nvme: fix double blk_mq_complete_request for timeout request with low probability

When nvme_cancel_tagset traverses all tagsets and executes
nvme_cancel_request, this request may be executing blk_mq_free_request
that is called by nvme_rdma_complete_timed_out/nvme_tcp_complete_timed_out.
When blk_mq_free_request executes to WRITE_ONCE(rq->state, MQ_RQ_IDLE) and
__blk_mq_free_request(rq), it will cause double blk_mq_complete_request for
this request, and it will cause a null pointer error in the second
execution of this function because rq->mq_hctx has set to NULL in first
execution.

Signed-off-by: Lei Yin <[email protected]>
Reviewed-by: Keith Busch <[email protected]>
Reviewed-by: Sagi Grimberg <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>

0 files changed, 0 insertions, 0 deletions