On Mon, Mar 05, 2018 at 05:42:42PM +0000, Dr. David Alan Gilbert wrote:
> * Peter Xu (pet...@redhat.com) wrote:
> > On Fri, Feb 16, 2018 at 01:16:07PM +0000, Dr. David Alan Gilbert (git)
> > wrote:
> >
> > [...]
> >
> > > typedef struct VuVirtqElement {
> > > diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt
> > > index 621543e654..bdec9ec0e8 100644
> > > --- a/docs/interop/vhost-user.txt
> > > +++ b/docs/interop/vhost-user.txt
> > > @@ -682,6 +682,12 @@ Master message types
> > > the slave must open a userfaultfd for later use.
> > > Note that at this stage the migration is still in precopy mode.
> > >
> > > + * VHOST_USER_POSTCOPY_LISTEN
> > > + Id: 27
> > > + Master payload: N/A
> > > +
> > > + Master advises slave that a transition to postcopy mode has
> > > happened.
> >
> > Could we add something to explain why this listen needs to be
> > broadcasted to clients? Since I failed to find it out quickly
> > myself. :(
>
> I've changed this to:
>
> * VHOST_USER_POSTCOPY_LISTEN
> Id: 29
> Master payload: N/A
>
> Master advises slave that a transition to postcopy mode has happened.
> The slave must ensure that shared memory is registered with userfaultfd
> to cause faulting of non-present pages.
But shouldn't this be assured by the SET_MEM_TABLE call?
Sorry for being not that familiar with vhost-user protocol... but
what's the correct order of these commands?
POSTCOPY_ADVISE
POSTCOPY_LISTEN
SET_MEM_TABLE
? Thanks,
>
> This is always sent sometime after a VHOST_USER_POSTCOPY_ADVISE, and
> thus only when VHOST_USER_PROTOCOL_F_PAGEFAULT is supported.
>
> Dave
>
> > --
> > Peter Xu
> --
> Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
--
Peter Xu
