From patchwork Mon Feb 15 15:14:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 383135 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 ABE3AC433DB for ; Mon, 15 Feb 2021 15:15:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8937464DA8 for ; Mon, 15 Feb 2021 15:15:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230313AbhBOPP2 (ORCPT ); Mon, 15 Feb 2021 10:15:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230235AbhBOPO4 (ORCPT ); Mon, 15 Feb 2021 10:14:56 -0500 Received: from albert.telenet-ops.be (albert.telenet-ops.be [IPv6:2a02:1800:110:4::f00:1a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E2A1AC061788 for ; Mon, 15 Feb 2021 07:14:10 -0800 (PST) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed60:c5d6:9422:c618:ee58]) by albert.telenet-ops.be with bizsmtp id VTE8240042PLE0706TE84E; Mon, 15 Feb 2021 16:14:09 +0100 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1lBfZf-0079Q4-IO; Mon, 15 Feb 2021 16:14:07 +0100 Received: from geert by rox.of.borg with local (Exim 4.93) (envelope-from ) id 1lBfZe-00AhgE-RK; Mon, 15 Feb 2021 16:14:06 +0100 From: Geert Uytterhoeven To: Greg Kroah-Hartman Cc: Saravana Kannan , Bartosz Golaszewski , "Rafael J . Wysocki" , Kevin Hilman , Ulf Hansson , Magnus Damm , linux-renesas-soc@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH] staging: board: Fix uninitialized spinlock when attaching genpd Date: Mon, 15 Feb 2021 16:14:05 +0100 Message-Id: <20210215151405.2551143-1-geert+renesas@glider.be> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Armadillo-800-EVA with CONFIG_DEBUG_SPINLOCK=y: BUG: spinlock bad magic on CPU#0, swapper/1 lock: lcdc0_device+0x10c/0x308, .magic: 00000000, .owner: /-1, .owner_cpu: 0 CPU: 0 PID: 1 Comm: swapper Not tainted 5.11.0-rc5-armadillo-00036-gbbca04be7a80-dirty #287 Hardware name: Generic R8A7740 (Flattened Device Tree) [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) from [] (do_raw_spin_lock+0x20/0x94) [] (do_raw_spin_lock) from [] (dev_pm_get_subsys_data+0x8c/0x11c) [] (dev_pm_get_subsys_data) from [] (genpd_add_device+0x78/0x2b8) [] (genpd_add_device) from [] (of_genpd_add_device+0x34/0x4c) [] (of_genpd_add_device) from [] (board_staging_register_device+0x11c/0x148) [] (board_staging_register_device) from [] (board_staging_register_devices+0x24/0x28) of_genpd_add_device() is called before platform_device_register(), as it needs to attach the genpd before the device is probed. But the spinlock is only initialized when the device is registered. Fix this by open-coding the spinlock initialization, cfr. device_pm_init_common() in the internal drivers/base code, and in the SuperH early platform code. Signed-off-by: Geert Uytterhoeven --- Exposed by fw_devlinks changing probe order. Masked before due to an unrelated wait context check failure, which disabled any further spinlock checks. https://lore.kernel.org/linux-acpi/CAMuHMdVL-1RKJ5u-HDVA4F4w_+8yGvQQuJQBcZMsdV4yXzzfcw@mail.gmail.com --- drivers/staging/board/board.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/staging/board/board.c b/drivers/staging/board/board.c index cb6feb34dd401ae3..604612937f038e92 100644 --- a/drivers/staging/board/board.c +++ b/drivers/staging/board/board.c @@ -136,6 +136,7 @@ int __init board_staging_register_clock(const struct board_staging_clk *bsc) static int board_staging_add_dev_domain(struct platform_device *pdev, const char *domain) { + struct device *dev = &pdev->dev; struct of_phandle_args pd_args; struct device_node *np; @@ -148,7 +149,11 @@ static int board_staging_add_dev_domain(struct platform_device *pdev, pd_args.np = np; pd_args.args_count = 0; - return of_genpd_add_device(&pd_args, &pdev->dev); + /* Cfr. device_pm_init_common() */ + spin_lock_init(&dev->power.lock); + dev->power.early_init = true; + + return of_genpd_add_device(&pd_args, dev); } #else static inline int board_staging_add_dev_domain(struct platform_device *pdev,