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=-4.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 9608BC4742C for ; Wed, 11 Nov 2020 10:27:05 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BC98C2075A for ; Wed, 11 Nov 2020 10:27:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="uoNjyA6c" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BC98C2075A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 03B256B006E; Wed, 11 Nov 2020 05:27:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id F063D6B0070; Wed, 11 Nov 2020 05:27:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D7F946B0071; Wed, 11 Nov 2020 05:27:03 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0179.hostedemail.com [216.40.44.179]) by kanga.kvack.org (Postfix) with ESMTP id A8E4B6B006E for ; Wed, 11 Nov 2020 05:27:03 -0500 (EST) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 4814F181AC9CC for ; Wed, 11 Nov 2020 10:27:03 +0000 (UTC) X-FDA: 77471759526.19.crime07_560b283272fd Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin19.hostedemail.com (Postfix) with ESMTP id 27F691AD1B2 for ; Wed, 11 Nov 2020 10:27:03 +0000 (UTC) X-HE-Tag: crime07_560b283272fd X-Filterd-Recvd-Size: 3032 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Wed, 11 Nov 2020 10:27:02 +0000 (UTC) Received: from kernel.org (unknown [77.125.7.142]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5CF2C20756; Wed, 11 Nov 2020 10:26:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605090421; bh=b0ZajuazmUfC3iDVX3AAJzMeBC7oZNbdiuUzj2pr3Cw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=uoNjyA6cs5/wdsvtlaWgvh9dx4BvskHzPCySB2eSBKzLYdj+dChKcciEgPFRAc0pN u6fyzwveY9pzPS2tyq+0JyTjnmNzNgICEsLWsfwmhnljV8qXzJnwkwyvyWedy/MyFB tlN5gwpTalnb4jr47CynpHo6dYoqzbV5zq1oOX0I= Date: Wed, 11 Nov 2020 12:26:54 +0200 From: Mike Rapoport To: Arnd Bergmann Cc: Stefan Agner , Minchan Kim , ngupta@vflare.org, Sergey Senozhatsky , Andrew Morton , sjenning@linux.vnet.ibm.com, gregkh , Arnd Bergmann , Linux-MM , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] mm/zsmalloc: include sparsemem.h for MAX_PHYSMEM_BITS Message-ID: <20201111102654.GF4758@kernel.org> References: <20201108064659.GD301837@kernel.org> <7782fb694a6b0c500e8f32ecf895b2bf@agner.ch> <20201110095806.GH301837@kernel.org> <20201110162155.GA4758@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Nov 11, 2020 at 10:33:29AM +0100, Arnd Bergmann wrote: > On Tue, Nov 10, 2020 at 5:21 PM Mike Rapoport wrote: > > On Tue, Nov 10, 2020 at 12:21:11PM +0100, Arnd Bergmann wrote: > > > > > > To be on the safe side, we could provoke a compile-time error > > > when CONFIG_PHYS_ADDR_T_64BIT is set on a 32-bit > > > architecture, but MAX_POSSIBLE_PHYSMEM_BITS is not set. > > > > Maybe compile time warning and a runtime error in zs_init() if 32 bit > > machine has memory above 4G? > > If the fix is as easy as adding a single line in a header, I think a > compile-time > error makes it easier, no need to wait for someone to boot a broken > system before fixing it. Not sure it would be as easy as adding a single line in a header for MIPS with it's diversity. How about adding a runtime detection like Minchan suggested for !MEMORY_HOTPLUG (e.g. MIPS and ARC) and a compile time error otherwise (i386, ppc)? > Arnd -- Sincerely yours, Mike.