[libvirt] [PATCH 04/10] qemu: blockjob: Fix deadlock when terminating job with invalid data

[Peter Krempa]

We must exit the monitor prior to refusing other work, otherwise the VM
object will become unusable.

This bug was introduced in commit v5.5.0-244-gc412383796 but thankfully
the code path was not excercised without QEMU_CAPS_BLOCKDEV.

Signed-off-by: Peter Krempa <pkrempa at redhat.com>
---
 src/qemu/qemu_blockjob.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/qemu/qemu_blockjob.c b/src/qemu/qemu_blockjob.c
index 2283d49c61..818e36435c 100644
--- a/src/qemu/qemu_blockjob.c
+++ b/src/qemu/qemu_blockjob.c
@@ -1305,14 +1305,14 @@ qemuBlockJobEventProcessConcluded(qemuBlockJobDataPtr job,
             dismissed = true;
     }

+    if (qemuDomainObjExitMonitor(driver, vm) < 0 || rc < 0)
+        goto cleanup;
+
     if (job->invalidData) {
         VIR_WARN("terminating job '%s' with invalid data", job->name);
         goto cleanup;
     }

-    if (qemuDomainObjExitMonitor(driver, vm) < 0 || rc < 0)
-        goto cleanup;
-
     if ((job->newstate == QEMU_BLOCKJOB_STATE_COMPLETED ||
          job->newstate == QEMU_BLOCKJOB_STATE_FAILED) &&
         job->state == QEMU_BLOCKJOB_STATE_ABORTING)
-- 
2.23.0