[PATCH v4 0/3] Fix some AIO context locking in jobs

[Stefan Reiter]

Contains three seperate but related patches cleaning up and fixing some
issues regarding aio_context_acquire/aio_context_release for jobs. Mostly
affects blockjobs running for devices that have IO threads enabled AFAICT.

This is based on the discussions here:
https://lists.gnu.org/archive/html/qemu-devel/2020-03/msg07929.html

Changes from v3:
* commit_job appears to be unset in certain cases when replication_close is
  called, only access when necessary to avoid SIGSEGV

Missed this when shuffling around patches, sorry for noise with still-broken v3.

Changes from v2:
* reordered patch 1 to the end to not introduce temporary breakages
* added more fixes to job txn patch (should now pass the tests)

Changes from v1:
* fixed commit message for patch 1
* added patches 2 and 3


qemu: Stefan Reiter (3):
  job: take each job's lock individually in job_txn_apply
  replication: acquire aio context before calling job_cancel_sync
  backup: don't acquire aio_context in backup_clean

 block/backup.c        |  4 ----
 block/replication.c   |  8 +++++++-
 job.c                 | 48 ++++++++++++++++++++++++++++++++++---------
 tests/test-blockjob.c |  2 ++
 4 files changed, 47 insertions(+), 15 deletions(-)

-- 
2.26.0