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

From: Jason Gunthorpe
Date: Thu May 12 2022 - 08:47:46 EST


On Thu, May 12, 2022 at 05:57:05PM +0530, Abhishek Sahu wrote:
> 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.

Yes

Jason