On Thu, Feb 08, 2024 at 10:07:44AM -0300, Fabiano Rosas wrote:
> > diff --git a/migration/migration.c b/migration/migration.c
> > index
> > d5f705ceef4c925589aa49335969672c0d761fa2..5f55af3d7624750ca416c4177781241b3e291e5d
> > 100644
> > --- a/migration/migration.c
> > +++ b/migration/migration.c
> > @@ -2372,8 +2372,7 @@ static bool
> > close_return_path_on_source(MigrationState *ms)
> > * cause it to unblock if it's stuck waiting for the destination.
> > */
> > WITH_QEMU_LOCK_GUARD(&ms->qemu_file_lock) {
> > - if (ms->to_dst_file && ms->rp_state.from_dst_file &&
> > - qemu_file_get_error(ms->to_dst_file)) {
> > + if (migrate_has_error(ms) && ms->rp_state.from_dst_file) {
> > qemu_file_shutdown(ms->rp_state.from_dst_file);
> > }
> > }
>
> Hm, maybe Peter can help defend this, but this assumes that every
> function that takes an 'f' and sets the file error also sets
> migrate_set_error(). I'm not sure we have determined that, have we?
[apologies on getting back to this thread late.. I saw there's yet another
proposal in the other email, will look at that soon]
I think that should be set, or otherwise we lose an error? After all
s->error is the only thing we report, if there is a qemufile error that is
not reported into s->error it can be lost then.
On src QEMU we have both migration thread and return path thread. For
migration thread the file error should always be collected by
migration_detect_error() by the qemu_file_get_error_obj_any() (it also
looks after postcopy_qemufile_src). For return path thread it's always
collected when the loop quits.
Would migrate_has_error() be safer than qemu_file_get_error() in some
cases? I'm considering when there is an error outside of qemufile itself,
that's the case where qemu_file_get_error(ms->to_dst_file) can return
false, however we may still need a kick to the from_dst_file?
--
Peter Xu
