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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6F907C433EF for ; Wed, 20 Oct 2021 08:54:15 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3458C61183 for ; Wed, 20 Oct 2021 08:54:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 3458C61183 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=QQbVYHqEIzJ+4DDcUcl1YevQmi55jqlphNh/gjhGcQk=; b=FC35cDNis9iYA/ jCVmeler8WNDwKI2tiP1pqh2TjLvr1VzHPXADb57YHjzgJNjKzb587vd2l7OBiA5J8VF9KVRt8XMq GJPbds2nRaYHKLG8fRvv3QsebjaI1q/nQWrC31ONMARjaCNV02xzMLnS+gA9mFCTfxkzuCH34vvUO a+IsJB9Pp2lu3CnegSBhz8f2xh11rdsXO97n4195Smp3YdVu4C5PDr8mCze/50Y37vdNjsSXm4r28 c0Kj+CjDgsgST/+ubRA9kqHYeB6XrS78vzCWT0HSwRB8QEqs3jVBJekwhv4hTTUz10LfCqu2G9SLu jIkv8jkqpewgYCA7meMQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1md7Ls-003tRE-5q; Wed, 20 Oct 2021 08:53:36 +0000 Received: from bhuna.collabora.co.uk ([46.235.227.227]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1md7Lo-003tPQ-Ec for linux-mtd@lists.infradead.org; Wed, 20 Oct 2021 08:53:34 +0000 Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 32EFD1F43F4A; Wed, 20 Oct 2021 09:53:29 +0100 (BST) Date: Wed, 20 Oct 2021 10:53:26 +0200 From: Boris Brezillon To: Sean Nyekjaer Cc: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Boris Brezillon , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/4] mtd: rawnand: nand_bbt: hide suspend/resume hooks while scanning bbt Message-ID: <20211020105326.0dca864a@collabora.com> In-Reply-To: <20211020084534.2472305-2-sean@geanix.com> References: <20211020084534.2472305-1-sean@geanix.com> <20211020084534.2472305-2-sean@geanix.com> Organization: Collabora X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211020_015332_689997_8F4AD57C X-CRM114-Status: GOOD ( 25.75 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Wed, 20 Oct 2021 10:45:31 +0200 Sean Nyekjaer wrote: > From: Boris Brezillon > > The BBT scan logic use the MTD helpers before the MTD layer had a > chance to initialize the device, and that leads to issues when > accessing the uninitialized suspend lock. Let's temporarily set the > suspend/resume hooks to NULL to skip the lock acquire/release step. > > Fixes: 013e6292aaf5 ("mtd: rawnand: Simplify the locking") > Tested-by: Sean Nyekjaer It's missing our Signed-off-by tags. > --- > drivers/mtd/nand/raw/nand_bbt.c | 28 +++++++++++++++++++++++++++- > 1 file changed, 27 insertions(+), 1 deletion(-) > > diff --git a/drivers/mtd/nand/raw/nand_bbt.c b/drivers/mtd/nand/raw/nand_bbt.c > index b7ad030225f8..93d385703469 100644 > --- a/drivers/mtd/nand/raw/nand_bbt.c > +++ b/drivers/mtd/nand/raw/nand_bbt.c > @@ -1397,8 +1397,28 @@ static int nand_create_badblock_pattern(struct nand_chip *this) > */ > int nand_create_bbt(struct nand_chip *this) > { > + struct mtd_info *mtd = nand_to_mtd(this); > + int (*suspend) (struct mtd_info *) = mtd->_suspend; > + void (*resume) (struct mtd_info *) = mtd->_resume; > int ret; > > + /* > + * The BBT scan logic use the MTD helpers before the MTD layer had a > + * chance to initialize the device, and that leads to issues when > + * accessing the uninitialized suspend lock. Let's temporarily set the > + * suspend/resume hooks to NULL to skip the lock acquire/release step. > + * > + * FIXME: This is an ugly hack, so please don't copy this pattern to > + * other MTD implementations. The proper fix would be to implement a > + * generic BBT scan logic at the NAND level that's not using any of the > + * MTD helpers to access pages. We also might consider doing a two > + * step initialization at the MTD level (mtd_device_init() + > + * mtd_device_register()) so some of the fields are initialized > + * early. > + */ > + mtd->_suspend = NULL; > + mtd->_resume = NULL; > + > /* Is a flash based bad block table requested? */ > if (this->bbt_options & NAND_BBT_USE_FLASH) { > /* Use the default pattern descriptors */ > @@ -1422,7 +1442,13 @@ int nand_create_bbt(struct nand_chip *this) > return ret; > } > > - return nand_scan_bbt(this, this->badblock_pattern); > + ret = nand_scan_bbt(this, this->badblock_pattern); > + > + /* Restore the suspend/resume hooks. */ > + mtd->_suspend = suspend; > + mtd->_resume = resume; > + > + return ret; > } > EXPORT_SYMBOL(nand_create_bbt); > ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/