[PATCH kernel] vfio_pci_nvlink2: Do not attempt NPU2 setup on old P8's NPU

[Andrew Donnellan]

On 13/11/20 4:06 pm, Alexey Kardashevskiy wrote:
> We execute certain NPU2 setup code (such as mapping an LPID to a device
> in NPU2) unconditionally if an Nvlink bridge is detected. However this
> cannot succeed on P8+ machines as the init helpers return an error other
> than ENODEV which means the device is there is and setup failed so
> vfio_pci_enable() fails and pass through is not possible.
> 
> This changes the two NPU2 related init helpers to return -ENODEV if
> there is no "memory-region" device tree property as this is
> the distinction between NPU and NPU2.
> 
> Fixes: 7f92891778df ("vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver")
> Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>

Should this be Cc: stable?


Andrew

-- 
Andrew Donnellan              OzLabs, ADL Canberra
ajd at linux.ibm.com             IBM Australia Limited