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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99908C433EF for ; Mon, 27 Sep 2021 12:17:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80E2C61058 for ; Mon, 27 Sep 2021 12:17:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234134AbhI0MTS (ORCPT ); Mon, 27 Sep 2021 08:19:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:42766 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234180AbhI0MTN (ORCPT ); Mon, 27 Sep 2021 08:19:13 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 107D761074; Mon, 27 Sep 2021 12:17:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632745055; bh=x4rcTunay/PglYZlssZJEOgWypSVfttpwMB0pa4Pa4Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=shS7LLh4LS9P4/lFpwiiH1KX7ZodCisEjI2hYC5xHzkhdON1Wb7UP6CsM5zM/ywJz gRzkc5YtIv1HtkoW4KIBRwSnVGvHjpK5fOQRDmlCzk8jE+CfjPM8ct3btY66wVOSHq qiFXdCT2w3QZJ92WG3TgcLVk1tJES4x6J5PrrRSY= Date: Mon, 27 Sep 2021 14:17:32 +0200 From: Greg KH To: Laurentiu Tudor Cc: heikki.krogerus@linux.intel.com, jon@solid-run.com, rafael.j.wysocki@intel.com, stable@vger.kernel.org Subject: Re: [PATCH] software node: balance refcount for managed sw nodes Message-ID: References: <20210927102249.12939-1-laurentiu.tudor@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210927102249.12939-1-laurentiu.tudor@nxp.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Sep 27, 2021 at 01:22:49PM +0300, Laurentiu Tudor wrote: > software_node_notify(), on KOBJ_REMOVE drops the refcount twice on managed > software nodes, thus leading to underflow errors. Balance the refcount by > bumping it in the device_create_managed_software_node() function. > > The error [1] was encountered after adding a .shutdown() op to our > fsl-mc-bus driver. > > [Backported to stable from mainline commit > 5aeb05b27f81 ("software node: balance refcount for managed software nodes")] > > [1] > pc : refcount_warn_saturate+0xf8/0x150 > lr : refcount_warn_saturate+0xf8/0x150 > sp : ffff80001009b920 > x29: ffff80001009b920 x28: ffff1a2420318000 x27: 0000000000000000 > x26: ffffccac15e7a038 x25: 0000000000000008 x24: ffffccac168e0030 > x23: ffff1a2428a82000 x22: 0000000000080000 x21: ffff1a24287b5000 > x20: 0000000000000001 x19: ffff1a24261f4400 x18: ffffffffffffffff > x17: 6f72645f726f7272 x16: 0000000000000000 x15: ffff80009009b607 > x14: 0000000000000000 x13: ffffccac16602670 x12: 0000000000000a17 > x11: 000000000000035d x10: ffffccac16602670 x9 : ffffccac16602670 > x8 : 00000000ffffefff x7 : ffffccac1665a670 x6 : ffffccac1665a670 > x5 : 0000000000000000 x4 : 0000000000000000 x3 : 00000000ffffffff > x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff1a2420318000 > Call trace: > refcount_warn_saturate+0xf8/0x150 > kobject_put+0x10c/0x120 > software_node_notify+0xd8/0x140 > device_platform_notify+0x4c/0xb4 > device_del+0x188/0x424 > fsl_mc_device_remove+0x2c/0x4c > rebofind sp.c__fsl_mc_device_remove+0x14/0x2c > device_for_each_child+0x5c/0xac > dprc_remove+0x9c/0xc0 > fsl_mc_driver_remove+0x28/0x64 > __device_release_driver+0x188/0x22c > device_release_driver+0x30/0x50 > bus_remove_device+0x128/0x134 > device_del+0x16c/0x424 > fsl_mc_bus_remove+0x8c/0x114 > fsl_mc_bus_shutdown+0x14/0x20 > platform_shutdown+0x28/0x40 > device_shutdown+0x15c/0x330 > __do_sys_reboot+0x218/0x2a0 > __arm64_sys_reboot+0x28/0x34 > invoke_syscall+0x48/0x114 > el0_svc_common+0x40/0xdc > do_el0_svc+0x2c/0x94 > el0_svc+0x2c/0x54 > el0t_64_sync_handler+0xa8/0x12c > el0t_64_sync+0x198/0x19c > ---[ end trace 32eb1c71c7d86821 ]--- > > Fixes: 151f6ff78cdf ("software node: Provide replacement for device_add_properties()") > Reported-by: Jon Nettleton > Suggested-by: Heikki Krogerus > Reviewed-by: Heikki Krogerus > Signed-off-by: Laurentiu Tudor > Cc: # 5.12+ > --- > drivers/base/swnode.c | 3 +++ > 1 file changed, 3 insertions(+) Next time, please include the git commit id of this patch that is already in Linus's tree so that I don't have to go and manually look it up... thanks, greg k-h