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=-3.9 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 B33E8C6369E for ; Sun, 15 Nov 2020 17:32:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FCBA22384 for ; Sun, 15 Nov 2020 17:32:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="MTvsTJZV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727268AbgKORcO (ORCPT ); Sun, 15 Nov 2020 12:32:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49278 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726923AbgKORcO (ORCPT ); Sun, 15 Nov 2020 12:32:14 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1785FC0613D1; Sun, 15 Nov 2020 09:32:14 -0800 (PST) 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=vDL/oO7RpaDTk6A1VW5fgkN8Qlv2jQ1JvN76B37zdfE=; b=MTvsTJZV1uoinRDVag+EO2Jzlf qCdVZ2tFlHK66/+PHeZlNuM4ToJHUnh64v8jGVUk6SnKhXEM/F7/qjJTlW8yFlvIyf9zMxkdIDW6s 33oh08rlPTajsb+MSn/ZQBghwo45AKx4q0KP1/nlNFf3NMSBunMcIcoMt4w0RlZqF4U8sluIg/FMX F+B0oPyXpA+BqZNIFHrFf0dDamNy2fJFxpknJP2mT8uwUWoYjpIk3+ZGeZ29PuK7pRM5TQOGsqrXg t61oNzjl668B0dlpnR6/4unenQjaB+R41sn0zvCfDparG8wAYQVtgv8CdhNw/rXKmXoW72VpEcx6p cnoHr9ZA==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1keLsm-0002fV-4n; Sun, 15 Nov 2020 17:32:08 +0000 Date: Sun, 15 Nov 2020 17:32:08 +0000 From: Matthew Wilcox To: Jarkko Sakkinen Cc: x86@kernel.org, linux-sgx@vger.kernel.org, linux-kernel@vger.kernel.org, Sean Christopherson , linux-mm@kvack.org, Andrew Morton , Mel Gorman , Jethro Beekman , Dave Hansen , andriy.shevchenko@linux.intel.com, asapek@google.com, bp@alien8.de, cedric.xing@intel.com, chenalexchen@google.com, conradparker@google.com, cyhanish@google.com, haitao.huang@intel.com, kai.huang@intel.com, kai.svahn@intel.com, kmoy@google.com, ludloff@google.com, luto@kernel.org, nhorman@redhat.com, npmccallum@redhat.com, puiterwijk@redhat.com, rientjes@google.com, tglx@linutronix.de, yaozhangx@google.com, mikko.ylinen@intel.com Subject: Re: [PATCH v41 10/24] mm: Add 'mprotect' hook to struct vm_operations_struct Message-ID: <20201115173208.GR17076@casper.infradead.org> References: <20201112220135.165028-1-jarkko@kernel.org> <20201112220135.165028-11-jarkko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201112220135.165028-11-jarkko@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 13, 2020 at 12:01:21AM +0200, Jarkko Sakkinen wrote: > +++ b/include/linux/mm.h > @@ -559,6 +559,13 @@ struct vm_operations_struct { > void (*close)(struct vm_area_struct * area); > int (*split)(struct vm_area_struct * area, unsigned long addr); > int (*mremap)(struct vm_area_struct * area); > + /* > + * Called by mprotect() to make driver-specific permission > + * checks before mprotect() is finalised. The VMA must not > + * be modified. Returns 0 if eprotect() can proceed. > + */ This is the wrong place for this documentation, and it's absurdly specific to your implementation. It should be in Documentation/filesystems/locking.rst. > + int (*mprotect)(struct vm_area_struct *vma, unsigned long start, > + unsigned long end, unsigned long newflags); > + > + if (vma->vm_ops && vma->vm_ops->mprotect) > + error = vma->vm_ops->mprotect(vma, nstart, tmp, newflags); > + if (error) > + goto out; > + > error = mprotect_fixup(vma, &prev, nstart, tmp, newflags); > if (error) > goto out; > + > nstart = tmp; Spurious newline added.