netdev - Re: [PATCH bpf 1/2] bpf: avoid races in __bpf_prog

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Date:   Tue, 26 Oct 2021 13:49:41 -0700
From:   Eric Dumazet <edumazet@...gle.com>
To:     Alexei Starovoitov <alexei.starovoitov@...il.com>
Cc:     Eric Dumazet <eric.dumazet@...il.com>,
        Alexei Starovoitov <ast@...nel.org>,
        Daniel Borkmann <daniel@...earbox.net>,
        "David S . Miller" <davem@...emloft.net>,
        netdev <netdev@...r.kernel.org>, bpf <bpf@...r.kernel.org>,
        Andrii Nakryiko <andrii@...nel.org>,
        syzbot <syzkaller@...glegroups.com>
Subject: Re: [PATCH bpf 1/2] bpf: avoid races in __bpf_prog_run() for 32bit arches

On Tue, Oct 26, 2021 at 1:43 PM Alexei Starovoitov
<alexei.starovoitov@...il.com> wrote:
>
> On Tue, Oct 26, 2021 at 1:38 PM Eric Dumazet <eric.dumazet@...il.com> wrote:
> >
> > From: Eric Dumazet <edumazet@...gle.com>
> >
> > __bpf_prog_run() can run from non IRQ contexts, meaning
> > it could be re entered if interrupted.
> >
> > This calls for the irq safe variant of u64_stats_update_{begin|end},
> > or risk a deadlock.
> >
> > This patch is a nop on 64bit arches, fortunately.
>
> u64_stats_update_begin_irqsave is a nop. Good!
> We just sent the last bpf tree PR for this cycle.
> We'll probably take it into bpf-next after CI has a chance to run it.

Great, this means I can add the followup patch to the series.