Re: [PATCH] PCI/MSI: Initialize the prepare descriptor by default

[Naman Jain <namjain@linux.microsoft.com>]

On 7/8/2025 3:32 PM, Shradha Gupta wrote:
> On Tue, Jul 08, 2025 at 10:48:48AM +0530, Naman Jain wrote:
>> Plug the default MSI-X prepare descriptor for non-implemented ops by
>> default to workaround the inability of Hyper-V vPCI module to setup
>> the MSI-X descriptors properly; especially for dynamically allocated
>> MSI-X.
>>
>> Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
>> ---
>>   drivers/pci/msi/irqdomain.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
>> index 765312c92d9b..655e99b9c8cc 100644
>> --- a/drivers/pci/msi/irqdomain.c
>> +++ b/drivers/pci/msi/irqdomain.c
>> @@ -84,6 +84,8 @@ static void pci_msi_domain_update_dom_ops(struct msi_domain_info *info)
>>   	} else {
>>   		if (ops->set_desc == NULL)
>>   			ops->set_desc = pci_msi_domain_set_desc;
>> +		if (ops->prepare_desc == NULL)
>> +			ops->prepare_desc = pci_msix_prepare_desc;
>>   	}
>>   }
>>   
>>
>> base-commit: 26ffb3d6f02cd0935fb9fa3db897767beee1cb2a
>> -- 
>> 2.34.1
>>
> 
> Hey Naman,
> 
> can you please try your tests with this patch:
> https://lore.kernel.org/all/1749651015-9668-1-git-send-email-shradhagupta@linux.microsoft.com/
> I think this should help your use case
> 
> Regards,
> Shradha.

Hey,
Thanks for sharing this, this works for me.

Closing this thread.

Regards,
Naman