Let us consider the following process:
1. one fabric connect request A comes but the subsystem is paused
due to adding/removing ns or other operations, so this request A
will be put into sgroup->queued until the subsystem becomes active;
2. the subsystem is paused for a long time until the connect timeout,
related qpair is destroyed, the sgroup->queued will not be cleaned
because qpair's ctrlr is NULL;
3. if a new request B comes, it is more likely to be allocated to the
same memory as the previous fabric command request. And it will be
put into sgroup->queued again, where has already exists the exactly
same pointer with request B.
This leads to the pointer hanging problem and it will cause infinitely
loop when traversing sgroup->queued!
So this patch avoids the ptr-hanging problem by checking and cleaning
all sgroups queued req whose qpair is the being destroyed qpair in
_nvmf_qpair_destroy when ctrlr is NULL.
This problem is already described in issue #2133.
Signed-off-by: Peng Lian<peng.lian@smartx.com>
Change-Id: I909d673b5050f21fa193914cc4ffe6634232fa7d
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/17147
Community-CI: Mellanox Build Bot
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Konrad Sztyber <konrad.sztyber@intel.com>
b13ee3005d