[kvm-unit-tests PATCH v1] arch-run: migration: properly handle crashing outgoing QEMU

[Nico Boehr <nrb@linux.ibm.com>]

When outgoing (live) QEMU crashes or times out during migration, we
currently hang forever.

This is because we don't exit the loop querying migration state when QMP
communication fails.

Add proper error handling to the loop and exit when QMP communication
fails for whatever reason.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
---
Sorry I accidentally sent this only to s390x maintainers and forgot
Paolo and Andrew, hence resending.

 scripts/arch-run.bash | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/scripts/arch-run.bash b/scripts/arch-run.bash
index 518607f4b75d..de9890408e24 100644
--- a/scripts/arch-run.bash
+++ b/scripts/arch-run.bash
@@ -162,8 +162,14 @@ run_migration ()
 	migstatus=`qmp ${qmp1} '"query-migrate"' | grep return`
 	while ! grep -q '"completed"' <<<"$migstatus" ; do
 		sleep 1
-		migstatus=`qmp ${qmp1} '"query-migrate"' | grep return`
-		if grep -q '"failed"' <<<"$migstatus" ; then
+		if ! migstatus=`qmp ${qmp1} '"query-migrate"'`; then
+			echo "ERROR: Querying migration state failed." >&2
+			echo > ${fifo}
+			qmp ${qmp2} '"quit"'> ${qmpout2} 2>/dev/null
+			return 2
+		fi
+		migstatus=`grep return <<<"$migstatus"`
+		if grep -q '"failed"' <<<"$migstatus"; then
 			echo "ERROR: Migration failed." >&2
 			echo > ${fifo}
 			qmp ${qmp1} '"quit"'> ${qmpout1} 2>/dev/null
-- 
2.41.0