[Qemu-devel] [PATCH v3 0/4] dataplane snapshot fixes

["Denis V. Lunev" <den@openvz.org>]

with test
    while /bin/true ; do
        virsh snapshot-create rhel7
        sleep 10
        virsh snapshot-delete rhel7 --current
    done
with enabled iothreads on a running VM leads to a lot of troubles: hangs,
asserts, errors.

Anyway, I think that the construction like
    assert(aio_context_is_locked(aio_context));
should be widely used to ensure proper locking.

Changes from v2:
- droppped patch 5 as already merged
- changed locking scheme in patch 4 by suggestion of Juan

Changes from v1:
- aio-context locking added
- comment is rewritten

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>

  fifolock: create rfifolock_is_locked helper
  aio_context: create aio_context_is_locked helper
  io: add locking constraints check into bdrv_drain to ensure locking
  migration: add missed aio_context_acquire into hmp_savevm/hmp_delvm

 async.c                  |  5 +++++
 block/io.c               |  5 ++++-
 block/snapshot.c         |  5 +++++
 include/block/aio.h      |  3 +++
 include/qemu/rfifolock.h |  1 +
 migration/savevm.c       | 18 +++++++++++++++---
 util/rfifolock.c         |  9 +++++++--
 7 files changed, 40 insertions(+), 6 deletions(-)

-- 
2.1.4