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Date:   Fri, 20 May 2022 19:46:51 -0700
From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
To:     Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc:     Greg KH <gregkh@linuxfoundation.org>,
        Jiri Kosina <jikos@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>, Shuah Khan <shuah@kernel.org>,
        Dave Marchevsky <davemarchevsky@fb.com>,
        Joe Stringer <joe@cilium.io>, Jonathan Corbet <corbet@lwn.net>,
        Tero Kristo <tero.kristo@linux.intel.com>,
        linux-kernel@vger.kernel.org, linux-input@vger.kernel.org,
        netdev@vger.kernel.org, bpf@vger.kernel.org,
        linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH bpf-next v5 13/17] HID: bpf: allow to change the report
 descriptor
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References: <20220518205924.399291-1-benjamin.tissoires@redhat.com>
 <20220518205924.399291-14-benjamin.tissoires@redhat.com>
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On Wed, May 18, 2022 at 10:59:20PM +0200, Benjamin Tissoires wrote:
> Add a new tracepoint hid_bpf_rdesc_fixup() so we can trigger a
> report descriptor fixup in the bpf world.
> 
> Whenever the program gets attached/detached, the device is reconnected
> meaning that userspace will see it disappearing and reappearing with
> the new report descriptor.
> 
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
> 
> ---
> 
> changes in v5:
> - adapted for new API
> 
> not in v4
> 
> changes in v3:
> - ensure the ctx.size is properly bounded by allocated size
> - s/link_attached/post_link_attach/
> - removed the switch statement with only one case
> 
> changes in v2:
> - split the series by bpf/libbpf/hid/selftests and samples
> ---
>  drivers/hid/bpf/entrypoints/entrypoints.bpf.c |   6 +
>  .../hid/bpf/entrypoints/entrypoints.lskel.h   | 965 +++++++++---------

Probably add the lskel once in the series to avoid the churn.
It's not reviewable anyway.

>  drivers/hid/bpf/hid_bpf_dispatch.c            |  77 +-
>  drivers/hid/bpf/hid_bpf_dispatch.h            |   1 +
>  drivers/hid/bpf/hid_bpf_jmp_table.c           |   8 +

I'll take a close look at dispatch logic next week.