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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 42EDAC10F13 for ; Tue, 16 Apr 2019 12:17:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D2E91206BA for ; Tue, 16 Apr 2019 12:17:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amarulasolutions.com header.i=@amarulasolutions.com header.b="rkOpuqbl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728280AbfDPMRV (ORCPT ); Tue, 16 Apr 2019 08:17:21 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:37317 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726241AbfDPMRV (ORCPT ); Tue, 16 Apr 2019 08:17:21 -0400 Received: by mail-wm1-f66.google.com with SMTP id v14so25118499wmf.2 for ; Tue, 16 Apr 2019 05:17:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; h=from:to:cc:subject:date:message-id; bh=7ZNllMz7MPbKT3zJFRifUglXG41JoglLyQCD815xybo=; b=rkOpuqblNViqHK9WKaXeM7eyZbbTG+/47wiv9sZ+6lwWnGUugYwLvwLiJe3g/jerdm qQoz8AZANgdc/ziRNTqDCXutZqOIZ4nF6qMoOoqqtInr8TQq3r4NxhgAenF+wWr38BVX 6mxJWZxCqKN+KeJDMvLGl6o98DptFDfolIBdI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=7ZNllMz7MPbKT3zJFRifUglXG41JoglLyQCD815xybo=; b=iPdm2oVqWnsED8muaAvyBNmz0H3qlB1sION++cK+FhVFqkBzjVa7EsaXOrzEPzhQlp 6NLNPnREtFOLVEEKyorD+Y5FPezjJkn1I1EQalBZrH/d9dDHSwEaZDNF3/KXe3kkAF7u ca4uisQRo+g9MKTQ8ivbHqnNE/Ouw6q1sBaUwsVgSI7k1bXs39+xZzWOWI0nvUzf+Le8 GMfHEVPUF8EimGP+593XAAAa8rY6m2d4J9OiKeCiw1VyG9iMBHkvnolMLcIU2+IzbQIA tI0nhe3dW9pJWi13oPgBNNTpBBGHlAKNLjErZ7lXD5EUlhts0z7bcnJkkiDdO0tZ3SwX VlaQ== X-Gm-Message-State: APjAAAWda+tLzXzjbypUgiX0okPreafMFMULyg5DKy0EcXjUkIfau2ds /2+DEDx6oS96gt79v1FA42DEpg== X-Google-Smtp-Source: APXvYqxwsq0whPkufsZPEYwrbvhSOxQeMvIPpGcziiV0y5GqqNc0zDoEbnNYhMRcoJ5JbS6b1l9fDg== X-Received: by 2002:a7b:cbd6:: with SMTP id n22mr28315308wmi.57.1555417039668; Tue, 16 Apr 2019 05:17:19 -0700 (PDT) Received: from localhost.localdomain (86.100.broadband17.iol.cz. [109.80.100.86]) by smtp.gmail.com with ESMTPSA id 13sm23032823wmf.23.2019.04.16.05.17.18 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 16 Apr 2019 05:17:18 -0700 (PDT) From: Andrea Parri To: Greg Kroah-Hartman , Tejun Heo Cc: linux-kernel@vger.kernel.org Subject: [PATCH] kernfs: fix barrier usage in __kernfs_new_node() Date: Tue, 16 Apr 2019 14:17:11 +0200 Message-Id: <1555417031-27356-1-git-send-email-andrea.parri@amarulasolutions.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- fs/kernfs/dir.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index b84d635567d38..1e7a74b8e0647 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -650,11 +650,10 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root, 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); -- 2.7.4