[Qemu-devel] [PATCH 0/2] vl: Drain before (block) job cancel when quitting

[Max Reitz <mreitz@redhat.com>]

Quitting qemu should lead to qemu exiting pretty much immediately.  That
means if you have a block job running on a throttled block node, the
node should ignore its throttling and the job should be cancelled
immediately.

Unfortunately, that is not what happens.  Currently, the node will be
drained (with a bdrv_drain_all()), and then again unquiesced (because
bdrv_drain_all() ends).  Then, the block job is cancelled; but at this
point, the node is no longer drained, so it will block, as it befits a
throttling node.

To fix this issue, we have to keep all nodes drained while we cancel all
block jobs when quitting qemu.  This will make the throttle node ignore
its throttling and thus let the block job cancel immediately.


Max Reitz (2):
  vl: Drain before (block) job cancel when quitting
  iotests: Test quitting with job on throttled node

 vl.c                       | 11 ++++++++
 tests/qemu-iotests/218     | 55 ++++++++++++++++++++++++++++++++++++--
 tests/qemu-iotests/218.out |  4 +++
 3 files changed, 68 insertions(+), 2 deletions(-)

-- 
2.21.0