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=-4.0 required=3.0 tests=BAYES_00,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 4DE3FC433DB for ; Mon, 21 Dec 2020 09:50:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 20C7822CA2 for ; Mon, 21 Dec 2020 09:50:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728534AbgLUJtc (ORCPT ); Mon, 21 Dec 2020 04:49:32 -0500 Received: from mail-oi1-f174.google.com ([209.85.167.174]:38223 "EHLO mail-oi1-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727450AbgLUJtU (ORCPT ); Mon, 21 Dec 2020 04:49:20 -0500 Received: by mail-oi1-f174.google.com with SMTP id x13so10734516oic.5 for ; Mon, 21 Dec 2020 01:49:05 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=/MAEcdhR8xhJxkTH5py9dhvbH9xpgK7YSOJAH3krQv0=; b=dwUuukA9Vuso8nZj5cPex0D3esu/LkjpQe3saBTKGgGIpO0qFdbbaSeOxVn1oQuYAF vwr56vTnoFnt6SpmgQ9yUOfLwBD+TyjXE3NOD3Afxj89CroHFZCbnV5JP/IMKHq8o6un 9PLU8HGkOU7hoJ6Ak9OE64QKslrcBrYdeEU2zWtHKXmNVySnqlK7QE0vBi6qVa2+zAER m/0JhqxgZB24eXgTBEkQYS9bVCGvydbVJgcDkAVaH8a1Th/g0QGzg6vx4eDMvj1DkgGP 6LfvXiWnHB69YAlfOEBq3ZSJ1eQvNK1XrC2vGf3EQLdgeDjuHzSbGhFvY6RG4u4FUCxE 7AoA== X-Gm-Message-State: AOAM533vEDShHYBci+oh7qTpYmaoZycnJgWXUuMoaQ4MfMNP4WV8lfp9 VQr9x4Tq6FBqdgfUAHKkoeeUUS+b8bCWPHvGbYs= X-Google-Smtp-Source: ABdhPJwtNKP2A0sku9Zm77WUohTKFlOtIVVI0H1klrPAdAsp3aLVUYmqK5ZIbNaXK0BAFYy4/iH6ESKscx2Cqx5k93c= X-Received: by 2002:aca:4892:: with SMTP id v140mr10402620oia.71.1608544120040; Mon, 21 Dec 2020 01:48:40 -0800 (PST) MIME-Version: 1.0 References: <20201218031703.3053753-1-saravanak@google.com> In-Reply-To: <20201218031703.3053753-1-saravanak@google.com> From: "Rafael J. Wysocki" Date: Mon, 21 Dec 2020 10:48:23 +0100 Message-ID: Subject: Re: [PATCH v1 0/5] Enable fw_devlink=on by default To: Saravana Kannan Cc: Greg Kroah-Hartman , "Rafael J. Wysocki" , "Cc: Android Kernel" , Linux Kernel Mailing List , Jisheng Zhang , Kevin Hilman , John Stultz , Nicolas Saenz Julienne , Marc Zyngier Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 18, 2020 at 4:17 AM Saravana Kannan wrote: > > As discussed in LPC 2020, cyclic dependencies in firmware that couldn't > be broken using logic was one of the last remaining reasons > fw_devlink=on couldn't be set by default. > > This series changes fw_devlink so that when a cyclic dependency is found > in firmware, the links between those devices fallback to permissive mode > behavior. This way, the rest of the system still benefits from > fw_devlink, but the ambiguous cases fallback to permissive mode. > > Setting fw_devlink=on by default brings a bunch of benefits (currently, > only for systems with device tree firmware): > * Significantly cuts down deferred probes. > * Device probe is effectively attempted in graph order. > * Makes it much easier to load drivers as modules without having to > worry about functional dependencies between modules (depmod is still > needed for symbol dependencies). > > Greg/Rafael, > > Can we get this pulled into 5.11-rc1 or -rc2 soon please? Honestly, I'd rather not (but it's up to Greg). This is a new series posted during the merge window, so it should not be looked at even according to the rules. Personally, I don't have the time to look at it now. > I expect to see some issues due to device drivers that aren't following best > practices (they don't expose the device to driver core). Want to > identify those early on and try to have them fixed before 5.11 release. > See [1] for an example of such a case. So it should be posted right after -rc1 and spend a whole cycle in linux-next. > If we do end up have to revert anything, it'll just be Patch 5/5 (a one > liner). Which totally doesn't matter IMV.