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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 0336CC433E8 for ; Fri, 17 Jul 2020 09:22:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D27CF20691 for ; Fri, 17 Jul 2020 09:22:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="tZ375G7K" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726629AbgGQJWz (ORCPT ); Fri, 17 Jul 2020 05:22:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53180 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726037AbgGQJWy (ORCPT ); Fri, 17 Jul 2020 05:22:54 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7602CC061755; Fri, 17 Jul 2020 02:22:54 -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=0cWzT9ttoeeT27mu1yXKQJtQPYAF2pim+h1ybnpSsI0=; b=tZ375G7K0Kic3bBHbECJdHyToB uofgKiBUdoGtRF0xWh2CTpH+grA6Ohxha9q/zMVCYJsZ31MyH13ZzHquYmLTMtFkwr1GW1OOiFznY 9UoxGQU4GQIbjTQoPKhd0i+8kmco42C/+8qDBDHOuzLHdfOc/SUOfe/Q0SOs955+k/NuDM7mOfCvp 2EoKAMwVL2rR+PKu16gnz/myd9zqlnSxGPYaSmlZTStTPyMlEysCRoP2w/acV4OYOOuM/HRszIVFj nGIjib9d+s9AkFAR84zQJKNmb+ZLvM196KiL3tpkkG3NYDtuiGcfPF3KXl8/PfVDurMcJrjstthhR FwwipBWA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jwMZn-0007Sc-TL; Fri, 17 Jul 2020 09:22:44 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 759913003D8; Fri, 17 Jul 2020 11:22:43 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 6588829CF6F4C; Fri, 17 Jul 2020 11:22:43 +0200 (CEST) Date: Fri, 17 Jul 2020 11:22:43 +0200 From: Peter Zijlstra To: ira.weiny@intel.com Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , x86@kernel.org, Dave Hansen , Dan Williams , Vishal Verma , Andrew Morton , Fenghua Yu , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH RFC V2 14/17] dax: Stray write protection for dax_direct_access() Message-ID: <20200717092243.GD10769@hirez.programming.kicks-ass.net> References: <20200717072056.73134-1-ira.weiny@intel.com> <20200717072056.73134-15-ira.weiny@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200717072056.73134-15-ira.weiny@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 17, 2020 at 12:20:53AM -0700, ira.weiny@intel.com wrote: > --- a/drivers/dax/super.c > +++ b/drivers/dax/super.c > @@ -30,12 +30,14 @@ static DEFINE_SPINLOCK(dax_host_lock); > > int dax_read_lock(void) > { > + dev_access_enable(); > return srcu_read_lock(&dax_srcu); > } > EXPORT_SYMBOL_GPL(dax_read_lock); > > void dax_read_unlock(int id) > { > + dev_access_disable(); > srcu_read_unlock(&dax_srcu, id); > } > EXPORT_SYMBOL_GPL(dax_read_unlock); This is inconsistently ordered.