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 413A7C433F5 for ; Mon, 11 Apr 2022 14:17:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347211AbiDKOTp (ORCPT ); Mon, 11 Apr 2022 10:19:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347451AbiDKOSC (ORCPT ); Mon, 11 Apr 2022 10:18:02 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46AEA1116E for ; Mon, 11 Apr 2022 07:15:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=Qyqf1uPVPL3PyVQKl1EmiPuwTiU5LR+HZ4CfCVyTJz8=; b=bPTLtmiIav25Jb/guwqSFV28jI g+lhC3HZR3otZTAAAWozFHObmyxDwt/p/mfL4umlrak2wG9t18Rfh2t+cwKgs4HQ/iXTfXJO0mODZ dXeOnNnr2/WVWZkrvZEwwY4bnWGQw3FYlwjXgePq9gMxAk0ZQnfPaGjD8a3f0X5Xt5iyIoeNxa2t7 s7r3hcJCJs7M04QPJEym6zMfjLvYd/PanwrO+V8A4d8veVWDeQkGi3KjSeCyYzIBCk3oC7hGJZDy/ wl/HnlJ3Agnr1Gf8B34nq1Qfrl2WAi/3PQ2MEnndpaY4FrRZAzjDM81/G99Bc5X8uRYJomuOcJLJD +l5hjY3Q==; Received: from [2001:4bb8:18e:76f5:3747:ef85:d03d:53e4] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1ndupW-009L0x-1k; Mon, 11 Apr 2022 14:15:46 +0000 From: Christoph Hellwig To: Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Zhenyu Wang , Zhi Wang Cc: Jason Gunthorpe , intel-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH 33/34] vfio/mdev: Use the driver core to create the 'remove' file Date: Mon, 11 Apr 2022 16:14:02 +0200 Message-Id: <20220411141403.86980-34-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220411141403.86980-1-hch@lst.de> References: <20220411141403.86980-1-hch@lst.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jason Gunthorpe The device creator is supposed to use the dev.groups value to add sysfs files before device_add is called, not call sysfs_create_files() after device_add() returns. This creates a race with uevent delivery where the extra attribute will not be visible. This was being done because the groups had been co-opted by the mdev driver, now that prior patches have moved the driver's groups to the struct device_driver the dev.group is properly free for use here. Signed-off-by: Jason Gunthorpe Signed-off-by: Christoph Hellwig --- drivers/vfio/mdev/mdev_core.c | 1 + drivers/vfio/mdev/mdev_private.h | 2 ++ drivers/vfio/mdev/mdev_sysfs.c | 19 ++++++++++--------- 3 files changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index 19a20ff420b7f..b8b9e7911e559 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -269,6 +269,7 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid) mdev->dev.parent = parent->dev; mdev->dev.bus = &mdev_bus_type; mdev->dev.release = mdev_device_release; + mdev->dev.groups = mdev_device_groups; mdev->type = type; /* Pairs with the put in mdev_device_release() */ kobject_get(&type->kobj); diff --git a/drivers/vfio/mdev/mdev_private.h b/drivers/vfio/mdev/mdev_private.h index 5a7ffd4e770fd..7c9fc79f3d838 100644 --- a/drivers/vfio/mdev/mdev_private.h +++ b/drivers/vfio/mdev/mdev_private.h @@ -32,6 +32,8 @@ struct mdev_type { unsigned int type_group_id; }; +extern const struct attribute_group *mdev_device_groups[]; + #define to_mdev_type_attr(_attr) \ container_of(_attr, struct mdev_type_attribute, attr) #define to_mdev_type(_kobj) \ diff --git a/drivers/vfio/mdev/mdev_sysfs.c b/drivers/vfio/mdev/mdev_sysfs.c index 5a3873d1a275a..0ccfeb3dda245 100644 --- a/drivers/vfio/mdev/mdev_sysfs.c +++ b/drivers/vfio/mdev/mdev_sysfs.c @@ -244,11 +244,20 @@ static ssize_t remove_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR_WO(remove); -static const struct attribute *mdev_device_attrs[] = { +static struct attribute *mdev_device_attrs[] = { &dev_attr_remove.attr, NULL, }; +static const struct attribute_group mdev_device_group = { + .attrs = mdev_device_attrs, +}; + +const struct attribute_group *mdev_device_groups[] = { + &mdev_device_group, + NULL +}; + int mdev_create_sysfs_files(struct mdev_device *mdev) { struct mdev_type *type = mdev->type; @@ -262,15 +271,8 @@ int mdev_create_sysfs_files(struct mdev_device *mdev) ret = sysfs_create_link(kobj, &type->kobj, "mdev_type"); if (ret) goto type_link_failed; - - ret = sysfs_create_files(kobj, mdev_device_attrs); - if (ret) - goto create_files_failed; - return ret; -create_files_failed: - sysfs_remove_link(kobj, "mdev_type"); type_link_failed: sysfs_remove_link(mdev->type->devices_kobj, dev_name(&mdev->dev)); return ret; @@ -280,7 +282,6 @@ void mdev_remove_sysfs_files(struct mdev_device *mdev) { struct kobject *kobj = &mdev->dev.kobj; - sysfs_remove_files(kobj, mdev_device_attrs); sysfs_remove_link(kobj, "mdev_type"); sysfs_remove_link(mdev->type->devices_kobj, dev_name(&mdev->dev)); } -- 2.30.2