----- Original Message -----
> From: "Greg KH" <gregkh@xxxxxxxxxxxxxxxxxxx>
> To: "Aaron Sierra" <asierra@xxxxxxxxxxx>
> Cc: "martyn welch" <martyn.welch@xxxxxx>, devel@xxxxxxxxxxxxxxxxxxxx, "manohar vanga" <manohar.vanga@xxxxxxxxx>, "dan
> carpenter" <dan.carpenter@xxxxxxxxxx>
> Sent: Tuesday, December 17, 2013 7:06:06 PM
> Subject: Re: [PATCH v2] vme_user: Update API to work in mixed environments
>
> On Mon, Dec 09, 2013 at 10:05:40AM -0600, Aaron Sierra wrote:
> > This patch updates the vme_master and vme_slave structures to use
> > types with well defined size and to prevent the compiler from
> > inserting padding (between enable and vme_addr for one).
> >
> > The original vme_master and vme_slave structs would be different
> > sizes and have different layouts depending on whether they were built
> > for a 32-bit or 64-bit system.
> >
> > On x86 it is possible to have a 32-bit userspace and a 64-bit kernel.
> > In this type of environment, the userspace and kernel vme_user APIs
> > would disagree and prevent ioctls from executing (based on ioctl
> > signatures from _IOR and _IOW).
> >
> > Signed-off-by: Aaron Sierra <asierra@xxxxxxxxxxx>
> > Acked-by: Martyn Welch <martyn.welch@xxxxxx>
> > ---
> > drivers/staging/vme/devices/vme_user.h | 20 ++++++++++----------
> > 1 file changed, 10 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/staging/vme/devices/vme_user.h
> > b/drivers/staging/vme/devices/vme_user.h
> > index 280ccc7..c3b4964 100644
> > --- a/drivers/staging/vme/devices/vme_user.h
> > +++ b/drivers/staging/vme/devices/vme_user.h
> > @@ -7,10 +7,10 @@
> > * VMEbus Master Window Configuration Structure
> > */
> > struct vme_master {
> > - int enable; /* State of Window */
> > - unsigned long long vme_addr; /* Starting Address on the VMEbus */
> > - unsigned long long size; /* Window Size */
> > - u32 aspace; /* Address Space */
> > + u32 enable; /* State of Window */
> > + u64 vme_addr; /* Starting Address on the VMEbus */
> > + u64 size; /* Window Size */
> > + u32 aspace; /* Address Space */
>
> Variable types that cross the user/kernel boundry need to have "__" in
> the front of them. SO these need to be "__u32", "__u64" and the like.
> Care to send a patch that fixes this as an add-on to this one (I'll take
> this one as it's good on it's own.)
>
> thanks,
>
> greg k-h
>
Sure thing. Thanks, Greg.
-Aaron
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