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 E86CCC433F5 for ; Thu, 30 Sep 2021 05:21:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1528613A7 for ; Thu, 30 Sep 2021 05:21:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348061AbhI3FXW (ORCPT ); Thu, 30 Sep 2021 01:23:22 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:23958 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236162AbhI3FXS (ORCPT ); Thu, 30 Sep 2021 01:23:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1632979296; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ng2IqlAgtnAP4wGSYV5UVVmpXi41Umti5/ShTua3c1I=; b=Qi0+tgKqvhTKEyj0n0+yjqEfohP2wLwi6hD/LqZHdWuBp3klE8tjakcMcaRyaa/loQOnUA odI6gEpWF+R6XYO+mvI48c43zpjTfWWDb2oL4Pz5nk6OucBtxowNr1LeuOXODcuFugBi/4 ltLmIAtkKO+Z1rqAnsVGCIput4b0dZc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-544--8hcRtSdN4u12XoeoN-PQw-1; Thu, 30 Sep 2021 01:21:32 -0400 X-MC-Unique: -8hcRtSdN4u12XoeoN-PQw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9D4981084681; Thu, 30 Sep 2021 05:21:31 +0000 (UTC) Received: from localhost (ovpn-8-17.pek2.redhat.com [10.72.8.17]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2275A6B90C; Thu, 30 Sep 2021 05:21:12 +0000 (UTC) From: Ming Lei To: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, Greg Kroah-Hartman , "Martin K . Petersen" Cc: Changhui Zhong , Yi Zhang , Ming Lei Subject: [PATCH 1/2] driver core: tell caller if the device/kboject is really released Date: Thu, 30 Sep 2021 13:20:27 +0800 Message-Id: <20210930052028.934747-2-ming.lei@redhat.com> In-Reply-To: <20210930052028.934747-1-ming.lei@redhat.com> References: <20210930052028.934747-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Return if the device/kobject is really released to caller. One use case is scsi_device_put() and the scsi device's release handler runs async work to clean up things. We have to piggyback the module_put() into the async work for avoiding to touch unmapped module page. Signed-off-by: Ming Lei --- drivers/base/core.c | 5 +++-- include/linux/device.h | 2 +- include/linux/kobject.h | 2 +- lib/kobject.c | 5 +++-- 4 files changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/base/core.c b/drivers/base/core.c index e65dd803a453..cd1365a934b9 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3459,11 +3459,12 @@ EXPORT_SYMBOL_GPL(get_device); * put_device - decrement reference count. * @dev: device in question. */ -void put_device(struct device *dev) +int put_device(struct device *dev) { /* might_sleep(); */ if (dev) - kobject_put(&dev->kobj); + return kobject_put(&dev->kobj); + return 0; } EXPORT_SYMBOL_GPL(put_device); diff --git a/include/linux/device.h b/include/linux/device.h index e270cb740b9e..ab089d743667 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -949,7 +949,7 @@ extern int (*platform_notify_remove)(struct device *dev); * */ struct device *get_device(struct device *dev); -void put_device(struct device *dev); +int put_device(struct device *dev); bool kill_device(struct device *dev); #ifdef CONFIG_DEVTMPFS diff --git a/include/linux/kobject.h b/include/linux/kobject.h index ea30529fba08..c83cc8a7a170 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -111,7 +111,7 @@ extern int __must_check kobject_move(struct kobject *, struct kobject *); extern struct kobject *kobject_get(struct kobject *kobj); extern struct kobject * __must_check kobject_get_unless_zero( struct kobject *kobj); -extern void kobject_put(struct kobject *kobj); +extern int kobject_put(struct kobject *kobj); extern const void *kobject_namespace(struct kobject *kobj); extern void kobject_get_ownership(struct kobject *kobj, diff --git a/lib/kobject.c b/lib/kobject.c index ea53b30cf483..7ebdd6b99064 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -743,15 +743,16 @@ static void kobject_release(struct kref *kref) * * Decrement the refcount, and if 0, call kobject_cleanup(). */ -void kobject_put(struct kobject *kobj) +int kobject_put(struct kobject *kobj) { if (kobj) { if (!kobj->state_initialized) WARN(1, KERN_WARNING "kobject: '%s' (%p): is not initialized, yet kobject_put() is being called.\n", kobject_name(kobj), kobj); - kref_put(&kobj->kref, kobject_release); + return kref_put(&kobj->kref, kobject_release); } + return 0; } EXPORT_SYMBOL(kobject_put); -- 2.31.1