xprtrdma: Pre-mark remotely invalidated MRs
There are rare cases where an rpcrdma_req and its matched
rpcrdma_rep can be re-used, via rpcrdma_buffer_put, while the RPC
reply handler is still using that req. This is typically due to a
signal firing at just the wrong instant.
As part of closing this race window, avoid using the wrong
rpcrdma_rep to detect remotely invalidated MRs. Mark MRs as
invalidated while we are sure the rep is still OK to use.
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=305
Fixes: 68791649a725 ('xprtrdma: Invalidate in the RPC reply ... ')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c
index f81dd93..31290cb 100644
--- a/net/sunrpc/xprtrdma/frwr_ops.c
+++ b/net/sunrpc/xprtrdma/frwr_ops.c
@@ -464,7 +464,6 @@
frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
{
struct ib_send_wr *first, **prev, *last, *bad_wr;
- struct rpcrdma_rep *rep = req->rl_reply;
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
struct rpcrdma_frmr *f;
struct rpcrdma_mw *mw;
@@ -483,8 +482,7 @@
list_for_each_entry(mw, &req->rl_registered, mw_list) {
mw->frmr.fr_state = FRMR_IS_INVALID;
- if ((rep->rr_wc_flags & IB_WC_WITH_INVALIDATE) &&
- (mw->mw_handle == rep->rr_inv_rkey))
+ if (mw->mw_flags & RPCRDMA_MW_F_RI)
continue;
f = &mw->frmr;