From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [59.151.112.132] (helo=heian.cn.fujitsu.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZTluJ-0001nL-BQ for linux-mtd@lists.infradead.org; Mon, 24 Aug 2015 07:11:04 +0000 Message-ID: <55DAC201.2060909@cn.fujitsu.com> Date: Mon, 24 Aug 2015 15:04:33 +0800 From: Dongsheng Yang MIME-Version: 1.0 To: , , CC: Subject: Re: [PATCH] mkfs.ubifs: remove the check for UBIFS_MAX_LEB_SZ References: <1439873555-5352-1-git-send-email-yangds.fnst@cn.fujitsu.com> <1439887948.31419.118.camel@gmail.com> <55DA6E69.8070301@cn.fujitsu.com> <1440397943.15510.2.camel@gmail.com> <55DABBAC.9040401@cn.fujitsu.com> <1440399957.15510.23.camel@gmail.com> In-Reply-To: <1440399957.15510.23.camel@gmail.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 08/24/2015 03:05 PM, Artem Bityutskiy wrote: > On Mon, 2015-08-24 at 14:37 +0800, Dongsheng Yang wrote: >> On 08/24/2015 02:32 PM, Artem Bityutskiy wrote: >>> On Mon, 2015-08-24 at 09:07 +0800, Dongsheng Yang wrote: >>>> On 08/18/2015 04:52 PM, Artem Bityutskiy wrote: >>>>> On Tue, 2015-08-18 at 12:52 +0800, Dongsheng Yang wrote: >>>>>> There is a commit 92ed6c0 to increase UBIFS_MAX_LEB_SZ >>>>>> to 2MiB. But recently, as the leb size become larger and >>>>>> larger, 2MiB is not a suitable limit any more. >>>>>> >>>>>> Then remove this check in mkfs.ubifs >>>>>> >>>>>> Signed-off-by: Dongsheng Yang >>>>>> --- >>>>>> NOTE: >>>>>> I am not sure the reason why we have to >>>>>> limit the leb size in mkfs.ubifs. Because >>>>>> I did not find any reason for it, I send >>>>>> this patch out. It's very possible I am >>>>>> mising something. >>>>> >>>>> Well, this is sanity check for the user input. If you >>>>> accidentally >>>>> added few zeroes, we want to spot this and inform you, and you >>>>> may >>>>> appreciate that we did not just created a bugus image for you. >>>>> That's >>>>> the idea. >>>> >>>> Sorry, Artem, I was trying to understand it, but I did not got >>>> the >>>> point. Could you give me some more information about the idea? >>>> Maybe >>>> an example? >>> >>> Well, this is defensive programming concept. >> >> Ha, okey, got it. That's good. >> >> But I got a device with ped_size=32M. (Although that would affect >> ubi/ubifs performance negatively, that's another topic) I am >> not sure increasing the MAX_LEB_SIZE to 32M is a good idea, at least >> I don't think it's convincing to others that "I have a device with >> 32M >> peb, so I will increase it to 32M". Could you give me some more >> suggestion? > > Well, defensive programming is just a generally useful concept, it > helps to reveal problems, rather than help them hide. > > But sometimes it stands on your way, in which case you need to relax > the defense. I already suggested to change the constant to the size you > need. I'd appreciate also a comment telling about the system which > needs 32MiB, if possible. Got it. Thanx Yang > > Artem. > . >