On Tue, Mar 10, 2020 at 12:38:29 +0100, Kevin Wolf wrote: > external_snapshot_prepare() tries to move the overlay to the AioContext > of the backing file (the snapshotted node). However, it's possible that > this doesn't work, but the backing file can instead be moved to the > overlay's AioContext (e.g. opening the backing chain for a mirror > target). > > bdrv_append() already indirectly uses bdrv_attach_node(), which takes > care to move nodes to make sure they use the same AioContext and which > tries both directions. > > So the problem has a simple fix: Just delete the unnecessary extra > bdrv_try_set_aio_context() call in external_snapshot_prepare() and > instead assert in bdrv_append() that both nodes were indeed moved to the > same AioContext. > > Signed-off-by: Kevin Wolf <kw...@redhat.com> > --- > block.c | 1 + > blockdev.c | 16 ---------------- > 2 files changed, 1 insertion(+), 16 deletions(-)
Tested-by: Peter Krempa <pkre...@redhat.com> Unfortunately I don't feel confident enough in the intricacies of the aio contexts. Nevertheless Fixing bugs by deleting code is awesome!
