Re: [PATCH v3 8/8] vfio/pci: Add the support for PCI D3cold state

Abhishek Sahu
2022-05-12T12:27:26Z

On 5/10/2022 7:00 PM, Jason Gunthorpe wrote:
> On Tue, May 10, 2022 at 06:56:02PM +0530, Abhishek Sahu wrote:
>>> We can add a directive to enforce an alignment regardless of the field
>>> size. I believe the feature ioctl header is already going to be eight
>>> byte aligned, so it's probably not strictly necessary, but Jason seems
>>> to be adding more of these directives elsewhere, so probably a good
>>> idea regardless. Thanks,
>
>> So, should I change it like
>>
>> __u8 low_power_state __attribute__((aligned(8)));
>>
>> Or
>>
>> __aligned_u64 low_power_state
>
> You should be explicit about padding, add a reserved to cover the gap.
>
> Jasno

Thanks Jason.

So, I need to make it like following. Correct ?

__u8 low_power_state;
__u8 reserved[7];

It seems, then this aligned attribute should not be required.

Thanks,
Abhishek