From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725808AbgJ2J2D (ORCPT ); Thu, 29 Oct 2020 05:28:03 -0400 Date: Thu, 29 Oct 2020 09:28:00 +0000 From: Christoph Hellwig Subject: Re: [PATCH v4 00/15] follow_pfn and other iomap races Message-ID: <20201029092800.GA494@infradead.org> References: <20201026105818.2585306-1-daniel.vetter@ffwll.ch> <20201029085749.GB25658@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: List-ID: To: Daniel Vetter Cc: Christoph Hellwig , DRI Development , LKML , KVM list , Linux MM , Linux ARM , linux-samsung-soc , "open list:DMA BUFFER SHARING FRAMEWORK" , linux-s390 On Thu, Oct 29, 2020 at 10:25:16AM +0100, Daniel Vetter wrote: > On Thu, Oct 29, 2020 at 9:57 AM Christoph Hellwig wrote: > > > > Maybe I'm missing something, but shouldn't follow_pfn be unexported > > at the end of the series? > > kvm is a legit user and modular afaict. But since you can't use this > without an mmu_notifier anyway (or digging around in pagetable > locking), maybe it should be EXPORT_SYMBOL_GPL now at least? I think it should then take the notifier as an argument even if it isn't diretly used as a safety check, and get a new name describing it. EXPORT_SYMBOL_GPL is probably ok for now, but I'm drafting a new EXPORT_SYMBOL_FOR_MODULE() which will export symbols that can only be used by one specific module, with kvm being a prime user due to all the odd exports it requires that aren't really the kernel interface by any normal means.