[libvirt] [PATCH] qemu: Check QEMU error on failed migration

[Jiri Denemark]

On Mon, Oct 16, 2017 at 17:18:58 +0200, Pavel Hrdina wrote:
> On Thu, Oct 12, 2017 at 03:48:29PM +0200, Jiri Denemark wrote:
> > When migration fails, QEMU may provide a description of the error in
> > the reply to query-migrate QMP command. We can fetch this error and use
> > it instead of the generic "unexpectedly failed" message.
> > 
> > Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
...
> > -    if (qemuMonitorJSONGetMigrationStats(qemuMonitorTestGetMonitor(test), &stats) < 0)
> > +    if (qemuMonitorJSONGetMigrationStats(qemuMonitorTestGetMonitor(test),
> > +                                         &stats, &error) < 0)
> >          goto cleanup;
> >  
> > -    if (memcmp(&stats, &expectedStats, sizeof(stats)) != 0) {
> > +    if (memcmp(&stats, &expectedStats, sizeof(stats)) != 0 || error) {
> >          virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> > -                       "Invalid migration status");
> > +                       "Invalid migration statistics");
> > +        goto cleanup;
> > +    }
> 
> Do we need to pass the "&error" for the first call of
> qemuMonitorJSONGetMigrationStats() since we know the answer?

Well, this is true for all tests. This is just testing that error stays
unset if there's no error reported by QEMU.

> 
> > +
> > +    memset(&stats, 0, sizeof(stats));
> > +    if (qemuMonitorJSONGetMigrationStats(qemuMonitorTestGetMonitor(test),
> > +                                         &stats, &error) < 0)
> > +        goto cleanup;
> > +
> > +    if (stats.status != QEMU_MONITOR_MIGRATION_STATUS_ERROR ||
> > +        STRNEQ_NULLABLE(error, "It's broken")) {
> > +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> > +                       "Invalid failed migration status");
> >          goto cleanup;
> >      }
> >  
> >      ret = 0;
> >   cleanup:
> >      qemuMonitorTestFree(test);
> > +    VIR_FREE(error);
> >      return ret;
> >  }
> 
> Reviewed-by: Pavel Hrdina <phrdina at redhat.com>

Thanks, pushed.

Jirka