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 X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT 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 F302FC04E53 for ; Wed, 15 May 2019 11:43:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3BE5206BF for ; Wed, 15 May 2019 11:43:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557920635; bh=vVfQY6gZu/OlDcM6tuuouwA74XHWGJMpGlcOZoThUis=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Yvkb9MZ7Oh5zZ87l5bMQnF31xaX/aFqf1gwZ1PFyVGYCr65MEHHSk+TX3FKLnNZAX Oz9SMUkcBu4goaB/sZX6LFuxCxOQdAaGfdNk0DE6XGP/4+jB4eTQ/KPsk3p5lwxasO 2kJYkqophq6xPe4w8faWgLXUxDuvIrQZQ7pajvCg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732349AbfEOLny (ORCPT ); Wed, 15 May 2019 07:43:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:37960 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731294AbfEOL1G (ORCPT ); Wed, 15 May 2019 07:27:06 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2B4CA20862; Wed, 15 May 2019 11:27:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557919625; bh=vVfQY6gZu/OlDcM6tuuouwA74XHWGJMpGlcOZoThUis=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gqoFVGP7NORUzlFoXlprtjs6Fy1Uqi7iA0eByrEItMC+YsHiEWB7WWBrZ39atPEfj EEK+QAG5jHyYqWRguiuPMsjMhhIFusI/Xxt5czMEBBDdWSpRjf/EL2pYyf0O1CntjJ zX1JsH6mhSq8rhBqjJnBb6vM/B3bfJ59MBE0c/Zk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrea Parri , Tejun Heo Subject: [PATCH 5.0 008/137] kernfs: fix barrier usage in __kernfs_new_node() Date: Wed, 15 May 2019 12:54:49 +0200 Message-Id: <20190515090653.432205540@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190515090651.633556783@linuxfoundation.org> References: <20190515090651.633556783@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrea Parri commit 998267900cee901c5d1dfa029a6304d00acbc29f upstream. smp_mb__before_atomic() can not be applied to atomic_set(). Remove the barrier and rely on RELEASE synchronization. Fixes: ba16b2846a8c6 ("kernfs: add an API to get kernfs node from inode number") Cc: stable@vger.kernel.org Signed-off-by: Andrea Parri Acked-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/kernfs/dir.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -650,11 +650,10 @@ static struct kernfs_node *__kernfs_new_ kn->id.generation = gen; /* - * set ino first. This barrier is paired with atomic_inc_not_zero in + * set ino first. This RELEASE is paired with atomic_inc_not_zero in * kernfs_find_and_get_node_by_ino */ - smp_mb__before_atomic(); - atomic_set(&kn->count, 1); + atomic_set_release(&kn->count, 1); atomic_set(&kn->active, KN_DEACTIVATED_BIAS); RB_CLEAR_NODE(&kn->rb);