Background for this series is the following bug report, which is about a
crash with virtio-blk + iothread and request resubmission for werror/rerror:
https://bugzilla.redhat.com/show_bug.cgi?id=1671173
The reason is that bdrv_set_aio_context() didn't correctly quiesce
everything. Instead, it had a local hack to call aio_poll() for the
source AioContext, which covered some, but not all cases, and is wrong
because you can only call aio_poll() from the home thread.
So this series tries to make bdrv_drain() actually drain the known cases
(fixes virtio-blk and the NBD client) and use the regular drain
functions in bdrv_set_aio_context() instead of open-coding something
similar.
Kevin Wolf (12):
block-backend: Make blk_inc/dec_in_flight public
virtio-blk: Increase in_flight for request restart BH
nbd: Restrict connection_co reentrance
io: Make qio_channel_yield() interruptible
nbd: Move nbd_read_eof() to nbd/client.c
nbd: Use low-level QIOChannel API in nbd_read_eof()
nbd: Increase bs->in_flight during AioContext switch
block: Don't poll in bdrv_set_aio_context()
block: Fix AioContext switch for drained node
test-bdrv-drain: AioContext switch in drained section
block: Use normal drain for bdrv_set_aio_context()
aio-posix: Assert that aio_poll() is always called in home thread
block/nbd-client.h | 2 ++
include/block/nbd.h | 4 ++-
include/io/channel.h | 9 +++--
include/sysemu/block-backend.h | 2 ++
nbd/nbd-internal.h | 19 ----------
block.c | 25 +++++++-------
block/block-backend.c | 4 +--
block/nbd-client.c | 27 ++++++++++++++-
hw/block/virtio-blk.c | 4 +++
io/channel.c | 10 ++++++
nbd/client.c | 63 ++++++++++++++++++++++++++++++++--
tests/test-bdrv-drain.c | 32 +++++++++++++++++
util/aio-posix.c | 3 +-
13 files changed, 162 insertions(+), 42 deletions(-)
--
2.20.1