Prasad, On Tue, Oct 29, 2024 at 08:39:05PM +0530, Prasad Pandit wrote: > @@ -1612,6 +1615,10 @@ postcopy_preempt_send_channel_done(MigrationState *s, > * postcopy_qemufile_src to know whether it failed or not. > */ > qemu_sem_post(&s->postcopy_qemufile_src_sem); > + > + /* Send magic value to identify postcopy channel on the destination */ > + uint32_t magic = cpu_to_be32(POSTCOPY_MAGIC); > + qio_channel_write_all(ioc, (char *)&magic, sizeof(magic), NULL);
As we discussed internally, we can't do this unconditionally. We at least some compat properties. Or we need to see whether Fabiano's handshake can simplify this, because the handshake will also re-design the channel establishment protocol. Thanks, > } > > static void > diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h > index a6df1b2811..49e2982558 100644 > --- a/migration/postcopy-ram.h > +++ b/migration/postcopy-ram.h > @@ -15,6 +15,9 @@ > > #include "qapi/qapi-types-migration.h" > > +/* Magic value to identify postcopy channel on the destination */ > +#define POSTCOPY_MAGIC 0x55667788U > + > /* Return true if the host supports everything we need to do postcopy-ram */ > bool postcopy_ram_supported_by_host(MigrationIncomingState *mis, > Error **errp); > -- > 2.47.0 > -- Peter Xu
