Re: [PATCH v13 12/15] PCI/CXL: Reject reset with unsafe function scope

[Dave Jiang]

On 9/23/26 2:41 PM, Cheatham, Benjamin wrote:
> On 9/22/2026 3:39 AM, Srirangan Madhavan wrote:
>> The per-device PCI reset interface must not reset sibling functions.
>> Reject cxl_reset and cxl_bus for multifunction devices and PFs with
>> enabled VFs.
>>
>> Reported-by: Alex Williamson <alwilliamson@xxxxxxxxxx>
> 
> I'm not sure Reported-by is the right tag, I would expect a Suggested-by instead. I think Reported-by
> is really more for bug fixes, but I could be wrong.

Yes Suggested-by is the right tag. 

DJ

> 
> Thanks,
> Ben
> 
>> Link: https://lore.kernel.org/linux-cxl/20260626160846.426e71b6@xxxxxxxxxx/
>> Link: https://lore.kernel.org/linux-cxl/6a50441e2bb5e_3cabcb1003e@djbw-dev.notmuch/
>> Signed-off-by: Srirangan Madhavan <smadhavan@xxxxxxxxxx>
>> ---
>>  drivers/cxl/core/resource.c | 3 +++
>>  drivers/pci/pci.c           | 3 +++
>>  2 files changed, 6 insertions(+)
>>
>> diff --git a/drivers/cxl/core/resource.c b/drivers/cxl/core/resource.c
>> index 85a554b6236c..249b1280f3d3 100644
>> --- a/drivers/cxl/core/resource.c
>> +++ b/drivers/cxl/core/resource.c
>> @@ -859,6 +859,9 @@ int cxl_reset_function(struct pci_dev *pdev, bool probe)
>>  	    !(ctrl & PCI_DVSEC_CXL_MEM_ENABLE))
>>  		return -ENOTTY;
>>  
>> +	if (pdev->multifunction || pci_num_vf(pdev))
>> +		return -ENOTTY;
>> +
>>  	if (probe)
>>  		return 0;
>>  
>> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
>> index b2879a6be5f8..fe611340f5ab 100644
>> --- a/drivers/pci/pci.c
>> +++ b/drivers/pci/pci.c
>> @@ -5026,6 +5026,9 @@ static int cxl_reset_bus_function(struct pci_dev *dev, bool probe)
>>  	if (!dvsec)
>>  		return -ENOTTY;
>>  
>> +	if (dev->multifunction || pci_num_vf(dev))
>> +		return -ENOTTY;
>> +
>>  	if (probe)
>>  		return 0;
>>  
>