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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 8F80FC48BCF for ; Wed, 9 Jun 2021 15:59:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 796BE60FEB for ; Wed, 9 Jun 2021 15:59:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237163AbhFIQBp (ORCPT ); Wed, 9 Jun 2021 12:01:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59206 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232332AbhFIQBo (ORCPT ); Wed, 9 Jun 2021 12:01:44 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C44FC061574; Wed, 9 Jun 2021 08:59:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=QFACyy0y7HrUHjJ9cPsUOZAld6dTw9TIGvy3FNUUEgI=; b=ez+gR39/yIG6DsvQX0y7KALGqu OMULMPUpfNufKUvUdlEHN9s2LEkIYgMxMfPfQeyQyt1wGMKGeUjcrWNkr7BLGGvaSSV7rC4R0cTtA byA46TmoajpBqD9QCw0smhbVGAyfuECZ9PZXPoFgfdwS4ZDlew+syrpxouv9W9pOhFcEi2ZVOfCpM Zvg1XsScqRW6Vnr1UcQMDERu1VKEejBJYgg0tsaBFC8rNIbU/TJIQvAxrAXuro5+TzC2mFXbiLv0X 89qLCoy/65c33llcaRR67OL30Tz3FXndfAlaBhPMJkPK+YIF5ltu0md10TfhTvsXYyvRXKKutc8Mq +/s34mJA==; Received: from hch by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lr0bt-000fa4-Ku; Wed, 09 Jun 2021 15:59:26 +0000 Date: Wed, 9 Jun 2021 16:59:17 +0100 From: Christoph Hellwig To: Claudio Imbrenda Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org, frankja@linux.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com, david@redhat.com, linux-mm@kvack.org, Andrew Morton , Nicholas Piggin , Uladzislau Rezki , Catalin Marinas , Thomas Gleixner , Ingo Molnar , David Rientjes Subject: Re: [PATCH v2 1/2] mm/vmalloc: export __vmalloc_node_range Message-ID: References: <20210608180618.477766-1-imbrenda@linux.ibm.com> <20210608180618.477766-2-imbrenda@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210608180618.477766-2-imbrenda@linux.ibm.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 08, 2021 at 08:06:17PM +0200, Claudio Imbrenda wrote: > The recent patches to add support for hugepage vmalloc mappings added a > flag for __vmalloc_node_range to allow to request small pages. > This flag is not accessible when calling vmalloc, the only option is to > call directly __vmalloc_node_range, which is not exported. > > This means that a module can't vmalloc memory with small pages. > > Case in point: KVM on s390x needs to vmalloc a large area, and it needs > to be mapped with small pages, because of a hardware limitation. > > This patch exports __vmalloc_node_range so it can be used in modules > too. No. I spent a lot of effort to mak sure such a low-level API is not exported.