From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.toke.dk (mail.toke.dk [IPv6:2a0c:4d80:42:2001::664]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 3BF393B29D for ; Tue, 3 Nov 2020 06:01:00 -0500 (EST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=toke.dk; s=20161023; t=1604401257; bh=/Lk/s30gedKMSx9yOTu2H1QrZ+9qJuylaecuFFORt2w=; h=From:To:Subject:In-Reply-To:References:Date:From; b=m5v+3cbYewHuZQTe90W2w/lWACq5s5VznEngr6LanlGzCxeU4+n+L//pmIdG7xmnJ IDciDzY3HJSGLB50Mb0YMXbtHjcWczWGfQADY76qmmkq9vHBfYmiZmtVIU3uhrZvy8 IrWG8dfUVe24JqnLFX197j3Mrnp+JFfL1IPG5ny0XnbUOT8wkJpEIIxdUKcwhrxaoV BtzL8RzyQro8/t9I3XrGjKk7lFraLQ3cfba/YuzKyCnM3FfN/9zZtlHff+r1zLuZxD XEVT+z4Bpyv8ceWDcXHylElw8BzOIm38YtDlGXo+ohM5XnMfqZO5C+fvZudvJDg5uI YCg576wVQP8NQ== To: Dean Scarff , cake@lists.bufferbloat.net In-Reply-To: References: <202fa41a446859d714728d90e890d1d2@scarff.id.au> <87d00wkk9f.fsf@toke.dk> Date: Tue, 03 Nov 2020 12:00:55 +0100 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <87k0v2k8m0.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Cake] NLA_F_NESTED is missing X-BeenThere: cake@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Cake - FQ_codel the next generation List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 03 Nov 2020 11:01:00 -0000 Dean Scarff writes: > On Mon, 02 Nov 2020 13:37:00 +0100, Toke wrote: >> Dean Scarff writes: >> >>> Hi, >>> >>> I've been happily running the out-of-tree sch_cake on my Raspberry >>> Pi >>> since 2015. However, I recently upgraded my kernel (to 5.4.72 from >>> Raspbian's raspberrypi-kernel 1.20201022-1), which comes with the >>> sch_cake in mainline. Now, when running: >>> >>> sudo /sbin/tc qdisc add dev ppp0 root cake >>> >>> I get the error: >>> >>> Error: NLA_F_NESTED is missing. >>> >>> I get this error with the sch_cake in mainline, and also with >>> sch_cake >>> built out-of-tree. I also get the error with both Debian's >>> iproute2 >>> 5.9.0-1 (built myself via debian/rules) and "tc" from dtaht's >>> tc-adv >>> repo. >>> >>> Any ideas on what this error means and how to fix it? >> >> I just tried building a 5.4.72 kernel and couldn't reproduce this, so >> it >> seems it's a fault with the raspberry pi kernel; I guess opening a >> bug >> against that would be the way to go? >> >> As for what's actually causing this, I couldn't find anything obvious >> that touches this code in the qdisc layer; but I suppose it has >> something to do with the core qdisc netlink parsing code? >> >> -Toke > > Thanks for the data point. > > For the record, the relevant kernel source is: > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/include/net/netlink.h?h=v5.4.72#n1143 > and the Pi branch: > https://github.com/raspberrypi/linux/blob/raspberrypi-kernel_1.20201022-1/include/net/netlink.h#L1143 > > It seems very unlikely that the Pi folks are patching the netlink > stuff, so I don't think I'll get much traction there unless I can call > out something specifically wrong with their patchset. Well, something odd is certainly going on. The error message you're quoting comes form a part of the netlink parsing code (in the kernel) that shouldn't even be hit by the qdisc addition: NLA_F_NESTED parsing is only enabled in 'strict' validation mode, which is not used for qdiscs. So IDK, maybe a compiler issue or a bit that gets set wrong somewhere? Bisecting the kernel may be the only option here, I don't think you're going to find anything in userspace... -Toke