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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 28E28C3A5A2 for ; Thu, 22 Aug 2019 07:59:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E952A21726 for ; Thu, 22 Aug 2019 07:59:51 +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="HUVknUFG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731947AbfHVH7v (ORCPT ); Thu, 22 Aug 2019 03:59:51 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:58902 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731267AbfHVH7t (ORCPT ); Thu, 22 Aug 2019 03:59:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=+paMvfjrV5Cyt2Na5QthK2etUNCHHInfRHmuAwrcRXg=; b=HUVknUFGmxnPC3xhkKvDw2rmF l4o/EMby74fuU8xXgd3F0V1YMzmqwTkZdDtEQ3KiEzcKWZYu9AihjfRGdicwu5/QUW6rowDSQBxLg xW4n+usCDfCdVWn0JmbjIiV/h8aG7LOdOJFu89iz+JLc77g5KlrPkEnkJOT41Fd9nvHH7OdF+Tcmt AilUUmSBH4BNHa8NZhYkDsUBFMZAbwO/xtx3OCKOqq1GEC2kYxfFT0aLTpk2adq3ZkabfOkc8l62i LA1sKd6GPgP58vDupgWvYs0WsUuhaoWkWgpxxFikZ45BotcyZ+d1CSro6QqVCO6Pm+DJ8BMcvFP7i b9NHh6Mfg==; Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1i0i0a-0000bf-6I; Thu, 22 Aug 2019 07:59:48 +0000 Date: Thu, 22 Aug 2019 00:59:48 -0700 From: Christoph Hellwig To: Dave Chinner Cc: linux-xfs@vger.kernel.org, Peter Zijlstra , Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 2/3] xfs: add kmem_alloc_io() Message-ID: <20190822075948.GA31346@infradead.org> References: <20190821083820.11725-1-david@fromorbit.com> <20190821083820.11725-3-david@fromorbit.com> <20190821232440.GB24904@infradead.org> <20190822003131.GR1119@dread.disaster.area> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190822003131.GR1119@dread.disaster.area> User-Agent: Mutt/1.11.4 (2019-03-13) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 22, 2019 at 10:31:32AM +1000, Dave Chinner wrote: > > Btw, I think we should eventually kill off KM_NOFS and just use > > PF_MEMALLOC_NOFS in XFS, as the interface makes so much more sense. > > But that's something for the future. > > Yeah, and it's not quite as simple as just using PF_MEMALLOC_NOFS > at high levels - we'll still need to annotate callers that use KM_NOFS > to avoid lockdep false positives. i.e. any code that can be called from > GFP_KERNEL and reclaim context will throw false positives from > lockdep if we don't annotate tehm correctly.... Oh well. For now we have the XFS kmem_wrappers to turn that into GFP_NOFS so we shouldn't be too worried, but I think that is something we should fix in lockdep to ensure it is generally useful. I've added the maintainers and relevant lists to kick off a discussion.