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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 CF807C433ED for ; Mon, 19 Apr 2021 16:26:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABBB460725 for ; Mon, 19 Apr 2021 16:26:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238588AbhDSQ1V (ORCPT ); Mon, 19 Apr 2021 12:27:21 -0400 Received: from mx2.suse.de ([195.135.220.15]:47156 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230063AbhDSQ1U (ORCPT ); Mon, 19 Apr 2021 12:27:20 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id C4DD3AF11; Mon, 19 Apr 2021 16:26:49 +0000 (UTC) To: Randy Dunlap , Stephen Rothwell , Linux Next Mailing List Cc: Linux Kernel Mailing List , "linux-block@vger.kernel.org" , linux-bcache@vger.kernel.org, Kent Overstreet References: <20210419202309.0575ad77@canb.auug.org.au> <66d41349-60ba-f27f-5c56-3520a40dd83f@infradead.org> From: Coly Li Subject: Re: linux-next: Tree for Apr 19 (bcache) Message-ID: Date: Tue, 20 Apr 2021 00:26:45 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.9.1 MIME-Version: 1.0 In-Reply-To: <66d41349-60ba-f27f-5c56-3520a40dd83f@infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 4/19/21 11:40 PM, Randy Dunlap wrote: > On 4/19/21 3:23 AM, Stephen Rothwell wrote: >> Hi all, >> >> Changes since 20210416: >> > > on x86_64: > > when > # CONFIG_BLK_DEV is not set > > > WARNING: unmet direct dependencies detected for LIBNVDIMM > Depends on [n]: PHYS_ADDR_T_64BIT [=y] && HAS_IOMEM [=y] && BLK_DEV [=n] > Selected by [y]: > - BCACHE_NVM_PAGES [=y] && MD [=y] && BCACHE [=y] && PHYS_ADDR_T_64BIT [=y] > > > Full randconfig file is attached. > I need hint from kbuild expert. My original idea to use "select LIBNVDIMM" is to avoid the BCACHE_NVM_PAGES option to disappear if LIBNVDIMM is not enabled. Otherwise if nvdimm driver is not configure, users won't know there is a BCACHE_NVM_PAGES option unless they read bcache Kconfig file. But I see nvdimm's Kconfig, it uses "depends on BLK_DEV", I understand it is acceptable that LIBNVDIMM option to disappear from "make menuconfig" if BLK_DEV is not enabled. For such condition, which one is the proper way to set the dependence ? - Change "select LIBNVDIMM" and "select DAX" to "depends on LIBNVDIMM" and "depends on DAX" in bcache Kconfig - Or change "depends on BLK_DEV" to "select BLK_DEV" in nvdimm Kconfig. I want to ask for a proper way to handle such dependence, and I will follow the guide for now and in future. Thanks in advance for the advice. Coly Li