From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9913C482DE for ; Tue, 21 Nov 2023 17:40:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="k2nLE0Eh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 05A4AC433C7; Tue, 21 Nov 2023 17:40:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700588403; bh=dFHy5i6PL96RRcxVEbjGSsh0DvPjK5fxlrD6qpb/cIo=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=k2nLE0EhEQLLCVdwgnVMFc2J6pFu9i3/jc+OszvnIcPkh3MEveXDV1VVJpMj7Bj/u v5MVVnBJZb4IsMK2y3Fj7UqLf2dlHhgASe695KQ1yW7XGSrWjmA0hS1Po8O8gHA4MW 5JavES/VmzXpwtcN1ETscczRKMRoe7ejhb4MLTnIDpkjnciCPIvKrxQVY7s3MJHqlr wxqAwGM99eJjR49Fypz0iZAy6ZH10PeHI1tihUwRHJ6Ot9tIPh88orHFK3jGO124mT OjHuU86YfqTCCsbtOjkYms3eakmcmO/vWV4Z/HlN0QvVEs3qztk5ci+lq88tqAA2iE PWMZ4JCbFKtmA== Message-ID: <01240884-fcc9-46d5-ae98-305151112ebc@kernel.org> Date: Tue, 21 Nov 2023 09:40:02 -0800 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: selftest fib_nexthop_multiprefix failed due to route mismatch Content-Language: en-US To: Hangbin Liu Cc: netdev@vger.kernel.org References: From: David Ahern In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/20/23 10:40 PM, Hangbin Liu wrote: > Hi David, > > Recently when run fib_nexthop_multiprefix test I saw all IPv6 test failed. > e.g. > > # ./fib_nexthop_multiprefix.sh > TEST: IPv4: host 0 to host 1, mtu 1300 [ OK ] > TEST: IPv6: host 0 to host 1, mtu 1300 [FAIL] > > With -v it shows > > COMMAND: ip netns exec h0 /usr/sbin/ping6 -s 1350 -c5 -w5 2001:db8:101::1 > PING 2001:db8:101::1(2001:db8:101::1) 1350 data bytes > From 2001:db8:100::64 icmp_seq=1 Packet too big: mtu=1300 > > --- 2001:db8:101::1 ping statistics --- > 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms > > Route get > 2001:db8:101::1 via 2001:db8:100::64 dev eth0 src 2001:db8:100::1 metric 1024 expires 599sec mtu 1300 pref medium > Searching for: > 2001:db8:101::1 from :: via 2001:db8:100::64 dev eth0 src 2001:db8:100::1 .* mtu 1300 > > TEST: IPv6: host 0 to host 1, mtu 1300 [FAIL] > > So we can get the Packet too big from 2001:db8:100::64 successfully. There > is no "from ::" anymore. I plan to fix this issue. But I can't find which > commit changed the behavior and the client could receive Packet too big > message with correct src address. > > Do you have any hints? > > Thanks > Hangbin v6.3.12: $ sudo /mnt/hostshare/fib_nexthop_multiprefix.sh TEST: IPv4: host 0 to host 1, mtu 1300 [ OK ] TEST: IPv6: host 0 to host 1, mtu 1300 [ OK ] TEST: IPv4: host 0 to host 2, mtu 1350 [ OK ] TEST: IPv6: host 0 to host 2, mtu 1350 [ OK ] TEST: IPv4: host 0 to host 3, mtu 1400 [ OK ] TEST: IPv6: host 0 to host 3, mtu 1400 [ OK ] TEST: IPv4: host 0 to host 1, mtu 1300 [ OK ] TEST: IPv6: host 0 to host 1, mtu 1300 [ OK ] TEST: IPv4: host 0 to host 2, mtu 1350 [ OK ] TEST: IPv6: host 0 to host 2, mtu 1350 [ OK ] TEST: IPv4: host 0 to host 3, mtu 1400 [ OK ] TEST: IPv6: host 0 to host 3, mtu 1400 [ OK ] v6.4.13 all passed as well, so it is something recent. I do not have a 6.5 or 6.6 kernels compiled at the moment.