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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 10 May 2022 10:30:41 -0300
From:   Jason Gunthorpe <jgg@...dia.com>
To:     Abhishek Sahu <abhsahu@...dia.com>
Cc:     Alex Williamson <alex.williamson@...hat.com>,
        Cornelia Huck <cohuck@...hat.com>,
        Yishai Hadas <yishaih@...dia.com>,
        Shameer Kolothum <shameerali.kolothum.thodi@...wei.com>,
        Kevin Tian <kevin.tian@...el.com>,
        "Rafael J . Wysocki" <rafael@...nel.org>,
        Max Gurtovoy <mgurtovoy@...dia.com>,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        linux-pm@...r.kernel.org, linux-pci@...r.kernel.org
Subject: Re: [PATCH v3 8/8] vfio/pci: Add the support for PCI D3cold state

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