Re: [PATCH v14 0/4] vfio: selftest: Add NVIDIA GPU Falcon DMA test driver

[Alex Williamson <alex@shazbot.org>]

On Tue,  9 Jun 2026 16:28:51 -0700
Rubin Du <rubind@nvidia.com> wrote:

> Patch 1:
> 
> Add a chunking loop to vfio_pci_driver_memcpy() so that it handles
> arbitrarily sized memcpy requests by breaking them into
> max_memcpy_size-sized chunks. This allows tests to request any memcpy
> size. Update the test to use a size of 4x max_memcpy_size to exercise
> the chunking logic.
> 
> Patch 2:
> 
> Add vfio_pci_cmd_set()/vfio_pci_cmd_clear() macros for PCI_COMMAND
> operations.
> 
> Patch 3:
> 
> Allow drivers that cannot trigger MSI interrupts to leave the
> send_msi callback NULL. Tests check ops->send_msi directly and
> gracefully skip MSI-related operations when it is absent.
> 
> Patch 4:
> 
> Introduce the nv_falcon plugin driver, which extracts and adapts
> relevant functionality from NVIDIA's gpu-admin-tools project [1] and
> integrates it into the VFIO selftest framework. As a result, any
> system equipped with a PCIe slot and a supported NVIDIA GPU can now
> run VFIO DMA selftests using commonly available hardware.
> 
> Falcons are general-purpose microcontrollers present on NVIDIA GPUs
> that can perform DMA operations between system memory and device
> memory.
> 
> [1] https://github.com/NVIDIA/gpu-admin-tools
> 
> Changes for v14:
>  - Re-tested with vfio_pci_driver_test on K2200, M60, P100, P4000, V100,
>    T4, RTX 3090, RTX 4000 Ada and H100.
>  - Alex prepared this respin addressing David's review of v13.
>  - Patch 1 & 3: No change.
>  - Patch 2: R-b collected.
>  - Patch 4: address David's review -
>    - Include <linux/types.h>
>    - Factor out get_elapsed_ms()
>    - Rename NV_*_BOOT_COMPLETE_MASK to _SUCCESS
>    - Drop the redundant falcon_enable() and move the no_outside_reset
>      check to the top of falcon_enable() so falcon_reset() is
>      unconditional
>    - Fold dev_err() and size_to_dma_encoding() into nv_falcon_dma()
>    - Drop gpu->memcpy_count and the redundant GPU_ARCH_UNKNOWN assert
>    - Alignment fixes
> 
> Note on version numbering: v1 through v9 were internal review iterations
> that were mistakenly carried over to the upstream submission. Apologies
> for the confusion, the internal changelog has been dropped.
> 
> Rubin Du (4):
>   vfio: selftests: Add memcpy chunking to vfio_pci_driver_memcpy()
>   vfio: selftests: Add generic PCI command register helpers
>   vfio: selftests: Allow drivers without send_msi() support
>   vfio: selftests: Add NVIDIA Falcon driver for DMA testing
> 
>  .../selftests/vfio/lib/drivers/nv_falcon/hw.h | 352 ++++++++
>  .../vfio/lib/drivers/nv_falcon/nv_falcon.c    | 783 ++++++++++++++++++
>  .../lib/include/libvfio/vfio_pci_device.h     |  14 +
>  tools/testing/selftests/vfio/lib/libvfio.mk   |   2 +
>  .../selftests/vfio/lib/vfio_pci_driver.c      |  21 +-
>  .../selftests/vfio/vfio_pci_driver_test.c     |  57 +-
>  6 files changed, 1206 insertions(+), 23 deletions(-)
>  create mode 100644 tools/testing/selftests/vfio/lib/drivers/nv_falcon/hw.h
>  create mode 100644 tools/testing/selftests/vfio/lib/drivers/nv_falcon/nv_falcon.c
> 
> 
> base-commit: d0c3bcd5b8976159d835a897254048e078f447e6
> --
> 2.43.0

Applied to vfio next branch for v7.3.  Thanks,

Alex