From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14BADC433E6 for ; Mon, 1 Feb 2021 14:19:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD24464EA3 for ; Mon, 1 Feb 2021 14:19:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231145AbhBAOTQ convert rfc822-to-8bit (ORCPT ); Mon, 1 Feb 2021 09:19:16 -0500 Received: from relay12.mail.gandi.net ([217.70.178.232]:59123 "EHLO relay12.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229785AbhBAOTP (ORCPT ); Mon, 1 Feb 2021 09:19:15 -0500 Received: from xps13 (lfbn-tou-1-972-150.w86-210.abo.wanadoo.fr [86.210.203.150]) (Authenticated sender: miquel.raynal@bootlin.com) by relay12.mail.gandi.net (Postfix) with ESMTPSA id 90F55200008; Mon, 1 Feb 2021 14:18:25 +0000 (UTC) Date: Mon, 1 Feb 2021 15:18:24 +0100 From: Miquel Raynal To: Manivannan Sadhasivam Cc: richard@nod.at, vigneshr@ti.com, boris.brezillon@collabora.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, bjorn.andersson@linaro.org Subject: Re: [PATCH] mtd: rawnand: Do not check for bad block if bbt is unavailable Message-ID: <20210201151824.5a9dca4a@xps13> In-Reply-To: <20210130035412.6456-1-manivannan.sadhasivam@linaro.org> References: <20210130035412.6456-1-manivannan.sadhasivam@linaro.org> Organization: Bootlin X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi Manivannan, Manivannan Sadhasivam wrote on Sat, 30 Jan 2021 09:24:12 +0530: > The bbt pointer will be unavailable when NAND_SKIP_BBTSCAN option is > set for a NAND chip. The intention is to skip scanning for the bad > blocks during boot time. I don't have the same understanding: this flag skips the bad block table scan, not the bad block scan. We do want to scan all the devices in order to construct a RAM based table. > However, the MTD core will call > _block_isreserved() and _block_isbad() callbacks unconditionally for > the rawnand devices due to the callbacks always present while collecting > the ecc stats. > > The _block_isreserved() callback for rawnand will bail out if bbt > pointer is not available. But _block_isbad() will continue without > checking for it. So this contradicts with the NAND_SKIP_BBTSCAN option > since the bad block check will happen anyways (ie., not much difference > between scanning for bad blocks and checking each block for bad ones). > > Hence, do not check for the bad block if bbt pointer is unavailable. Not checking for bad blocks at all feels insane. I don't really get the scope and goal of such change? > > Signed-off-by: Manivannan Sadhasivam > --- > drivers/mtd/nand/raw/nand_base.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c > index c33fa1b1847f..f18cd1db79a9 100644 > --- a/drivers/mtd/nand/raw/nand_base.c > +++ b/drivers/mtd/nand/raw/nand_base.c > @@ -4286,6 +4286,9 @@ static int nand_block_isbad(struct mtd_info *mtd, loff_t offs) > int chipnr = (int)(offs >> chip->chip_shift); > int ret; > > + if (!chip->bbt) > + return 0; > + > /* Select the NAND device */ > ret = nand_get_device(chip); > if (ret) Cheers, Miquèl From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4BB0CC433E0 for ; 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x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210201_091831_208771_BDA8451B X-CRM114-Status: GOOD ( 19.52 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: vigneshr@ti.com, richard@nod.at, linux-kernel@vger.kernel.org, bjorn.andersson@linaro.org, boris.brezillon@collabora.com, linux-mtd@lists.infradead.org, linux-arm-msm@vger.kernel.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org SGkgTWFuaXZhbm5hbiwKCk1hbml2YW5uYW4gU2FkaGFzaXZhbSA8bWFuaXZhbm5hbi5zYWRoYXNp dmFtQGxpbmFyby5vcmc+IHdyb3RlIG9uIFNhdCwKMzAgSmFuIDIwMjEgMDk6MjQ6MTIgKzA1MzA6 Cgo+IFRoZSBiYnQgcG9pbnRlciB3aWxsIGJlIHVuYXZhaWxhYmxlIHdoZW4gTkFORF9TS0lQX0JC VFNDQU4gb3B0aW9uIGlzCj4gc2V0IGZvciBhIE5BTkQgY2hpcC4gVGhlIGludGVudGlvbiBpcyB0 byBza2lwIHNjYW5uaW5nIGZvciB0aGUgYmFkCj4gYmxvY2tzIGR1cmluZyBib290IHRpbWUuCgpJ IGRvbid0IGhhdmUgdGhlIHNhbWUgdW5kZXJzdGFuZGluZzogdGhpcyBmbGFnIHNraXBzIHRoZSBi YWQgYmxvY2sKdGFibGUgc2Nhbiwgbm90IHRoZSBiYWQgYmxvY2sgc2Nhbi4gV2UgZG8gd2FudCB0 byBzY2FuIGFsbCB0aGUgZGV2aWNlcwppbiBvcmRlciB0byBjb25zdHJ1Y3QgYSBSQU0gYmFzZWQg dGFibGUuCgo+IEhvd2V2ZXIsIHRoZSBNVEQgY29yZSB3aWxsIGNhbGwKPiBfYmxvY2tfaXNyZXNl cnZlZCgpIGFuZCBfYmxvY2tfaXNiYWQoKSBjYWxsYmFja3MgdW5jb25kaXRpb25hbGx5IGZvcgo+ IHRoZSByYXduYW5kIGRldmljZXMgZHVlIHRvIHRoZSBjYWxsYmFja3MgYWx3YXlzIHByZXNlbnQg d2hpbGUgY29sbGVjdGluZwo+IHRoZSBlY2Mgc3RhdHMuCj4gCj4gVGhlIF9ibG9ja19pc3Jlc2Vy dmVkKCkgY2FsbGJhY2sgZm9yIHJhd25hbmQgd2lsbCBiYWlsIG91dCBpZiBiYnQKPiBwb2ludGVy IGlzIG5vdCBhdmFpbGFibGUuIEJ1dCBfYmxvY2tfaXNiYWQoKSB3aWxsIGNvbnRpbnVlIHdpdGhv dXQKPiBjaGVja2luZyBmb3IgaXQuIFNvIHRoaXMgY29udHJhZGljdHMgd2l0aCB0aGUgTkFORF9T S0lQX0JCVFNDQU4gb3B0aW9uCj4gc2luY2UgdGhlIGJhZCBibG9jayBjaGVjayB3aWxsIGhhcHBl biBhbnl3YXlzIChpZS4sIG5vdCBtdWNoIGRpZmZlcmVuY2UKPiBiZXR3ZWVuIHNjYW5uaW5nIGZv ciBiYWQgYmxvY2tzIGFuZCBjaGVja2luZyBlYWNoIGJsb2NrIGZvciBiYWQgb25lcykuCj4gCj4g SGVuY2UsIGRvIG5vdCBjaGVjayBmb3IgdGhlIGJhZCBibG9jayBpZiBiYnQgcG9pbnRlciBpcyB1 bmF2YWlsYWJsZS4KCk5vdCBjaGVja2luZyBmb3IgYmFkIGJsb2NrcyBhdCBhbGwgZmVlbHMgaW5z YW5lLiBJIGRvbid0IHJlYWxseSBnZXQgdGhlCnNjb3BlIGFuZCBnb2FsIG9mIHN1Y2ggY2hhbmdl PwoKPiAKPiBTaWduZWQtb2ZmLWJ5OiBNYW5pdmFubmFuIFNhZGhhc2l2YW0gPG1hbml2YW5uYW4u c2FkaGFzaXZhbUBsaW5hcm8ub3JnPgo+IC0tLQo+ICBkcml2ZXJzL210ZC9uYW5kL3Jhdy9uYW5k X2Jhc2UuYyB8IDMgKysrCj4gIDEgZmlsZSBjaGFuZ2VkLCAzIGluc2VydGlvbnMoKykKPiAKPiBk aWZmIC0tZ2l0IGEvZHJpdmVycy9tdGQvbmFuZC9yYXcvbmFuZF9iYXNlLmMgYi9kcml2ZXJzL210 ZC9uYW5kL3Jhdy9uYW5kX2Jhc2UuYwo+IGluZGV4IGMzM2ZhMWIxODQ3Zi4uZjE4Y2QxZGI3OWE5 IDEwMDY0NAo+IC0tLSBhL2RyaXZlcnMvbXRkL25hbmQvcmF3L25hbmRfYmFzZS5jCj4gKysrIGIv ZHJpdmVycy9tdGQvbmFuZC9yYXcvbmFuZF9iYXNlLmMKPiBAQCAtNDI4Niw2ICs0Mjg2LDkgQEAg c3RhdGljIGludCBuYW5kX2Jsb2NrX2lzYmFkKHN0cnVjdCBtdGRfaW5mbyAqbXRkLCBsb2ZmX3Qg b2ZmcykKPiAgCWludCBjaGlwbnIgPSAoaW50KShvZmZzID4+IGNoaXAtPmNoaXBfc2hpZnQpOwo+ ICAJaW50IHJldDsKPiAgCj4gKwlpZiAoIWNoaXAtPmJidCkKPiArCQlyZXR1cm4gMDsKPiArCj4g IAkvKiBTZWxlY3QgdGhlIE5BTkQgZGV2aWNlICovCj4gIAlyZXQgPSBuYW5kX2dldF9kZXZpY2Uo Y2hpcCk7Cj4gIAlpZiAocmV0KQoKQ2hlZXJzLApNaXF1w6hsCgpfX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KTGludXggTVREIGRpc2N1c3Npb24g bWFpbGluZyBsaXN0Cmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8v bGludXgtbXRkLwo=