From 01dde20ce04b3a18f1e91d6d1ee0ef484d20bbf2 Mon Sep 17 00:00:00 2001
From: Maciej Fijalkowski <maciejromanfijalkowski@gmail.com>
Date: Fri, 1 Feb 2019 22:42:27 +0100
Subject: [PATCH] xdp: Provide extack messages when prog attachment failed
In order to provide more meaningful messages to user when the process of
loading xdp program onto network interface failed, let's add extack
messages within dev_change_xdp_fd.
Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
net/core/dev.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/net/core/dev.c b/net/core/dev.c
index 8e276e0192a11..bfa4be42afff7 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -7983,8 +7983,10 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
query = flags & XDP_FLAGS_HW_MODE ? XDP_QUERY_PROG_HW : XDP_QUERY_PROG;
bpf_op = bpf_chk = ops->ndo_bpf;
- if (!bpf_op && (flags & (XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE)))
+ if (!bpf_op && (flags & (XDP_FLAGS_DRV_MODE | XDP_FLAGS_HW_MODE))) {
+ NL_SET_ERR_MSG(extack, "underlying driver does not support XDP in native mode");
return -EOPNOTSUPP;
+ }
if (!bpf_op || (flags & XDP_FLAGS_SKB_MODE))
bpf_op = generic_xdp_install;
if (bpf_op == bpf_chk)
@@ -7992,11 +7994,15 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
if (fd >= 0) {
if (__dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG) ||
- __dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG_HW))
+ __dev_xdp_query(dev, bpf_chk, XDP_QUERY_PROG_HW)) {
+ NL_SET_ERR_MSG(extack, "native and generic XDP can't be active at the same time");
return -EEXIST;
+ }
if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) &&
- __dev_xdp_query(dev, bpf_op, query))
+ __dev_xdp_query(dev, bpf_op, query)) {
+ NL_SET_ERR_MSG(extack, "XDP program already attached");
return -EBUSY;
+ }
prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP,
bpf_op == ops->ndo_bpf);