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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A3FB2C4332F for ; Wed, 12 Oct 2022 16:19:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229489AbiJLQT5 (ORCPT ); Wed, 12 Oct 2022 12:19:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46604 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229573AbiJLQT4 (ORCPT ); Wed, 12 Oct 2022 12:19:56 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90A791C41D; Wed, 12 Oct 2022 09:19:54 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AAA73B81A61; Wed, 12 Oct 2022 16:19:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E16CCC433D6; Wed, 12 Oct 2022 16:19:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1665591591; bh=TEDjogBy+ecqduxNWQvtcOqrUZbEXN3M1edKYOv2Kik=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vJc+dkG+SDhZ587/nB8yJgEeqLGk6vg6xMvfXgkcwSttnuYcdtUYvKQKGHMFZgGWO OXu5gGm6v3E+Aax24MEzRf58atn8s77BkPUZrhukOLvM80T8F5NmdBeQqjRmJRNYKr lbMVJynC/ibSUrrK4PjJP74170sW9LGV/uP8Lnd4= Date: Wed, 12 Oct 2022 18:20:35 +0200 From: Greg Kroah-Hartman To: Shawn Guo Cc: Jiri Slaby , Martin Kaiser , Pengutronix Kernel Team , NXP Linux Team , linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] serial: imx: Add missing .thaw_noirq hook Message-ID: References: <20221012121353.2346280-1-shawn.guo@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221012121353.2346280-1-shawn.guo@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On Wed, Oct 12, 2022 at 08:13:53PM +0800, Shawn Guo wrote: > The following warning is seen with non-console UART instance when > system hibernates. > > [ 37.371969] ------------[ cut here ]------------ > [ 37.376599] uart3_root_clk already disabled > [ 37.380810] WARNING: CPU: 0 PID: 296 at drivers/clk/clk.c:952 clk_core_disable+0xa4/0xb0 > ... > [ 37.506986] Call trace: > [ 37.509432] clk_core_disable+0xa4/0xb0 > [ 37.513270] clk_disable+0x34/0x50 > [ 37.516672] imx_uart_thaw+0x38/0x5c > [ 37.520250] platform_pm_thaw+0x30/0x6c > [ 37.524089] dpm_run_callback.constprop.0+0x3c/0xd4 > [ 37.528972] device_resume+0x7c/0x160 > [ 37.532633] dpm_resume+0xe8/0x230 > [ 37.536036] hibernation_snapshot+0x288/0x430 > [ 37.540397] hibernate+0x10c/0x2e0 > [ 37.543798] state_store+0xc4/0xd0 > [ 37.547203] kobj_attr_store+0x1c/0x30 > [ 37.550953] sysfs_kf_write+0x48/0x60 > [ 37.554619] kernfs_fop_write_iter+0x118/0x1ac > [ 37.559063] new_sync_write+0xe8/0x184 > [ 37.562812] vfs_write+0x230/0x290 > [ 37.566214] ksys_write+0x68/0xf4 > [ 37.569529] __arm64_sys_write+0x20/0x2c > [ 37.573452] invoke_syscall.constprop.0+0x50/0xf0 > [ 37.578156] do_el0_svc+0x11c/0x150 > [ 37.581648] el0_svc+0x30/0x140 > [ 37.584792] el0t_64_sync_handler+0xe8/0xf0 > [ 37.588976] el0t_64_sync+0x1a0/0x1a4 > [ 37.592639] ---[ end trace 56e22eec54676d75 ]--- > > On hibernating, pm core calls into related hooks in sequence like: > > .freeze > .freeze_noirq > .thaw_noirq > .thaw > > With .thaw_noirq hook being absent, the clock will be disabled in a > unbalanced call which results the warning above. > > imx_uart_freeze() > clk_prepare_enable() > imx_uart_suspend_noirq() > clk_disable() > imx_uart_thaw > clk_disable_unprepare() > > Adding the missing .thaw_noirq hook as imx_uart_resume_noirq() will have > the call sequence corrected as below and thus fix the warning. > > imx_uart_freeze() > clk_prepare_enable() > imx_uart_suspend_noirq() > clk_disable() > imx_uart_resume_noirq() > clk_enable() > imx_uart_thaw > clk_disable_unprepare() > > Signed-off-by: Shawn Guo What commit id does this fix, and does it need to go to older/stable kernels? thanks, greg k-h