Re: [Qemu-devel] [RFC 1/3] pvh: Add x86/HVM direct boot ABI header file

[Liam Merwick]

On 11/12/2018 14:57, Liam Merwick wrote:
> On 11/12/2018 14:01, Stefan Hajnoczi wrote:
> > On Wed, Dec 05, 2018 at 10:37:24PM +0000, Liam Merwick wrote:
> > > From: Liam Merwick <address@hidden>
> > >
> > > The x86/HVM direct boot ABI permits Qemu to be able to boot directly
> > > into the uncompressed Linux kernel binary without the need to run 
> > > firmware.
> > >
> > >     https://xenbits.xen.org/docs/unstable/misc/pvh.html
> > >
> > > This commit adds the header file that defines the start_info struct
> > > that needs to be populated in order to use this ABI.
> > >
> > > Signed-off-by: Maran Wilson <address@hidden>
> > > Signed-off-by: Liam Merwick <address@hidden>
> > > Reviewed-by: Konrad Rzeszutek Wilk <address@hidden>
> > > ---
> > >   include/hw/xen/start_info.h | 146 
> > > ++++++++++++++++++++++++++++++++++++++++++++
> > >   1 file changed, 146 insertions(+)
> > >   create mode 100644 include/hw/xen/start_info.h
> >
> > Does it make sense to bring in Linux
> > include/xen/interface/hvm/start_info.h via QEMU's
> > include/standard-headers/?
> >
> > QEMU has a script in scripts/update-linux-header.sh for syncing Linux
> > headers into include/standard-headers/.  This makes it easy to keep
> > Linux header files up-to-date.  We basically treat files in
> > include/standard-headers/ as auto-generated.
> >
> > If you define start_info.h yourself without using
> > include/standard-headers/, then it won't be synced with Linux.
>
> That does seem better.  I will make that change.

When attempting to implement this, I found the canonical copy of this 
header file is actually in Xen and the Linux copy is kept in sync with 
that.  Also, 'make headers_install' doesn't install those Xen headers.

Instead I updated the commit comment to mention the canonical copy 
location.  This file isn't expected to change much so I think keeping it 
in sync in future shouldn't be onerous.

Regards,
Liam