When a bdev is registered, it is examined by the bdev modules before the
bdev register even is notified.
Examination may be asychronous, e.g. when the bdev module has to perform
I/O on the new bdev.
This causes a race condition where the bdev might be destroyed while
examination is not finished. Then, once all modules have signaled that
examination is done, `bdev_register_finished` makes an invalid access to
the freed bdev pointer.
To fix this, defer the unregistration until the examine is completed by
opening a descriptor on the bdev.
Change-Id: I79a2faa96c1c893fc1cee645fbe31f689b03ea4a
Signed-off-by: Nathan Claudel <nclaudel@kalray.eu>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/13630
Community-CI: Mellanox Build Bot
Reviewed-by: Shuhei Matsumoto <smatsumoto@nvidia.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Konrad Sztyber <konrad.sztyber@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
d0038b70df