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[217.229.169.210]) by smtp.gmail.com with ESMTPSA id o3sm23827edq.63.2020.09.24.11.44.21 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 24 Sep 2020 11:44:21 -0700 (PDT) Subject: Re: [RFC PATCH 8/9] surface_aggregator: Add DebugFS interface To: Arnd Bergmann Cc: "linux-kernel@vger.kernel.org" , Greg Kroah-Hartman , =?UTF-8?Q?Bla=c5=be_Hrastn?= =?UTF-8?Q?ik?= , Dorian Stoll References: <20200923151511.3842150-1-luzmaximilian@gmail.com> <20200923151511.3842150-9-luzmaximilian@gmail.com> <5d470a61-bf4d-7ea2-b41f-1163006b1956@gmail.com> From: Maximilian Luz Message-ID: <043f9a77-784d-e887-19e0-57e42ff6bddc@gmail.com> Date: Thu, 24 Sep 2020 20:44:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/24/20 9:41 AM, Arnd Bergmann wrote: > On Thu, Sep 24, 2020 at 12:23 AM Maximilian Luz wrote: >> On 9/23/20 8:51 PM, Arnd Bergmann wrote: >>> On Wed, Sep 23, 2020 at 8:29 PM Maximilian Luz wrote: >>>> On 9/23/20 6:48 PM, Arnd Bergmann wrote: >>> >>> The version I showed avoids the pointers and is compatible with >>> 32-bit user space. >> >> I'm not completely convinced yet that the read/write approach is the way >> I want to do it, especially with Greg suggesting a misc device, but I'll >> keep your solution in mind. > > In case of a character device, I'd go with an ioctl to keep it extensible. > > The read/write based interface is what I'd use in debugfs. Perfect, thanks! I'll follow Greg's suggestion and create a misc device, and then go for the IOCTL interface as you suggest. Thanks again, Max