On Fri, 17 Jan 2014 14:38:16 -0500 Chuck Lever <chuck.lever@xxxxxxxxxx> wrote: > After commit a11a2bf4, "SUNRPC: Optimise away unnecessary data > moves in xdr_align_pages", Thu Aug 2 13:21:43 2012, READs larger > than a few hundred bytes via NFS/RDMA stopped working. This > commit exposed a long-standing bug in rpcrdma_inline_fixup(). > > I reproduce this with an rsize=4096 mount using the cthon04 > basic tests. Test 5 fails with an EIO error. > > For my reproducer, kernel log shows: > > NFS: server cheating in read reply: count 4096 > recvd 0 > > rpcrdma_inline_fixup() is zeroing the xdr_stream::page_len > field, and xdr_align_pages() is now returning that value to > the READ XDR decoder function. > > That field is set up by xdr_inline_pages() by the READ XDR > encoder function. As far as I can tell, it is supposed to > be left alone after that, as it describes the dimensions of > the reply xdr_stream, not the contents of that stream. > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=68391 > Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> > Cc: <stable@xxxxxxxxxxxxxxx> # 3.7+ > --- > > net/sunrpc/xprtrdma/rpc_rdma.c | 4 +--- > 1 files changed, 1 insertions(+), 3 deletions(-) > > diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c > index e03725b..96ead52 100644 > --- a/net/sunrpc/xprtrdma/rpc_rdma.c > +++ b/net/sunrpc/xprtrdma/rpc_rdma.c > @@ -649,9 +649,7 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad) > break; > page_base = 0; > } > - rqst->rq_rcv_buf.page_len = olen - copy_len; > - } else > - rqst->rq_rcv_buf.page_len = 0; > + } > > if (copy_len && rqst->rq_rcv_buf.tail[0].iov_len) { > curlen = copy_len; > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html Seems to fix the bug for me too... Tested-by: Jeff Layton <jlayton@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
