Re: [PATCH v10 08/12] cxl: Reject CXL Reset on multifunction devices

[Dave Jiang]

On 8/4/26 12:29 PM, Srirangan Madhavan wrote:
> CXL Reset can be exposed as a PCI function reset method only when the
> reset is function-scoped. PCI reset-method probing runs during
> enumeration, so walking sibling functions there can race with functions
> that have not been added to the bus yet.
> 
> Reject multifunction devices for now instead of trying to infer reset
> scope from sibling state. Systems that can prove a multifunction device
> has function-scoped CXL Reset can be enabled later.
> 
> Signed-off-by: Srirangan Madhavan <smadhavan@xxxxxxxxxx>

Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>

> ---
>  drivers/cxl/core/resource.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/cxl/core/resource.c b/drivers/cxl/core/resource.c
> index 6d4528f77c53..464ca9bdae05 100644
> --- a/drivers/cxl/core/resource.c
> +++ b/drivers/cxl/core/resource.c
> @@ -979,6 +979,9 @@ int cxl_reset_function(struct pci_dev *pdev, bool probe)
>  	if (dvsec < 0)
>  		return dvsec;
>  
> +	if (pdev->multifunction)
> +		return -ENOTTY;
> +
>  	if (probe)
>  		return 0;
>