Re: [PATCH 1/3] virtio: Basic implementation of virtio pstore driver

[Namhyung Kim <namhyung@kernel.org>]

On Tue, Nov 15, 2016 at 07:06:28AM +0200, Michael S. Tsirkin wrote:
> On Tue, Nov 15, 2016 at 01:50:21PM +0900, Namhyung Kim wrote:
> > On Thu, Nov 10, 2016 at 06:39:55PM +0200, Michael S. Tsirkin wrote:
> > [SNIP]
> > > > +struct virtio_pstore_fileinfo {
> > > > +	__virtio64		id;
> > > > +	__virtio32		count;
> > > > +	__virtio16		type;
> > > > +	__virtio16		unused;
> > > > +	__virtio32		flags;
> > > > +	__virtio32		len;
> > > > +	__virtio64		time_sec;
> > > > +	__virtio32		time_nsec;
> > > > +	__virtio32		reserved;
> > > > +};
> > > > +
> > > > +struct virtio_pstore_config {
> > > > +	__virtio32		bufsize;
> > > > +};
> > > > +
> > > 
> > > What exactly does each field mean? I'm especially
> > > interested in time fields - maintaining a consistent
> > > time between host and guest is not a simple problem.
> > 
> > These are required by pstore and will be used to create corresponding
> > files in the pstore filesystem.  The time fields are for mtime and
> > ctime and, I think, it's just a hint for user and doesn't require
> > strict consistency.
> 
> Pls add documentation. I would just drop hints for now.

Well, I'll add docmentation.  But I think just dropping might not good
since they all have host time and it's helpful to know their relative
difference in guest.

Thanks,
Namhyung