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From:   =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
To:     Peter Zijlstra <peterz@infradead.org>, olsajiri@gmail.com,
        ast@kernel.org, daniel@iogearbox.net
Cc:     linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        bpf@vger.kernel.org, peterz@infradead.org, toke@redhat.com,
        David.Laight@aculab.com, rostedt@goodmis.org
Subject: Re: [PATCH 0/2] bpf: Yet another approach to fix the BPF dispatcher
 thing
In-Reply-To: <20221103120012.717020618@infradead.org>
References: <20221103120012.717020618@infradead.org>
Date:   Thu, 03 Nov 2022 14:42:01 +0100
Message-ID: <875yfwrw7q.fsf@all.your.base.are.belong.to.us>
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Peter Zijlstra <peterz@infradead.org> writes:

> Hi!
>
> Even thought the __attribute__((patchable_function_entry())) solution to =
the
> BPF dispatcher woes works, it turns out to not be supported by the whole =
range
> of ageing compilers we support. Specifically this attribute seems to be G=
CC-8
> and later.
>
> This is another approach -- using static_call() to rewrite the dispatcher
> function. I've compile tested this on:
>
>   x86_64  (inline static-call support)
>   i386    (out-of-line static-call support)
>   aargh64 (no static-call support)
>
> A previous version was tested and found working by Bjorn.
>
> It is split in two patches; first reverting the current approach and then
> introducing the new for ease of review.

Took it for a spin on x86_64/KVM. For the series:

Acked-by: Bj=C3=B6rn T=C3=B6pel <bjorn@kernel.org>
Tested-by: Bj=C3=B6rn T=C3=B6pel <bjorn@kernel.org>