netdev - Re: [PATCH net-next v2 0/7] bpf: get rid of global verifier state and reuse instruction printer

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Date:   Tue, 10 Oct 2017 12:30:37 -0700 (PDT)
From:   David Miller <davem@...emloft.net>
To:     jakub.kicinski@...ronome.com
Cc:     netdev@...r.kernel.org, oss-drivers@...ronome.com,
        alexei.starovoitov@...il.com, daniel@...earbox.net
Subject: Re: [PATCH net-next v2 0/7] bpf: get rid of global verifier state
 and reuse instruction printer

From: Jakub Kicinski <jakub.kicinski@...ronome.com>
Date: Mon,  9 Oct 2017 10:30:08 -0700

> This set started off as simple extraction of eBPF verifier's instruction
> printer into a separate file but evolved into removal of global state.
> The purpose of moving instruction printing code is to be able to reuse it
> from the bpftool.
> 
> As far as the global verifier lock goes, this set removes the global
> variables relating to the log buffer, makes the one-time init done
> by bpf_get_skb_set_tunnel_proto() not depend on any external locking,
> and performs verifier log writeback as data is produced removing the need
> for allocating a potentially large temporary buffer.
> 
> The final step of actually removing the verifier lock is left to someone
> more competent and self-confident :)
> 
> Note that struct bpf_verifier_env is just 40B under two pages now,
> we should probably switch to vzalloc() when it's expanded again...
> 
> v2:
>  - add a selftest;
>  - use env buffer and flush on every print (Alexei);
>  - handle kernel log allocation failures (Daniel);
>  - put the env log members into a struct (Daniel).

Looks great, series applied, thanks Jakub.