From patchwork Mon Oct 12 14:19:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lad Prabhakar X-Patchwork-Id: 11832885 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=-9.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MIME_HEADER_CTYPE_ONLY,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, T_TVD_MIME_NO_HEADERS,URIBL_BLOCKED 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 C48A5C433E7 for ; Mon, 12 Oct 2020 14:20:47 +0000 (UTC) Received: from web01.groups.io (web01.groups.io [66.175.222.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 53D742076E for ; Mon, 12 Oct 2020 14:20:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=lists.cip-project.org header.i=@lists.cip-project.org header.b="lyHsY8/i" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 53D742076E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bp.renesas.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=bounce+64572+5545+4520388+8129055@lists.cip-project.org X-Received: by 127.0.0.2 with SMTP id 5TngYY4521723xF55Ur6Wmyy; Mon, 12 Oct 2020 07:20:46 -0700 X-Received: from relmlie6.idc.renesas.com (relmlie6.idc.renesas.com []) by mx.groups.io with SMTP id smtpd.web10.41790.1602512409498286210 for ; Mon, 12 Oct 2020 07:20:13 -0700 X-IronPort-AV: E=Sophos;i="5.77,366,1596466800"; d="scan'208";a="59351935" X-Received: from unknown (HELO relmlir6.idc.renesas.com) ([10.200.68.152]) by relmlie6.idc.renesas.com with ESMTP; 12 Oct 2020 23:20:13 +0900 X-Received: from localhost.localdomain (unknown [10.226.36.204]) by relmlir6.idc.renesas.com (Postfix) with ESMTP id 5A6E540BA087; Mon, 12 Oct 2020 23:20:12 +0900 (JST) From: "Lad Prabhakar" To: cip-dev@lists.cip-project.org, Nobuhiro Iwamatsu , Pavel Machek Cc: Biju Das , Lad Prabhakar Subject: [cip-dev] [RFC PATCH 4.19.y-cip 25/50] PCI: endpoint: Protect concurrent access to pci_epf_ops with mutex Date: Mon, 12 Oct 2020 15:19:08 +0100 Message-Id: <20201012141933.9652-26-prabhakar.mahadev-lad.rj@bp.renesas.com> In-Reply-To: <20201012141933.9652-1-prabhakar.mahadev-lad.rj@bp.renesas.com> References: <20201012141933.9652-1-prabhakar.mahadev-lad.rj@bp.renesas.com> Precedence: Bulk List-Unsubscribe: Sender: cip-dev@lists.cip-project.org List-Id: Mailing-List: list cip-dev@lists.cip-project.org; contact cip-dev+owner@lists.cip-project.org Reply-To: cip-dev@lists.cip-project.org X-Gm-Message-State: Qw4d55ZbPPHFDaa1oCJXKNbWx4520388AA= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.cip-project.org; q=dns/txt; s=20140610; t=1602512446; bh=U7yDFLUlnD9u7nuPfwJXrMB2zU7Bkdy3HznxOPpa4jc=; h=Cc:Content-Type:Date:From:Reply-To:Subject:To; b=lyHsY8/iz1O5nrG3qBdEJ4K5ydvRyCRJyGif9wfBQT/BsqxfGPI2c4j8oULUvxgFg1N 9GFs43lx3o26gEuYPYg/oAjuO1dKtzW5/vi1wdLWzINJf4FrUGS8NMksaJR5njI6Hbp3o kNC0oYaClEhhyn9ut0FbGeFNnzVal7F7f8k= From: Kishon Vijay Abraham I commit 07301c982643a432212840a4b648b5d3f5a061fa upstream. Protect concurrent access to pci_epf_ops with a mutex. Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Lorenzo Pieralisi Signed-off-by: Lad Prabhakar --- drivers/pci/endpoint/pci-epf-core.c | 11 ++++++++++- include/linux/pci-epf.h | 3 +++ 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c index 93f28c65ace0..6e0648991b5c 100644 --- a/drivers/pci/endpoint/pci-epf-core.c +++ b/drivers/pci/endpoint/pci-epf-core.c @@ -35,7 +35,9 @@ void pci_epf_unbind(struct pci_epf *epf) return; } + mutex_lock(&epf->lock); epf->driver->ops->unbind(epf); + mutex_unlock(&epf->lock); module_put(epf->driver->owner); } EXPORT_SYMBOL_GPL(pci_epf_unbind); @@ -49,6 +51,8 @@ EXPORT_SYMBOL_GPL(pci_epf_unbind); */ int pci_epf_bind(struct pci_epf *epf) { + int ret; + if (!epf->driver) { dev_WARN(&epf->dev, "epf device not bound to driver\n"); return -EINVAL; @@ -57,7 +61,11 @@ int pci_epf_bind(struct pci_epf *epf) if (!try_module_get(epf->driver->owner)) return -EAGAIN; - return epf->driver->ops->bind(epf); + mutex_lock(&epf->lock); + ret = epf->driver->ops->bind(epf); + mutex_unlock(&epf->lock); + + return ret; } EXPORT_SYMBOL_GPL(pci_epf_bind); @@ -252,6 +260,7 @@ struct pci_epf *pci_epf_create(const char *name) device_initialize(dev); dev->bus = &pci_epf_bus_type; dev->type = &pci_epf_type; + mutex_init(&epf->lock); ret = dev_set_name(dev, "%s", name); if (ret) { diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h index 4993f7f6439b..bcdf4f07bde7 100644 --- a/include/linux/pci-epf.h +++ b/include/linux/pci-epf.h @@ -110,6 +110,7 @@ struct pci_epf_bar { * @driver: the EPF driver to which this EPF device is bound * @list: to add pci_epf as a list of PCI endpoint functions to pci_epc * @nb: notifier block to notify EPF of any EPC events (like linkup) + * @lock: mutex to protect pci_epf_ops */ struct pci_epf { struct device dev; @@ -124,6 +125,8 @@ struct pci_epf { struct pci_epf_driver *driver; struct list_head list; struct notifier_block nb; + /* mutex to protect against concurrent access of pci_epf_ops */ + struct mutex lock; }; #define to_pci_epf(epf_dev) container_of((epf_dev), struct pci_epf, dev)