Re: [PATCH v3 0/7] vfio: Improve error reporting when MMIO region mapping fails

["Cédric Le Goater" <clg@redhat.com>]

On 2/6/25 14:14, Cédric Le Goater wrote:
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> 
> Hello,
> 
> Under certain circumstances, a MMIO region of a device fails to map
> because the region is outside the supported IOVA ranges of the VM. In
> this case, PCI peer-to-peer transactions on BARs are not supported.
> This typically occurs when the IOMMU address space width is less than
> the physical address width, as can be the case on some Intel consumer
> processors or when using a vIOMMU device with default settings.
> 
> This series tries to clarify the error message reported to the user.
> 
> Thanks,
> 
> C.
> 
> Changes in v3:
> 
>   - Fixed warn_report_err_once()
>   - Improved commit logs a bit
>   - Dropped check on compatibility of CPU and IOMMU address space
>     width. Will address later in its own series.
> 
> Changes in v2:
> 
>   - Removed advice on how to resolve the issue. Diagnostic is enough.
>   - Introduced helpers
>   - Checked device type, since this only applies to PCI
>   - Added cleanup
>   
> Cédric Le Goater (7):
>    util/error: Introduce warn_report_err_once()
>    vfio/pci: Replace "iommu_device" by "vIOMMU"
>    vfio: Rephrase comment in vfio_listener_region_add() error path
>    vfio: Introduce vfio_get_vfio_device()
>    vfio: Improve error reporting when MMIO region mapping fails
>    vfio: Remove reports of DMA mapping errors in backends
>    vfio: Remove superfluous error report in vfio_listener_region_add()
> 
>   include/hw/vfio/vfio-common.h |  1 +
>   include/qapi/error.h          | 12 +++++++++++
>   backends/iommufd.c            |  3 ---
>   hw/vfio/common.c              | 40 +++++++++++++++++++++++++----------
>   hw/vfio/container.c           |  2 --
>   hw/vfio/helpers.c             | 10 +++++++++
>   hw/vfio/pci.c                 |  2 +-
>   util/error.c                  | 11 ++++++++++
>   8 files changed, 64 insertions(+), 17 deletions(-)
> 


Applied to vfio-next.

Thanks,

C.