From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sven Eckelmann Subject: Re: [B.A.T.M.A.N.] [RFC] batman-adv: always assume 2-byte packet alignment Date: Sat, 03 Feb 2018 09:40:53 +0100 Message-ID: <2600801.iuZaCSQALx@sven-edge> References: <0272f809d25b41fcab4ec5c4b66014f5e341d424.1516792897.git.mschiffer@universe-factory.net> <2157409.R7zQT89qM7@bentobox> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart2284266.5RCCdCvgJg"; micalg="pgp-sha512"; protocol="application/pgp-signature" Cc: netdev@vger.kernel.org, David Miller To: b.a.t.m.a.n@lists.open-mesh.org Return-path: Received: from narfation.org ([79.140.41.39]:60468 "EHLO v3-1039.vlinux.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750725AbeBCIlK (ORCPT ); Sat, 3 Feb 2018 03:41:10 -0500 In-Reply-To: <2157409.R7zQT89qM7@bentobox> Sender: netdev-owner@vger.kernel.org List-ID: --nextPart2284266.5RCCdCvgJg Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" On Mittwoch, 24. Januar 2018 14:40:03 CET Sven Eckelmann wrote: [...] > I know your intentions and I understand the problem. But there is the chance > that David Miller will reject this patch - like he did it some years ago > with a similar (not the same) patch: > > "I'm not applying this, please try work to implement this more > acceptably first." [1] > > But maybe he has now some other opinion because the unaligned problem is > caused by the encapsulation in VXLAN or maybe he has a better idea. At > least VXLAN encap stuff should affect a lot more net code than batman-adv. [...] Looks like we have to assume that David has nothing against the patch and we should get the patch integrated. Affected are any kind of access to the 32 bit values: * &batadv_ogm_packet->seqno * &batadv_ogm2_packet->seqno * &batadv_ogm2_packet->throughput * &batadv_elp_packet->seqno * &batadv_elp_packet->elp_interval * &batadv_icmp_tp_packet->seqno * &batadv_icmp_tp_packet->timestamp * &batadv_tvlv_gateway_data->bandwidth_down * &batadv_tvlv_gateway_data->bandwidth_up * &batadv_tvlv_tt_vlan_data->crc I personally would love to hear that there is a better way to fix this problem. But either this or something like the (out of tree) hacks from OpenWrt [1] seem to be required to work around this problem. Kind regards, Sven [1] https://github.com/openwrt/openwrt/blob/master/target/linux/ar71xx/patches-4.9/910-unaligned_access_hacks.patch --nextPart2284266.5RCCdCvgJg Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part. Content-Transfer-Encoding: 7Bit -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEF10rh2Elc9zjMuACXYcKB8Eme0YFAlp1dZUACgkQXYcKB8Em e0bs8A//YyHrZKnEtqEi3pM61lsIyg0cnwzKSXXYVA/KnQGQBzznjeFYMpUUrhkR s00OyMNXuo+aai4ejpm2MARwL/jYBy9kweSGhJQh74/iUeJe8Xh7U5V9xh0pDxWr NVB+c9pK1S9jxE3dK5BS3ms0cV9vPN1bQ6DulrpfZaighEXFxIRyOEmfTPdb9EhJ fb0luG3v0w96YnHzAZ5O8Efwxr/Jx+/tov1fA6CG9zZUJQEaWIMqXKIE8p9FP6MY 8UpPKPg+ySbD6p9TzJc/0IzQkhw0oTcEyvocPqnQRjwCocpnKOLeLs2ttahDwm3s TOuajppcGYQNXGzd6Sj3YhVK1tBqaH6yc+qRyfrYWWn+8LZ6+Y93iCS1f5y9NVa8 Kn0cY5UvwlYlr9p9mvpukOnpPqTOqKrA+NBwxp9BLVe9v8NAMmwmLbvvH/dt5t8A jXICA0TZI+X+jtGJVDxaE6+zfg5eBzyp0zj4vZMYiygMXteAcNqgFmgrjENzVlpV AjHz7ulJZ7W+zSkQ2Sgztr/NBgCLCw+rgVYnXewVeTCo5dguLiAP+PQirAqwoD8S 3alOhjf5XMfQLh3bhs3a2Yr1vedk/KQsRvLvD9HUK+U5IFbwFAdK9tn2udp3N6Vv +pSzeh2CZ2fjIHYpVa1iHEyTThERgWGL44IM1hoHR/A+xLCWBos= =jb+m -----END PGP SIGNATURE----- --nextPart2284266.5RCCdCvgJg--