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=-17.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham 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 93A0CC433DF for ; Wed, 1 Jul 2020 19:43:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E7C120760 for ; Wed, 1 Jul 2020 19:43:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="lBZgm1P6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726957AbgGATnK (ORCPT ); Wed, 1 Jul 2020 15:43:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726897AbgGATnH (ORCPT ); Wed, 1 Jul 2020 15:43:07 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF19FC08C5C1 for ; Wed, 1 Jul 2020 12:43:07 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id t7so12423830ybk.2 for ; Wed, 01 Jul 2020 12:43:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=X4hxLqM/qKm+bCv7S7D3GJGIZ2XzVLEX41FWfF3jC7c=; b=lBZgm1P6WHJDSgG/2B1vBDRvgbNcbnkZlWRZBHUyr3VrjUGW04XIa2o/If35nV8O6h 8QRkWmkGixC/o0oeE9wNDoJObEtZzKkHqKqc50X2FkNxJWD3yK1aS1jmWYbfItkevgkB m30rn0YBjT6L1lqwa41a58YDIdf+iTtsLACQTFytsMYnsbJ2TOpNRLne4yXrcBND5TV7 BgfZAGOcY2z9bmZfYDMRfd3e69H2qBXzKhxwDnpXl+L0fxsD+elw7kh0n0TcJL4M/Yh5 SXrE7J/usTq1o8tH72Vy2rLrQ5HwQZ0cCEYjQ7J25NsusovwrpyFrgb58tuJImJxo8D0 p3iA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=X4hxLqM/qKm+bCv7S7D3GJGIZ2XzVLEX41FWfF3jC7c=; b=Z395nKLjeZjt8VCq+341AllDNdo5t58gcZwzCHbQgX1eHmZdI9pka4170Q2siXT/0e CuQVYFIwdDgGDWexhvQ7gxpki9hlM6kBZHnsFGk1uwDRcPLJlBbYGO+0GMx9VLMF4SAs YigbIBAC4+HVMsIKmmnmxWzOYQ8X+8s2o/y3A3tktVWSi20ySlteO/SALQyFF/RToztE HA5mBz3scoUNZgy5HlwUNmO0FdDp5qTB/zMg/5TDp43uXR4PDkbB0KjD3LMuDHX6sCWK 7XVr5Lk+O8t131wxVZwQOayfz7WdFB8VIMpAyhIQBO7YQQozdOelilpo3ISYFZ7BTcgQ W/Fg== X-Gm-Message-State: AOAM532n6DQQO64BrFWbgfzTjMWFp/RA29f83Za0Nx9/UuwbNcjGtPL+ aYfcdtsRo5byL5U98CusAho7U+2DAWGwpeQ= X-Google-Smtp-Source: ABdhPJx4d87m+G9jCW0bB6YjMoQXLEXIVwnwPsr0FaSLqU9NkYA5+nCZyE1qZWD470KW1V9UmtvM+HJGV8upo1o= X-Received: by 2002:a25:be02:: with SMTP id h2mr45142945ybk.315.1593632586987; Wed, 01 Jul 2020 12:43:06 -0700 (PDT) Date: Wed, 1 Jul 2020 12:42:57 -0700 In-Reply-To: <20200701194259.3337652-1-saravanak@google.com> Message-Id: <20200701194259.3337652-2-saravanak@google.com> Mime-Version: 1.0 References: <20200701194259.3337652-1-saravanak@google.com> X-Mailer: git-send-email 2.27.0.212.ge8ba1cc988-goog Subject: [PATCH v1 1/3] driver core: Don't do deferred probe in parallel with kernel_init thread From: Saravana Kannan To: Greg Kroah-Hartman , "Rafael J. Wysocki" , Saravana Kannan Cc: linux-kernel@vger.kernel.org, Geert Uytterhoeven , kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The current deferred probe implementation can mess up suspend/resume ordering if deferred probe thread is kicked off in parallel with the main initcall thread (kernel_init thread) [1]. For example: Say device-B is a consumer of device-A. Initcall thread Deferred probe thread =============== ===================== 1. device-A is added. 2. device-B is added. 3. dpm_list is now [device-A, device-B]. 4. driver-A defers probe of device-A. 5. device-A is moved to end of dpm_list 6. dpm_list is now [device-B, device-A] 7. driver-B is registereed and probes device-B. 8. dpm_list stays as [device-B, device-A]. The reverse order of dpm_list is used for suspend. So in this case device-A would incorrectly get suspended before device-B. Commit 716a7a259690 ("driver core: fw_devlink: Add support for batching fwnode parsing") kicked off the deferred probe thread early during boot to run in parallel with the initcall thread and caused suspend/resume regressions. This patch removes the parallel run of the deferred probe thread to avoid the suspend/resume regressions. [1] - https://lore.kernel.org/lkml/CAGETcx8W96KAw-d_siTX4qHB_-7ddk0miYRDQeHE6E0_8qx-6Q@mail.gmail.com/ Fixes: 716a7a259690 ("driver core: fw_devlink: Add support for batching fwnode parsing") Signed-off-by: Saravana Kannan --- drivers/base/base.h | 1 - drivers/base/core.c | 1 - drivers/base/dd.c | 5 ----- 3 files changed, 7 deletions(-) diff --git a/drivers/base/base.h b/drivers/base/base.h index 95c22c0f9036..40fb069a8a7e 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -153,7 +153,6 @@ extern char *make_class_name(const char *name, struct kobject *kobj); extern int devres_release_all(struct device *dev); extern void device_block_probing(void); extern void device_unblock_probing(void); -extern void driver_deferred_probe_force_trigger(void); /* /sys/devices directory */ extern struct kset *devices_kset; diff --git a/drivers/base/core.c b/drivers/base/core.c index 67d39a90b45c..35cc9896eb9e 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1323,7 +1323,6 @@ void fw_devlink_resume(void) goto out; device_link_add_missing_supplier_links(); - driver_deferred_probe_force_trigger(); out: mutex_unlock(&defer_fw_devlink_lock); } diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 9a1d940342ac..48ca81cb8ebc 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -164,11 +164,6 @@ static void driver_deferred_probe_trigger(void) if (!driver_deferred_probe_enable) return; - driver_deferred_probe_force_trigger(); -} - -void driver_deferred_probe_force_trigger(void) -{ /* * A successful probe means that all the devices in the pending list * should be triggered to be reprobed. Move all the deferred devices -- 2.27.0.212.ge8ba1cc988-goog