From: Chuck Lever <chuck.lever@xxxxxxxxxx> [ Upstream commit 5de55ce951a1466e31ff68a7bc6b0a7ce3cb5947 ] Dan Aloni reports that when a server disconnects abruptly, a few memory regions are left DMA mapped. Over time this leak could pin enough I/O resources to slow or even deadlock an NFS/RDMA client. I found that if a transport disconnects before pending Send and FastReg WRs can be posted, the to-be-registered MRs are stranded on the req's rl_registered list and never released -- since they weren't posted, there's no Send completion to DMA unmap them. Reported-by: Dan Aloni <dan@xxxxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/sunrpc/xprtrdma/verbs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 75c646743df3e..ca89f24a1590b 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -933,6 +933,8 @@ static void rpcrdma_req_reset(struct rpcrdma_req *req) rpcrdma_regbuf_dma_unmap(req->rl_sendbuf); rpcrdma_regbuf_dma_unmap(req->rl_recvbuf); + + frwr_reset(req); } /* ASSUMPTION: the rb_allreqs list is stable for the duration, -- 2.25.1
