Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
Date:   Fri, 4 Mar 2022 19:32:26 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc:     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>,
        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
Subject: Re: [PATCH bpf-next v2 07/28] bpf/hid: add a new attach type to
 change the report descriptor
Message-ID: <YiJbOu8NY9UhigKZ@kroah.com>
References: <20220304172852.274126-1-benjamin.tissoires@redhat.com>
 <20220304172852.274126-8-benjamin.tissoires@redhat.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20220304172852.274126-8-benjamin.tissoires@redhat.com>
Precedence: bulk

On Fri, Mar 04, 2022 at 06:28:31PM +0100, Benjamin Tissoires wrote:
> The report descriptor is the dictionary of the HID protocol specific
> to the given device.
> Changing it is a common habit in the HID world, and making that feature
> accessible from eBPF allows to fix devices without having to install a
> new kernel.
> 
> However, the report descriptor is supposed to be static on a device.
> To be able to change it, we need to reconnect the device at the HID
> level.
> So whenever the report descriptor program type is attached or detached,
> we call on a hook on HID to notify it that there is something to be
> done.
> 
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>