From patchwork Mon Nov 1 20:03:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qian Cai X-Patchwork-Id: 12597167 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 6BEBBC433EF for ; Mon, 1 Nov 2021 20:04:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53B0460E52 for ; Mon, 1 Nov 2021 20:04:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229966AbhKAUHS (ORCPT ); Mon, 1 Nov 2021 16:07:18 -0400 Received: from alexa-out.qualcomm.com ([129.46.98.28]:25416 "EHLO alexa-out.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229962AbhKAUHQ (ORCPT ); Mon, 1 Nov 2021 16:07:16 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1635797082; x=1667333082; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=WdrwZn4ky8KCT9Yu6bhsOCixKbTKsCZbSgQPCcKL9eg=; b=zOIgKMN4oS5+E2u8AanqHbrE2SABHELr2j0koZzcA62ezIqSEOwhzJa8 cRh0NjVIAN40JSC8mdt22qAMSyO9ERm6HXSpk2zfVYNwSx6tBZrBZCeiR S8HYO/Y6uQYuYvY6hwLNUDAXYeur08IrbBdPHOd7Nkb7HjgtS5G6t3e5d E=; Received: from ironmsg-lv-alpha.qualcomm.com ([10.47.202.13]) by alexa-out.qualcomm.com with ESMTP; 01 Nov 2021 13:04:42 -0700 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg-lv-alpha.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Nov 2021 13:04:41 -0700 Received: from nalasex01a.na.qualcomm.com (10.47.209.196) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.7; Mon, 1 Nov 2021 13:04:41 -0700 Received: from qian-HP-Z2-SFF-G5-Workstation.qualcomm.com (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.7; Mon, 1 Nov 2021 13:04:39 -0700 From: Qian Cai To: "Rafael J. Wysocki" CC: Andy Shevchenko , Heikki Krogerus , Greg Kroah-Hartman , Laurentiu Tudor , , , Qian Cai Subject: [RFC PATCH] software node: Skip duplicated software_node sysfs Date: Mon, 1 Nov 2021 16:03:46 -0400 Message-ID: <20211101200346.16466-1-quic_qiancai@quicinc.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01a.na.qualcomm.com (10.47.209.196) Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org A recent commit allowed device_create_managed_software_node() to call software_node_notify() which could generate duplicated "software_node" sysfs files. For example, "/devices/platform/808622B7:01/xhci-hcd.3.auto/software_node" Since it was created earlier from another path, sysfs_create_link software_node_notify device_add platform_device_add dwc3_host_init dwc3_probe platform_probe really_probe.part.0 really_probe __driver_probe_device driver_probe_device __driver_attach bus_for_each_dev driver_attach bus_add_driver driver_register __platform_driver_register dwc3_driver_init at drivers/usb/dwc3/core.c:2072 do_one_initcall Fixed it by using sysfs_create_link_nowarn() in software_node_notify() to avoid those bad messages during booting, sysfs: cannot create duplicate filename '/devices/platform/808622B7:01/xhci-hcd.3.auto/software_node' Call trace: dump_backtrace show_stack dump_stack_lvl dump_stack sysfs_warn_dup sysfs_do_create_link_sd.isra.0 sysfs_create_link software_node_notify device_create_managed_software_node iort_named_component_init iort_iommu_configure_id acpi_dma_configure_id platform_dma_configure really_probe.part.0 really_probe __driver_probe_device driver_probe_device __driver_attach bus_for_each_dev driver_attach bus_add_driver driver_register __platform_driver_register xhci_plat_init do_one_initcall kernel_init_freeable kernel_init ret_from_fork Fixes: 5aeb05b27f81 ("software node: balance refcount for managed software nodes") Signed-off-by: Qian Cai --- drivers/base/swnode.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c index 4debcea4fb12..0a266c312aa3 100644 --- a/drivers/base/swnode.c +++ b/drivers/base/swnode.c @@ -1126,17 +1126,15 @@ void software_node_notify(struct device *dev) if (!swnode) return; - ret = sysfs_create_link(&dev->kobj, &swnode->kobj, "software_node"); - if (ret) + ret = sysfs_create_link_nowarn(&dev->kobj, &swnode->kobj, + "software_node"); + if (ret && ret != -EEXIST) return; - ret = sysfs_create_link(&swnode->kobj, &dev->kobj, dev_name(dev)); - if (ret) { + if (!sysfs_create_link(&swnode->kobj, &dev->kobj, dev_name(dev))) + kobject_get(&swnode->kobj); + else if (!ret) sysfs_remove_link(&dev->kobj, "software_node"); - return; - } - - kobject_get(&swnode->kobj); } void software_node_notify_remove(struct device *dev)