Re: [PATCH] RDMA/rxe: Fix a race condition related to the QP error state

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On Tue, 2018-01-09 at 11:23 -0800, Bart Van Assche wrote:
> The following sequence:
> * Change queue pair state into IB_QPS_ERR.
> * Post a work request on the queue pair.
> Triggers the following race condition in the rdma_rxe driver:
> * rxe_qp_error() triggers an asynchronous call of rxe_completer(), the function
>   that examines the QP send queue.
> * rxe_post_send() posts a work request on the QP send queue.
If rxe_completer() runs before rxe_post_send(), the send queue is
believed to be empty while a stale work request stays on the send queue
indefinitely.  To avoid this race, schedule rxe_completer() after a work
request is queued on a qp in the error state by rxe_post_send().

I think that improves the log message, yes?

-- 
Doug Ledford <dledford@xxxxxxxxxx>
    GPG KeyID: B826A3330E572FDD
    Key fingerprint = AE6B 1BDA 122B 23B4 265B  1274 B826 A333 0E57 2FDD

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