From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27E7AC433F5 for ; Tue, 24 May 2022 20:51:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241757AbiEXUvh (ORCPT ); Tue, 24 May 2022 16:51:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55560 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241768AbiEXUvc (ORCPT ); Tue, 24 May 2022 16:51:32 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 446211C93E for ; Tue, 24 May 2022 13:51:26 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C70316171F for ; Tue, 24 May 2022 20:51:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35D2CC34100; Tue, 24 May 2022 20:51:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1653425485; bh=3eQ2hBlWGUpOpUNaEJFu6V++Da8u1SCVIXJFCtpyb9A=; h=Date:From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=ifSN5L5tItZR9IYTJIwvgBDiIsbIVjNt9LHLdLyNwrBBbmTU4DstIJI9sWZaGlM+r KRRKs2ghOQoL5VnXpiDZJN1+MxG6qt3R6ypZCwGT7rOhJ4yIOBkyVOhCzUX2XKZ7zu XNKBLM7rRmfyB4P9sFnNAFZ4EgmffPAdUZmpANAft6HyYC9gprauHjYs45wOlUiLmw AGEOD4H0QRwXXKQbduXJWfhj6CEW0hxAEUTNfoGr9/l9z42s13KM3NpXdQ3sjD929I 19Oo/5O78W1MPB62pqFWN8bzioDfCDvTE/AvmH2DXogw9Qm0CJc49S0yN1BQCzN0+/ nrHsePNFDQVxA== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id CF6BE5C0A31; Tue, 24 May 2022 13:51:24 -0700 (PDT) Date: Tue, 24 May 2022 13:51:24 -0700 From: "Paul E. McKenney" To: Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= Cc: kernel test robot , kbuild-all@lists.01.org, linux-kernel@vger.kernel.org, Daniel Borkmann Subject: Re: kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression Message-ID: <20220524205124.GS1790663@paulmck-ThinkPad-P17-Gen-1> Reply-To: paulmck@kernel.org References: <202205222029.xpW3PM1y-lkp@intel.com> <87y1yspmmh.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87y1yspmmh.fsf@toke.dk> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 23, 2022 at 12:30:14PM +0200, Toke Høiland-Jørgensen wrote: > kernel test robot writes: > > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > > head: eaea45fc0e7b6ae439526b4a41d91230c8517336 > > commit: 782347b6bcad07ddb574422e01e22c92e05928c8 xdp: Add proper __rcu annotations to redirect map entries > > date: 11 months ago > > config: ia64-randconfig-s031-20220522 (https://download.01.org/0day-ci/archive/20220522/202205222029.xpW3PM1y-lkp@intel.com/config) > > compiler: ia64-linux-gcc (GCC) 11.3.0 > > Hmm, so this is ia64-only? Some kind of macro breakage? Paul, any ideas? Line 1030 looks to me like it is doing everything correctly. I am not sure why sparse would care about the architecture, but perhaps it does. The unrcu_pointer() macro has not changed since March of 2020. All I can suggest is to break that line up to make it easier to figure out exactly what sparse is upset about. Thanx, Paul > -Toke > > > reproduce: > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > > chmod +x ~/bin/make.cross > > # apt-get install sparse > > # sparse version: v0.6.4-dirty > > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=782347b6bcad07ddb574422e01e22c92e05928c8 > > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > > git fetch --no-tags linus master > > git checkout 782347b6bcad07ddb574422e01e22c92e05928c8 > > # save the config file > > mkdir build_dir && cp config build_dir/.config > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=ia64 SHELL=/bin/bash kernel/bpf/ > > > > If you fix the issue, kindly add following tag where applicable > > Reported-by: kernel test robot > > > > > > sparse warnings: (new ones prefixed by >>) > > kernel/bpf/devmap.c:561:29: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct bpf_dtab_netdev *dst @@ got struct bpf_dtab_netdev [noderef] __rcu * @@ > > kernel/bpf/devmap.c:561:29: sparse: expected struct bpf_dtab_netdev *dst > > kernel/bpf/devmap.c:561:29: sparse: got struct bpf_dtab_netdev [noderef] __rcu * > > kernel/bpf/devmap.c:657:29: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct bpf_dtab_netdev *dst @@ got struct bpf_dtab_netdev [noderef] __rcu * @@ > > kernel/bpf/devmap.c:657:29: sparse: expected struct bpf_dtab_netdev *dst > > kernel/bpf/devmap.c:657:29: sparse: got struct bpf_dtab_netdev [noderef] __rcu * > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression > > > > vim +/__rcu +1030 kernel/bpf/devmap.c > > > > 990 > > 991 static int dev_map_notification(struct notifier_block *notifier, > > 992 ulong event, void *ptr) > > 993 { > > 994 struct net_device *netdev = netdev_notifier_info_to_dev(ptr); > > 995 struct bpf_dtab *dtab; > > 996 int i, cpu; > > 997 > > 998 switch (event) { > > 999 case NETDEV_REGISTER: > > 1000 if (!netdev->netdev_ops->ndo_xdp_xmit || netdev->xdp_bulkq) > > 1001 break; > > 1002 > > 1003 /* will be freed in free_netdev() */ > > 1004 netdev->xdp_bulkq = alloc_percpu(struct xdp_dev_bulk_queue); > > 1005 if (!netdev->xdp_bulkq) > > 1006 return NOTIFY_BAD; > > 1007 > > 1008 for_each_possible_cpu(cpu) > > 1009 per_cpu_ptr(netdev->xdp_bulkq, cpu)->dev = netdev; > > 1010 break; > > 1011 case NETDEV_UNREGISTER: > > 1012 /* This rcu_read_lock/unlock pair is needed because > > 1013 * dev_map_list is an RCU list AND to ensure a delete > > 1014 * operation does not free a netdev_map entry while we > > 1015 * are comparing it against the netdev being unregistered. > > 1016 */ > > 1017 rcu_read_lock(); > > 1018 list_for_each_entry_rcu(dtab, &dev_map_list, list) { > > 1019 if (dtab->map.map_type == BPF_MAP_TYPE_DEVMAP_HASH) { > > 1020 dev_map_hash_remove_netdev(dtab, netdev); > > 1021 continue; > > 1022 } > > 1023 > > 1024 for (i = 0; i < dtab->map.max_entries; i++) { > > 1025 struct bpf_dtab_netdev *dev, *odev; > > 1026 > > 1027 dev = rcu_dereference(dtab->netdev_map[i]); > > 1028 if (!dev || netdev != dev->dev) > > 1029 continue; > >> 1030 odev = unrcu_pointer(cmpxchg(&dtab->netdev_map[i], RCU_INITIALIZER(dev), NULL)); > > 1031 if (dev == odev) > > 1032 call_rcu(&dev->rcu, > > 1033 __dev_map_entry_free); > > 1034 } > > 1035 } > > 1036 rcu_read_unlock(); > > 1037 break; > > 1038 default: > > 1039 break; > > 1040 } > > 1041 return NOTIFY_OK; > > 1042 } > > 1043 > > > > -- > > 0-DAY CI Kernel Test Service > > https://01.org/lkp > From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: multipart/mixed; boundary="===============0887155649710479611==" MIME-Version: 1.0 From: Paul E. McKenney To: kbuild-all@lists.01.org Subject: Re: kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address space '__rcu' of expression Date: Tue, 24 May 2022 13:51:24 -0700 Message-ID: <20220524205124.GS1790663@paulmck-ThinkPad-P17-Gen-1> In-Reply-To: <87y1yspmmh.fsf@toke.dk> List-Id: --===============0887155649710479611== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable On Mon, May 23, 2022 at 12:30:14PM +0200, Toke H=C3=B8iland-J=C3=B8rgensen = wrote: > kernel test robot writes: > = > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.= git master > > head: eaea45fc0e7b6ae439526b4a41d91230c8517336 > > commit: 782347b6bcad07ddb574422e01e22c92e05928c8 xdp: Add proper __rcu = annotations to redirect map entries > > date: 11 months ago > > config: ia64-randconfig-s031-20220522 (https://download.01.org/0day-ci/= archive/20220522/202205222029.xpW3PM1y-lkp(a)intel.com/config) > > compiler: ia64-linux-gcc (GCC) 11.3.0 > = > Hmm, so this is ia64-only? Some kind of macro breakage? Paul, any ideas? Line 1030 looks to me like it is doing everything correctly. I am not sure why sparse would care about the architecture, but perhaps it does. The unrcu_pointer() macro has not changed since March of 2020. All I can suggest is to break that line up to make it easier to figure out exactly what sparse is upset about. Thanx, Paul > -Toke > = > > reproduce: > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/s= bin/make.cross -O ~/bin/make.cross > > chmod +x ~/bin/make.cross > > # apt-get install sparse > > # sparse version: v0.6.4-dirty > > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linu= x.git/commit/?id=3D782347b6bcad07ddb574422e01e22c92e05928c8 > > git remote add linus https://git.kernel.org/pub/scm/linux/kerne= l/git/torvalds/linux.git > > git fetch --no-tags linus master > > git checkout 782347b6bcad07ddb574422e01e22c92e05928c8 > > # save the config file > > mkdir build_dir && cp config build_dir/.config > > COMPILER_INSTALL_PATH=3D$HOME/0day COMPILER=3Dgcc-11.3.0 make.c= ross C=3D1 CF=3D'-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=3Dbuild_dir ARCH= =3Dia64 SHELL=3D/bin/bash kernel/bpf/ > > > > If you fix the issue, kindly add following tag where applicable > > Reported-by: kernel test robot > > > > > > sparse warnings: (new ones prefixed by >>) > > kernel/bpf/devmap.c:561:29: sparse: sparse: incorrect type in assign= ment (different address spaces) @@ expected struct bpf_dtab_netdev *dst= @@ got struct bpf_dtab_netdev [noderef] __rcu * @@ > > kernel/bpf/devmap.c:561:29: sparse: expected struct bpf_dtab_net= dev *dst > > kernel/bpf/devmap.c:561:29: sparse: got struct bpf_dtab_netdev [= noderef] __rcu * > > kernel/bpf/devmap.c:657:29: sparse: sparse: incorrect type in assign= ment (different address spaces) @@ expected struct bpf_dtab_netdev *dst= @@ got struct bpf_dtab_netdev [noderef] __rcu * @@ > > kernel/bpf/devmap.c:657:29: sparse: expected struct bpf_dtab_net= dev *dst > > kernel/bpf/devmap.c:657:29: sparse: got struct bpf_dtab_netdev [= noderef] __rcu * > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > >>> kernel/bpf/devmap.c:1030:40: sparse: sparse: cast removes address spa= ce '__rcu' of expression > > > > vim +/__rcu +1030 kernel/bpf/devmap.c > > > > 990 = > > 991 static int dev_map_notification(struct notifier_block *notifier, > > 992 ulong event, void *ptr) > > 993 { > > 994 struct net_device *netdev =3D netdev_notifier_info_to_dev(ptr); > > 995 struct bpf_dtab *dtab; > > 996 int i, cpu; > > 997 = > > 998 switch (event) { > > 999 case NETDEV_REGISTER: > > 1000 if (!netdev->netdev_ops->ndo_xdp_xmit || netdev->xdp_bulkq) > > 1001 break; > > 1002 = > > 1003 /* will be freed in free_netdev() */ > > 1004 netdev->xdp_bulkq =3D alloc_percpu(struct xdp_dev_bulk_queue); > > 1005 if (!netdev->xdp_bulkq) > > 1006 return NOTIFY_BAD; > > 1007 = > > 1008 for_each_possible_cpu(cpu) > > 1009 per_cpu_ptr(netdev->xdp_bulkq, cpu)->dev =3D netdev; > > 1010 break; > > 1011 case NETDEV_UNREGISTER: > > 1012 /* This rcu_read_lock/unlock pair is needed because > > 1013 * dev_map_list is an RCU list AND to ensure a delete > > 1014 * operation does not free a netdev_map entry while we > > 1015 * are comparing it against the netdev being unregistered. > > 1016 */ > > 1017 rcu_read_lock(); > > 1018 list_for_each_entry_rcu(dtab, &dev_map_list, list) { > > 1019 if (dtab->map.map_type =3D=3D BPF_MAP_TYPE_DEVMAP_HASH) { > > 1020 dev_map_hash_remove_netdev(dtab, netdev); > > 1021 continue; > > 1022 } > > 1023 = > > 1024 for (i =3D 0; i < dtab->map.max_entries; i++) { > > 1025 struct bpf_dtab_netdev *dev, *odev; > > 1026 = > > 1027 dev =3D rcu_dereference(dtab->netdev_map[i]); > > 1028 if (!dev || netdev !=3D dev->dev) > > 1029 continue; > >> 1030 odev =3D unrcu_pointer(cmpxchg(&dtab->netdev_map[i], RCU_INIT= IALIZER(dev), NULL)); > > 1031 if (dev =3D=3D odev) > > 1032 call_rcu(&dev->rcu, > > 1033 __dev_map_entry_free); > > 1034 } > > 1035 } > > 1036 rcu_read_unlock(); > > 1037 break; > > 1038 default: > > 1039 break; > > 1040 } > > 1041 return NOTIFY_OK; > > 1042 } > > 1043 = > > > > -- = > > 0-DAY CI Kernel Test Service > > https://01.org/lkp >=20 --===============0887155649710479611==--