When device has more than one open descriptor, remove_cbs of particular
descriptors could be called more than once.
Consider the following scenario:
bdev X with 2 open descriptors A and B.
X is removed (hotremoved for instance)
bdev_unregister(X) is called
* bdev->status = REMOVING
* A->remove_cb is called
* some poller is started
* B->remove_cb is called
* another poller started
* poller from A->remove_cb finishes it's work and closes the desc:
* bdev_close(A)
* A is removed from bdev->open_descs list
* bdev->status is REMOVING, so bdev_unregister(X) is called again!
* B->remove cb is called again!
* another poller starts? segfault?
Fixes: 57d174ff67 ("bdev: add spdk_bdev_open/close")
Change-Id: I0a898ec0aee521d0b2a1168fe7d469cc41a8ef4f
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/369727
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
32f86a5f34