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From: kbuild test robot <lkp@intel.com>
To: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: kbuild-all@01.org, netdev@vger.kernel.org,
	jakub.kicinski@netronome.com,
	"Michael S. Tsirkin" <mst@redhat.com>,
	pavel.odintsov@gmail.com, Jason Wang <jasowang@redhat.com>,
	mchan@broadcom.com, John Fastabend <john.fastabend@gmail.com>,
	peter.waskiewicz.jr@intel.com,
	Jesper Dangaard Brouer <brouer@redhat.com>,
	Daniel Borkmann <borkmann@iogearbox.net>,
	Alexei Starovoitov <alexei.starovoitov@gmail.com>,
	Andy Gospodarek <andy@greyhouse.net>
Subject: Re: [net-next V4 PATCH 2/5] bpf: XDP_REDIRECT enable use of cpumap
Date: Fri, 6 Oct 2017 16:30:21 +0800	[thread overview]
Message-ID: <201710061621.e8zuSelY%fengguang.wu@intel.com> (raw)
In-Reply-To: <150711863012.9499.383645968070658124.stgit@firesoul>

[-- Attachment #1: Type: text/plain, Size: 15313 bytes --]

Hi Jesper,

[auto build test WARNING on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Jesper-Dangaard-Brouer/New-bpf-cpumap-type-for-XDP_REDIRECT/20171006-024959
config: um-allyesconfig (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
        # save the attached .config to linux build tree
        make ARCH=um 

Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings

All warnings (new ones prefixed by >>):

   Cyclomatic Complexity 4 net/core/filter.c:____bpf_skb_set_tunnel_opt
   Cyclomatic Complexity 1 net/core/filter.c:bpf_skb_set_tunnel_opt
   Cyclomatic Complexity 6 net/core/filter.c:____bpf_skb_under_cgroup
   Cyclomatic Complexity 1 net/core/filter.c:bpf_skb_under_cgroup
   Cyclomatic Complexity 3 net/core/filter.c:____bpf_xdp_event_output
   Cyclomatic Complexity 1 net/core/filter.c:bpf_xdp_event_output
   Cyclomatic Complexity 2 net/core/filter.c:____bpf_get_socket_cookie
   Cyclomatic Complexity 1 net/core/filter.c:bpf_get_socket_cookie
   Cyclomatic Complexity 3 net/core/filter.c:____bpf_get_socket_uid
   Cyclomatic Complexity 1 net/core/filter.c:bpf_get_socket_uid
   Cyclomatic Complexity 21 net/core/filter.c:____bpf_setsockopt
   Cyclomatic Complexity 1 net/core/filter.c:bpf_setsockopt
   Cyclomatic Complexity 10 net/core/filter.c:bpf_skb_is_valid_access
   Cyclomatic Complexity 4 net/core/filter.c:sk_filter_is_valid_access
   Cyclomatic Complexity 6 net/core/filter.c:lwt_is_valid_access
   Cyclomatic Complexity 7 net/core/filter.c:sock_filter_is_valid_access
   Cyclomatic Complexity 2 net/core/filter.c:bpf_unclone_prologue
   Cyclomatic Complexity 1 net/core/filter.c:tc_cls_act_prologue
   Cyclomatic Complexity 7 net/core/filter.c:tc_cls_act_is_valid_access
   Cyclomatic Complexity 4 net/core/filter.c:__is_valid_xdp_access
   Cyclomatic Complexity 5 net/core/filter.c:xdp_is_valid_access
   Cyclomatic Complexity 4 net/core/filter.c:__is_valid_sock_ops_access
   Cyclomatic Complexity 3 net/core/filter.c:sock_ops_is_valid_access
   Cyclomatic Complexity 1 net/core/filter.c:sk_skb_prologue
   Cyclomatic Complexity 6 net/core/filter.c:sk_skb_is_valid_access
   Cyclomatic Complexity 3 net/core/filter.c:__xdp_generic_ok_fwd_dev
   Cyclomatic Complexity 11 net/core/filter.c:sk_filter_trim_cap
   Cyclomatic Complexity 3 net/core/filter.c:bpf_skb_copy
   Cyclomatic Complexity 1 net/core/filter.c:bpf_xdp_copy
   Cyclomatic Complexity 2 net/core/filter.c:bpf_skb_grow_rcsum
   Cyclomatic Complexity 2 net/core/filter.c:sk_filter_release
   Cyclomatic Complexity 2 net/core/filter.c:bpf_release_orig_filter
   Cyclomatic Complexity 2 net/core/filter.c:__bpf_prog_release
   Cyclomatic Complexity 1 net/core/filter.c:__sk_filter_release
   Cyclomatic Complexity 2 net/core/filter.c:sk_filter_release_rcu
   Cyclomatic Complexity 1 net/core/filter.c:bpf_prog_destroy
   Cyclomatic Complexity 9 net/core/filter.c:check_load_and_stores
   Cyclomatic Complexity 19 net/core/filter.c:bpf_check_classic
   Cyclomatic Complexity 3 net/core/filter.c:bpf_prog_store_orig_filter
   Cyclomatic Complexity 10 net/core/filter.c:convert_skb_access
   Cyclomatic Complexity 24 net/core/filter.c:convert_bpf_extensions
   Cyclomatic Complexity 52 net/core/filter.c:bpf_convert_filter
   Cyclomatic Complexity 6 net/core/filter.c:bpf_migrate_filter
   Cyclomatic Complexity 5 net/core/filter.c:bpf_prepare_filter
   Cyclomatic Complexity 4 net/core/filter.c:bpf_prog_create
   Cyclomatic Complexity 7 net/core/filter.c:bpf_prog_create_from_user
   Cyclomatic Complexity 6 net/core/filter.c:__get_filter
   Cyclomatic Complexity 5 net/core/filter.c:bpf_warn_invalid_xdp_action
   Cyclomatic Complexity 7 net/core/filter.c:__reuseport_attach_prog
   Cyclomatic Complexity 2 net/core/filter.c:__get_bpf
   Cyclomatic Complexity 3 net/core/filter.c:__bpf_redirect_common
   Cyclomatic Complexity 2 net/core/filter.c:__bpf_redirect
   Cyclomatic Complexity 1 net/core/filter.c:bpf_skb_generic_push
   Cyclomatic Complexity 3 net/core/filter.c:bpf_skb_net_hdr_push
   Cyclomatic Complexity 5 net/core/filter.c:bpf_skb_proto_4_to_6
   Cyclomatic Complexity 4 net/core/filter.c:bpf_skb_net_grow
   Cyclomatic Complexity 2 net/core/filter.c:bpf_skb_generic_pop
   Cyclomatic Complexity 3 net/core/filter.c:bpf_skb_net_hdr_pop
   Cyclomatic Complexity 5 net/core/filter.c:bpf_skb_proto_6_to_4
   Cyclomatic Complexity 3 net/core/filter.c:bpf_skb_proto_xlat
   Cyclomatic Complexity 4 net/core/filter.c:bpf_skb_net_shrink
   Cyclomatic Complexity 12 net/core/filter.c:bpf_skb_adjust_net
   Cyclomatic Complexity 4 net/core/filter.c:xdp_do_flush_map
   Cyclomatic Complexity 3 net/core/filter.c:__xdp_map_lookup_elem
   Cyclomatic Complexity 6 net/core/filter.c:__bpf_tx_xdp_map
   Cyclomatic Complexity 12 net/core/filter.c:xdp_do_redirect_map
   Cyclomatic Complexity 4 net/core/filter.c:xdp_do_redirect
   Cyclomatic Complexity 11 net/core/filter.c:bpf_base_func_proto
   Cyclomatic Complexity 4 net/core/filter.c:sk_filter_func_proto
   Cyclomatic Complexity 7 net/core/filter.c:xdp_func_proto
   Cyclomatic Complexity 10 net/core/filter.c:lwt_inout_func_proto
   Cyclomatic Complexity 2 net/core/filter.c:sock_filter_func_proto
   Cyclomatic Complexity 3 net/core/filter.c:sock_ops_func_proto
   Cyclomatic Complexity 9 net/core/filter.c:sk_skb_func_proto
   Cyclomatic Complexity 74 net/core/filter.c:bpf_convert_ctx_access
   Cyclomatic Complexity 5 net/core/filter.c:bpf_get_skb_set_tunnel_proto
   Cyclomatic Complexity 30 net/core/filter.c:tc_cls_act_func_proto
   Cyclomatic Complexity 14 net/core/filter.c:lwt_xmit_func_proto
   Cyclomatic Complexity 4 net/core/filter.c:tc_cls_act_convert_ctx_access
   Cyclomatic Complexity 7 net/core/filter.c:xdp_convert_ctx_access
   Cyclomatic Complexity 14 net/core/filter.c:sock_filter_convert_ctx_access
   Cyclomatic Complexity 27 net/core/filter.c:sock_ops_convert_ctx_access
   Cyclomatic Complexity 1 net/core/filter.c:sk_filter_uncharge
   Cyclomatic Complexity 8 net/core/filter.c:__sk_attach_prog
   Cyclomatic Complexity 3 net/core/filter.c:sk_attach_filter
   Cyclomatic Complexity 6 net/core/filter.c:sk_detach_filter
   Cyclomatic Complexity 2 net/core/filter.c:sk_filter_charge
   Cyclomatic Complexity 3 net/core/filter.c:sk_reuseport_attach_filter
   Cyclomatic Complexity 3 net/core/filter.c:sk_attach_bpf
   Cyclomatic Complexity 3 net/core/filter.c:sk_reuseport_attach_bpf
   Cyclomatic Complexity 2 net/core/filter.c:skb_do_redirect
   Cyclomatic Complexity 2 net/core/filter.c:do_sk_redirect_map
   Cyclomatic Complexity 11 net/core/filter.c:xdp_do_generic_redirect_map
   Cyclomatic Complexity 4 net/core/filter.c:xdp_do_generic_redirect
   Cyclomatic Complexity 14 net/core/filter.c:bpf_helper_changes_pkt_data
   Cyclomatic Complexity 9 net/core/filter.c:sk_get_filter
   Cyclomatic Complexity 1 net/core/filter.c:_GLOBAL__sub_I_65535_0_sk_filter_trim_cap
   In file included from include/linux/bpf_trace.h:5:0,
                    from net/core/filter.c:58:
   net/core/filter.c: In function 'xdp_do_generic_redirect_map':
>> include/trace/events/xdp.h:150:3: warning: 'fwd' may be used uninitialized in this function [-Wmaybe-uninitialized]
      trace_xdp_redirect_map_err(dev, xdp, devmap_ifindex(fwd, map), \
      ^~~~~~~~~~~~~~~~~~~~~~~~~~
   net/core/filter.c:2687:21: note: 'fwd' was declared here
     struct net_device *fwd;
                        ^~~
--
   Cyclomatic Complexity 4 net//core/filter.c:____bpf_skb_set_tunnel_opt
   Cyclomatic Complexity 1 net//core/filter.c:bpf_skb_set_tunnel_opt
   Cyclomatic Complexity 6 net//core/filter.c:____bpf_skb_under_cgroup
   Cyclomatic Complexity 1 net//core/filter.c:bpf_skb_under_cgroup
   Cyclomatic Complexity 3 net//core/filter.c:____bpf_xdp_event_output
   Cyclomatic Complexity 1 net//core/filter.c:bpf_xdp_event_output
   Cyclomatic Complexity 2 net//core/filter.c:____bpf_get_socket_cookie
   Cyclomatic Complexity 1 net//core/filter.c:bpf_get_socket_cookie
   Cyclomatic Complexity 3 net//core/filter.c:____bpf_get_socket_uid
   Cyclomatic Complexity 1 net//core/filter.c:bpf_get_socket_uid
   Cyclomatic Complexity 21 net//core/filter.c:____bpf_setsockopt
   Cyclomatic Complexity 1 net//core/filter.c:bpf_setsockopt
   Cyclomatic Complexity 10 net//core/filter.c:bpf_skb_is_valid_access
   Cyclomatic Complexity 4 net//core/filter.c:sk_filter_is_valid_access
   Cyclomatic Complexity 6 net//core/filter.c:lwt_is_valid_access
   Cyclomatic Complexity 7 net//core/filter.c:sock_filter_is_valid_access
   Cyclomatic Complexity 2 net//core/filter.c:bpf_unclone_prologue
   Cyclomatic Complexity 1 net//core/filter.c:tc_cls_act_prologue
   Cyclomatic Complexity 7 net//core/filter.c:tc_cls_act_is_valid_access
   Cyclomatic Complexity 4 net//core/filter.c:__is_valid_xdp_access
   Cyclomatic Complexity 5 net//core/filter.c:xdp_is_valid_access
   Cyclomatic Complexity 4 net//core/filter.c:__is_valid_sock_ops_access
   Cyclomatic Complexity 3 net//core/filter.c:sock_ops_is_valid_access
   Cyclomatic Complexity 1 net//core/filter.c:sk_skb_prologue
   Cyclomatic Complexity 6 net//core/filter.c:sk_skb_is_valid_access
   Cyclomatic Complexity 3 net//core/filter.c:__xdp_generic_ok_fwd_dev
   Cyclomatic Complexity 11 net//core/filter.c:sk_filter_trim_cap
   Cyclomatic Complexity 3 net//core/filter.c:bpf_skb_copy
   Cyclomatic Complexity 1 net//core/filter.c:bpf_xdp_copy
   Cyclomatic Complexity 2 net//core/filter.c:bpf_skb_grow_rcsum
   Cyclomatic Complexity 2 net//core/filter.c:sk_filter_release
   Cyclomatic Complexity 2 net//core/filter.c:bpf_release_orig_filter
   Cyclomatic Complexity 2 net//core/filter.c:__bpf_prog_release
   Cyclomatic Complexity 1 net//core/filter.c:__sk_filter_release
   Cyclomatic Complexity 2 net//core/filter.c:sk_filter_release_rcu
   Cyclomatic Complexity 1 net//core/filter.c:bpf_prog_destroy
   Cyclomatic Complexity 9 net//core/filter.c:check_load_and_stores
   Cyclomatic Complexity 19 net//core/filter.c:bpf_check_classic
   Cyclomatic Complexity 3 net//core/filter.c:bpf_prog_store_orig_filter
   Cyclomatic Complexity 10 net//core/filter.c:convert_skb_access
   Cyclomatic Complexity 24 net//core/filter.c:convert_bpf_extensions
   Cyclomatic Complexity 52 net//core/filter.c:bpf_convert_filter
   Cyclomatic Complexity 6 net//core/filter.c:bpf_migrate_filter
   Cyclomatic Complexity 5 net//core/filter.c:bpf_prepare_filter
   Cyclomatic Complexity 4 net//core/filter.c:bpf_prog_create
   Cyclomatic Complexity 7 net//core/filter.c:bpf_prog_create_from_user
   Cyclomatic Complexity 6 net//core/filter.c:__get_filter
   Cyclomatic Complexity 5 net//core/filter.c:bpf_warn_invalid_xdp_action
   Cyclomatic Complexity 7 net//core/filter.c:__reuseport_attach_prog
   Cyclomatic Complexity 2 net//core/filter.c:__get_bpf
   Cyclomatic Complexity 3 net//core/filter.c:__bpf_redirect_common
   Cyclomatic Complexity 2 net//core/filter.c:__bpf_redirect
   Cyclomatic Complexity 1 net//core/filter.c:bpf_skb_generic_push
   Cyclomatic Complexity 3 net//core/filter.c:bpf_skb_net_hdr_push
   Cyclomatic Complexity 5 net//core/filter.c:bpf_skb_proto_4_to_6
   Cyclomatic Complexity 4 net//core/filter.c:bpf_skb_net_grow
   Cyclomatic Complexity 2 net//core/filter.c:bpf_skb_generic_pop
   Cyclomatic Complexity 3 net//core/filter.c:bpf_skb_net_hdr_pop
   Cyclomatic Complexity 5 net//core/filter.c:bpf_skb_proto_6_to_4
   Cyclomatic Complexity 3 net//core/filter.c:bpf_skb_proto_xlat
   Cyclomatic Complexity 4 net//core/filter.c:bpf_skb_net_shrink
   Cyclomatic Complexity 12 net//core/filter.c:bpf_skb_adjust_net
   Cyclomatic Complexity 4 net//core/filter.c:xdp_do_flush_map
   Cyclomatic Complexity 3 net//core/filter.c:__xdp_map_lookup_elem
   Cyclomatic Complexity 6 net//core/filter.c:__bpf_tx_xdp_map
   Cyclomatic Complexity 12 net//core/filter.c:xdp_do_redirect_map
   Cyclomatic Complexity 4 net//core/filter.c:xdp_do_redirect
   Cyclomatic Complexity 11 net//core/filter.c:bpf_base_func_proto
   Cyclomatic Complexity 4 net//core/filter.c:sk_filter_func_proto
   Cyclomatic Complexity 7 net//core/filter.c:xdp_func_proto
   Cyclomatic Complexity 10 net//core/filter.c:lwt_inout_func_proto
   Cyclomatic Complexity 2 net//core/filter.c:sock_filter_func_proto
   Cyclomatic Complexity 3 net//core/filter.c:sock_ops_func_proto
   Cyclomatic Complexity 9 net//core/filter.c:sk_skb_func_proto
   Cyclomatic Complexity 74 net//core/filter.c:bpf_convert_ctx_access
   Cyclomatic Complexity 5 net//core/filter.c:bpf_get_skb_set_tunnel_proto
   Cyclomatic Complexity 30 net//core/filter.c:tc_cls_act_func_proto
   Cyclomatic Complexity 14 net//core/filter.c:lwt_xmit_func_proto
   Cyclomatic Complexity 4 net//core/filter.c:tc_cls_act_convert_ctx_access
   Cyclomatic Complexity 7 net//core/filter.c:xdp_convert_ctx_access
   Cyclomatic Complexity 14 net//core/filter.c:sock_filter_convert_ctx_access
   Cyclomatic Complexity 27 net//core/filter.c:sock_ops_convert_ctx_access
   Cyclomatic Complexity 1 net//core/filter.c:sk_filter_uncharge
   Cyclomatic Complexity 8 net//core/filter.c:__sk_attach_prog
   Cyclomatic Complexity 3 net//core/filter.c:sk_attach_filter
   Cyclomatic Complexity 6 net//core/filter.c:sk_detach_filter
   Cyclomatic Complexity 2 net//core/filter.c:sk_filter_charge
   Cyclomatic Complexity 3 net//core/filter.c:sk_reuseport_attach_filter
   Cyclomatic Complexity 3 net//core/filter.c:sk_attach_bpf
   Cyclomatic Complexity 3 net//core/filter.c:sk_reuseport_attach_bpf
   Cyclomatic Complexity 2 net//core/filter.c:skb_do_redirect
   Cyclomatic Complexity 2 net//core/filter.c:do_sk_redirect_map
   Cyclomatic Complexity 11 net//core/filter.c:xdp_do_generic_redirect_map
   Cyclomatic Complexity 4 net//core/filter.c:xdp_do_generic_redirect
   Cyclomatic Complexity 14 net//core/filter.c:bpf_helper_changes_pkt_data
   Cyclomatic Complexity 9 net//core/filter.c:sk_get_filter
   Cyclomatic Complexity 1 net//core/filter.c:_GLOBAL__sub_I_65535_0_sk_filter_trim_cap
   In file included from include/linux/bpf_trace.h:5:0,
                    from net//core/filter.c:58:
   net//core/filter.c: In function 'xdp_do_generic_redirect_map':
>> include/trace/events/xdp.h:150:3: warning: 'fwd' may be used uninitialized in this function [-Wmaybe-uninitialized]
      trace_xdp_redirect_map_err(dev, xdp, devmap_ifindex(fwd, map), \
      ^~~~~~~~~~~~~~~~~~~~~~~~~~
   net//core/filter.c:2687:21: note: 'fwd' was declared here
     struct net_device *fwd;
                        ^~~

vim +/fwd +150 include/trace/events/xdp.h

   138	
   139	#define devmap_ifindex(fwd, map)				\
   140		(!fwd ? 0 :						\
   141		 (!map ? 0 :						\
   142		  ((map->map_type == BPF_MAP_TYPE_DEVMAP) ?		\
   143		   ((struct net_device *)fwd)->ifindex : 0)))
   144	
   145	#define _trace_xdp_redirect_map(dev, xdp, fwd, map, idx)		\
   146		 trace_xdp_redirect_map(dev, xdp, devmap_ifindex(fwd, map),	\
   147					0, map, idx)
   148	
   149	#define _trace_xdp_redirect_map_err(dev, xdp, fwd, map, idx, err)	\
 > 150		 trace_xdp_redirect_map_err(dev, xdp, devmap_ifindex(fwd, map),	\
   151					    err, map, idx)
   152	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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  parent reply	other threads:[~2017-10-06  8:30 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-10-04 12:03 [net-next V4 PATCH 0/5] New bpf cpumap type for XDP_REDIRECT Jesper Dangaard Brouer
2017-10-04 12:03 ` [net-next V4 PATCH 1/5] bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP Jesper Dangaard Brouer
2017-10-04 19:02   ` Alexei Starovoitov
2017-10-05 18:01     ` John Fastabend
2017-10-06  9:03     ` Jesper Dangaard Brouer
2017-10-05  9:40   ` Daniel Borkmann
2017-10-06 10:50     ` Jesper Dangaard Brouer
2017-10-06 14:52       ` Daniel Borkmann
2017-10-06 15:58         ` Jesper Dangaard Brouer
2017-10-25 16:53   ` [bpf] 3ea693a925: BUG:unable_to_handle_kernel kernel test robot
2017-10-25 16:59     ` Michael S. Tsirkin
2017-10-25 10:02       ` [LKP] " Ye Xiaolong
2017-10-25 12:09         ` Ye Xiaolong
2017-10-25 16:54   ` kernel test robot
2017-10-04 12:03 ` [net-next V4 PATCH 2/5] bpf: XDP_REDIRECT enable use of cpumap Jesper Dangaard Brouer
2017-10-05 10:10   ` Daniel Borkmann
2017-10-06 11:17     ` Jesper Dangaard Brouer
2017-10-06 12:01       ` Jesper Dangaard Brouer
2017-10-06 15:45       ` Jesper Dangaard Brouer
2017-10-06  8:30   ` kbuild test robot [this message]
2017-10-04 12:03 ` [net-next V4 PATCH 3/5] bpf: cpumap xdp_buff to skb conversion and allocation Jesper Dangaard Brouer
2017-10-05 10:22   ` Daniel Borkmann
2017-10-06 12:11     ` Jesper Dangaard Brouer
2017-10-04 12:04 ` [net-next V4 PATCH 4/5] bpf: cpumap add tracepoints Jesper Dangaard Brouer
2017-10-04 12:04 ` [net-next V4 PATCH 5/5] samples/bpf: add cpumap sample program xdp_redirect_cpu Jesper Dangaard Brouer

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