[libvirt] [PATCH 3/3] qemu: Properly abort migration to a file

[Jiri Denemark]

On Thu, May 22, 2014 at 16:14:22 +0200, Peter Krempa wrote:
> On 05/22/14 13:55, Jiri Denemark wrote:
> > This is similar to the previous commit in that we need to explicitly
> > send migrate_cancel when libvirt detects an error other than those
> > reported by query-migrate. However, the possibility to hit such error is
> > pretty small.
> > 
> > Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
> > ---
> >  src/qemu/qemu_migration.c | 21 ++++++++++++++++++++-
> >  1 file changed, 20 insertions(+), 1 deletion(-)
> > 
> > diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
> > index ae18acb..5754f73 100644
> > --- a/src/qemu/qemu_migration.c
> > +++ b/src/qemu/qemu_migration.c
> > @@ -4704,6 +4704,7 @@ qemuMigrationToFile(virQEMUDriverPtr driver, virDomainObjPtr vm,
> >      int pipeFD[2] = { -1, -1 };
> >      unsigned long saveMigBandwidth = priv->migMaxBandwidth;
> >      char *errbuf = NULL;
> > +    virErrorPtr orig_err = NULL;
> >  
> >      /* Increase migration bandwidth to unlimited since target is a file.
> >       * Failure to change migration speed is not fatal. */
> > @@ -4806,8 +4807,17 @@ qemuMigrationToFile(virQEMUDriverPtr driver, virDomainObjPtr vm,
> >  
> >      rc = qemuMigrationWaitForCompletion(driver, vm, asyncJob, NULL, false);
> >  
> > -    if (rc < 0)
> > +    if (rc < 0) {
> > +        if (rc == -2) {
> > +            orig_err = virSaveLastError();
> > +            virCommandAbort(cmd);
> 
> Shouldn't we abort the migration in qemu before killing the I/O helper?
> Qemu will get a sigpipe probably after we do that. Not sure wether
> that's worth dealing with as the migration is still going to fail.

Hmm, good question. Do we even need to abort I/O helper as I guess
cancelling the migration will result in EOF on the I/O helper's input?

> > +            if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) == 0) {
> > +                qemuMonitorMigrateCancel(priv->mon);
> > +                qemuDomainObjExitMonitor(driver, vm);
> > +            }
> > +        }

Jirka