[Cake] issue with Cake and bpf filter

Pete Heist pete at heistp.net
Sun Aug 12 06:23:05 EDT 2018

One more thing to add to this, when working with another bpf filter which is relatively similar to this simple one (although has some more innocuous looking code like map lookups and read-only operations on the skb) sometimes the attached is suddenly and repeatedly sent to both syslog and kern.log until the disk fills up...

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> On Aug 12, 2018, at 10:17 AM, Pete Heist <pete at heistp.net> wrote:
> I’m seeing a panic (or infinite loop, not sure) when using Cake (not fq_codel or sfq) with a simple bpf filter that just sets skb->tc_classid to a fixed value. I haven’t investigated further yet, but since I’m away from the computer more these days I thought it better to post what I have so far in case someone wants to look at it.
> The attached contains the code and setup script I’m using and a README.txt with instructions on how to reproduce it and some more notes. Be prepared that it’s something I’m doing wrong. :) However, I also probably shouldn’t be able to cause this to happen this easily either, regardless of where the actual issue is...
> Pete
> <simple-bpf.tgz>

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