On 15/06/2017 18:54, Laurent Vivier wrote: > On 14/06/2017 09:55, Peter Xu wrote: >> 0425dc9 is actually v1 of that patch, but it was accidentally >> merged (while there was a v2). That will cause problem when we try to >> migrate to some old QEMUs when return path is not really there. Let's >> fix it, then squashing this patch with 0425dc9 will be exactly patch >> content of v2. >> >> Fixes: 0425dc9 ("migration: isolate return path on src") >> Signed-off-by: Peter Xu <pet...@redhat.com> >> --- >> migration/migration.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/migration/migration.c b/migration/migration.c >> index 8ef6d6c..f9053b0 100644 >> --- a/migration/migration.c >> +++ b/migration/migration.c >> @@ -1814,7 +1814,11 @@ static void *migration_thread(void *opaque) >> >> qemu_savevm_state_header(s->to_dst_file); >> >> - if (s->to_dst_file) { >> + /* >> + * If we opened the return path, we need to make sure dst has it >> + * opened as well. >> + */ >> + if (s->rp_state.from_dst_file) { >> /* Now tell the dest that it should open its end so it can reply */ >> qemu_savevm_send_open_return_path(s->to_dst_file); >> >> > > Tested-by: Laurent Vivier <lviv...@redhat.com> > > This also fixes migration of pseries guest, using the same > binary/machine type on both side, the error was: > > qemu-system-ppc64: Failed to load spapr_iommu:mig_table > qemu-system-ppc64: error while loading state for instance 0x80000001 of > device 'spapr_iommu' > qemu-system-ppc64: load of migration failed: Input/output error
The error is an IEO because the file descriptor is closed on source. It seems the source closes the stream too early without this patch. For test purpose, I have disabled the qemu_fclose() on the source, and the error disappears from the destination. Laurent