
This is shown up in the SYCL CTS test:
test_queue/queue shortcuts unified shared memory core
where it looks to cover a fill of pattern_size 12 after commit intel/llvm#13788