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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 A7FCAC433E2 for ; Tue, 1 Sep 2020 17:42:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8C68B2098B for ; Tue, 1 Sep 2020 17:42:30 +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="stdjs9CM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729009AbgIARma (ORCPT ); Tue, 1 Sep 2020 13:42:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728516AbgIARm3 (ORCPT ); Tue, 1 Sep 2020 13:42:29 -0400 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A5E8C061244; Tue, 1 Sep 2020 10:42:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.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=L5+iKG5i9fFPHpLQKtEzdQO5HXzkEnTIXwpxe3If020=; b=stdjs9CM1DFY4aiDaHudhWDJKU s6Hpvn/DWs26Mh7Z8oSw5OtKqQbVdj5SUUKsJ1RzZsqkZ39iCtnmLzLab8+w9xopeoSAKgcoJn6jZ ZUdshd6E0AdA9iKpriv90RAayQNk0C70iq733aVy7W2zU/HsFVzkiBnQAP3pbXRftxhNJfEHVTJ9u UmFULOER0xmaxEZN3kArygBpf/4g90Zo7eLjoRZkwxRpRaG5MPMPil2KZzQTNGZvVKsOilhf4aK+b pMi98ShaxU07nrCWfxpRZlQ+p1FZxTk+EQKLdULpiD/p+qzQGDZ3px05LdXW42p9dOheyfnLt3CAr aL9eBGIg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kDAIU-0000zX-AR; Tue, 01 Sep 2020 17:42:19 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 26867980D85; Tue, 1 Sep 2020 19:42:16 +0200 (CEST) Date: Tue, 1 Sep 2020 19:42:16 +0200 From: Peter Zijlstra To: "Paul E. McKenney" Cc: Lina Iyer , Ulf Hansson , Naresh Kamboju , "Rafael J. Wysocki" , Saravana Kannan , open list , linux-mmc , lkft-triage@lists.linaro.org, rcu@vger.kernel.org, Linux PM , Anders Roxell , Arnd Bergmann , Rajendra Nayak , John Stultz , Stephen Boyd , Lars Povlsen , madhuparnabhowmik10@gmail.com, Viresh Kumar , Vincent Guittot , Thomas Gleixner Subject: Re: WARNING: suspicious RCU usage - sdhci-pltfm: SDHCI platform and OF driver helper Message-ID: <20200901174216.GJ29142@worktop.programming.kicks-ass.net> References: <20200831194402.GD2855@paulmck-ThinkPad-P72> <20200901104206.GU1362448@hirez.programming.kicks-ass.net> <20200901154417.GD20303@codeaurora.org> <20200901155014.GF2674@hirez.programming.kicks-ass.net> <20200901161340.GC29330@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200901161340.GC29330@paulmck-ThinkPad-P72> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org On Tue, Sep 01, 2020 at 09:13:40AM -0700, Paul E. McKenney wrote: > On Tue, Sep 01, 2020 at 05:50:14PM +0200, peterz@infradead.org wrote: > > On Tue, Sep 01, 2020 at 09:44:17AM -0600, Lina Iyer wrote: > > > > > > > > I could add RCU_NONIDLE for the calls to pm_runtime_put_sync_suspend() > > > > > > > > and pm_runtime_get_sync() in psci_enter_domain_idle_state(). Perhaps > > > > > > > > that's the easiest approach, at least to start with. > > > > > I think this would be nice. This should also cover the case, where PM domain > > > power off notification callbacks call trace function internally. Right? > > > > That's just more crap for me to clean up later :-( > > > > trace_*_rcuidle() and RCU_NONIDLE() need to die, not proliferate. > > Moving the idle-entry boundary further in is good in any number of ways. > But experience indicates that no matter how far you move it, there will > be something complex further in. Unless you are pushing it all the way > into all the arch-specific code down as far as it can possibly go? Not all; the simple cpuidle drivers should be good already. The more complicated ones need some help. The patch provided earlier: https://lkml.kernel.org/r/20200901104206.GU1362448@hirez.programming.kicks-ass.net should allow the complicated drivers to take over and DTRT.