On Fri, Oct 06, 2023 at 07:12:15AM -0700, Jakub Kicinski wrote:

On Fri, 6 Oct 2023 15:49:18 +0200 Daniel Borkmann wrote:

quoted

quoted

Which will no longer work with the "pack multiple values into
the reason" scheme of subsys-specific values :(  

Too bad, do you happen to know why it won't work? 

I'm just guessing but the reason is enum skb_drop_reason
and the values of subsystem specific reasons won't be part
of that enum.

Yeah, looks like the subsystem reasons are different enums right?
There's probably a way to still support it in bpftrace but it might take
some minor changes and/or ugly conditionals in scripts.

But I also wonder: why are the subsystem error codes not included into
`enum skb_drop_reason`? It looks like the enum space is partitioned
already. And the modules have already registered themselves into core
kernel (in `enum skb_drop_reason_subsys`). So even if modules are
compiled out there are still hints of it laying around vmlinux.

Thanks,
Daniel

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