SUNRPC: The RDMA back channel mustn't disappear while requests are outstanding

If there are RDMA back channel requests being processed by the
server threads, then we should hold a reference to the transport
to ensure it doesn't get freed from underneath us.

Reported-by: Neil Brown <neilb@suse.de>
Fixes: 63cae47005 ("xprtrdma: Handle incoming backward direction RPC calls")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Trond Myklebust 2019-10-17 09:02:20 -04:00 committed by Anna Schumaker
parent 875f0706ac
commit 9edb455e67

View File

@ -163,6 +163,7 @@ void xprt_rdma_bc_free_rqst(struct rpc_rqst *rqst)
spin_lock(&xprt->bc_pa_lock);
list_add_tail(&rqst->rq_bc_pa_list, &xprt->bc_pa_list);
spin_unlock(&xprt->bc_pa_lock);
xprt_put(xprt);
}
static struct rpc_rqst *rpcrdma_bc_rqst_get(struct rpcrdma_xprt *r_xprt)
@ -259,6 +260,7 @@ void rpcrdma_bc_receive_call(struct rpcrdma_xprt *r_xprt,
/* Queue rqst for ULP's callback service */
bc_serv = xprt->bc_serv;
xprt_get(xprt);
spin_lock(&bc_serv->sv_cb_lock);
list_add(&rqst->rq_bc_list, &bc_serv->sv_cb_list);
spin_unlock(&bc_serv->sv_cb_lock);