Re: [PATCH v16 06/10] PCI/CXL: Add RCH support to CXL handlers

[Bowman, Terry]

On 3/29/2026 7:31 PM, Dan Williams wrote:
> "PCI/CXL: Add RCH support to CXL handlers" makes it sounds like this is
> a brand new capability rather than converting old support to new
> infrastructure.
> 
> This is more:
> 
> PCI/CXL: Forward RCD errors to the CXL port error handler
> 
> Terry Bowman wrote:
>> Restricted CXL Host (RCH) error handling is not currently supported by the
>> CXL Port error handling flow.
> 
> It is awkward to reference brand new infrastructure in a series as
> legacy ("not currently supported"). It is useful to quickly set context.
> 
> "Now that the PCI core is prepared to forward CXL port errors via a
> kfifo and the CXL core is prepared to receive them, it allows for
> additional unification. Convert the existing "Restricted CXL Host" (CXL
> 1.x "RCH") error handling from custom error handlers in the "cxl_pci"
> driver to generic CXL port error handlers in the CXL core.> 

That does read better. I'll update the patch message with this.

>> Integrate the existing RCH error handling
>> into the new Port error handling.
>>
>> Update cxl_rch_handle_error_iter() to forward the RCH protocol error using
>> the AER-CXL kfifo.
>>
>> Update cxl_handle_proto_error() to begin the RCH error handling with a call
>> to cxl_handle_rdport_errors(). This function handles both correctable and
>> uncorrectable RCH protocol errors.
>>
>> Change the cxl_handle_rdport_errors() function parameter from a CXL device
>> state to a PCI device.
>>
>> Report the serial number of the RCD Endpoint in the RCH logging. This
>> is used to associate the RCH with the RCD in the logs.
>>
>> Signed-off-by: Terry Bowman <terry.bowman@xxxxxxx>
> 
> Patch looks ok, but it will cause some adjustments to the fixup patch I
> shared against patch5. I still need to rebase all my proposed fixups to
> the end of this series.

Thanks for reviewing Dan.
- Terry