From patchwork Tue Jul 2 08:02:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 168297 Delivered-To: patch@linaro.org Received: by 2002:a92:4782:0:0:0:0:0 with SMTP id e2csp3941497ilk; Tue, 2 Jul 2019 01:15:49 -0700 (PDT) X-Google-Smtp-Source: APXvYqw6/lk30phLoxQVW73/jk25srPyxeVW/WYB9LxnGygfVi9qbpXQi7KQ/ir3SAF5KhfHrcOv X-Received: by 2002:a17:90a:9201:: with SMTP id m1mr4188250pjo.38.1562055349811; Tue, 02 Jul 2019 01:15:49 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1562055349; cv=none; d=google.com; s=arc-20160816; b=c/kVFH0sYg+t36l00DefuWYA5g48QFPZDVqqcM7l+cUuLuxDu/JqzKpwp5vlF2NBaN RqL3bYwk0FydlkyKg0w30NMXsaqcbWK9cKEHVMJkOH9iMXIyKJsWDYxalFlMh7eEHknp RyCl2j1Asi44rICluLIUIAbf4efLMmUcZeBtDJJ6UG+cM/uqklE4DgQyMjj4CKZYnRmG MQdHARAezusdFt8pDczCR7Ykx6lqAPwba98IiCAsPhRM6YqU+xrowKph+4F2Bj6aGxgd 8c7DokhICbmiHF1WqDRHNKaeXABXVzWL3ZoQxnp/lXQPZpe4M3kjJPafLbrAZVi3YLul oiHQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=MgKBYedVmlJkYlgCCJHST89UjJ2AR1SUH+TA30bu/qQ=; b=dVLY/E6HoB+dEz9mx482vGi4kWBkzs1j1FHmdtbj9o3x2v9eIC4vmKtQ83d6Od6xqo phnfVqy17HRtcMURMyiHXf05o1o18WZPaNCy89VBUPuHwX8gy9GGcSrSMKyiCw6uZni7 ASGFX+zHze6gt3wmNLiYuNUH7RCf2h71RXDC/t7HX9jI+eumv1tyA/f+z7pTUQ8v45gx s/D/puMNKUBfizMNrAUR2yKF+vpnF9AWy5VwwMskwC9T4qGO8hJq2tnzdbMYfSQnnGsq 3owR/QaC7YwAxJJykyyLHWunNX6pMi0gNroAXRHiU3g3bg10QJUnhQLe0D9DwFEkTse/ vvlA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=iZ26Fpzo; spf=pass (google.com: best guess record for domain of stable-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id d5si12397844pla.17.2019.07.02.01.15.49; Tue, 02 Jul 2019 01:15:49 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of stable-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=iZ26Fpzo; spf=pass (google.com: best guess record for domain of stable-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727373AbfGBIPs (ORCPT + 14 others); Tue, 2 Jul 2019 04:15:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:50088 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727756AbfGBIEe (ORCPT ); Tue, 2 Jul 2019 04:04:34 -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 1B8E821479; Tue, 2 Jul 2019 08:04:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562054673; bh=FHZuVNPHrPEskjr4ytkC96O85qWn+vClIozAy1WdJBk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iZ26FpzoJ8rdCzkCD0stE3YIMp+X90hdY6AyzJFxIHvL6tklWPbOvYAp37cQgvozx P4JSfbRz2WgWebmzhVqmfGmb3lnWdwX86RwiSyyaH2vuYyIUuPRKGuYakpgKC32HfP wj8aZCOc3x5X7xtV7VwkLn59PHR7NU3EP3AQ6n74= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Will Deacon Subject: [PATCH 5.1 52/55] futex: Update comments and docs about return values of arch futex code Date: Tue, 2 Jul 2019 10:02:00 +0200 Message-Id: <20190702080126.770004015@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190702080124.103022729@linuxfoundation.org> References: <20190702080124.103022729@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Will Deacon commit 427503519739e779c0db8afe876c1b33f3ac60ae upstream. The architecture implementations of 'arch_futex_atomic_op_inuser()' and 'futex_atomic_cmpxchg_inatomic()' are permitted to return only -EFAULT, -EAGAIN or -ENOSYS in the case of failure. Update the comments in the asm-generic/ implementation and also a stray reference in the robust futex documentation. Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman --- Documentation/robust-futexes.txt | 3 +-- include/asm-generic/futex.h | 8 ++++++-- 2 files changed, 7 insertions(+), 4 deletions(-) --- a/Documentation/robust-futexes.txt +++ b/Documentation/robust-futexes.txt @@ -218,5 +218,4 @@ All other architectures should build jus the new syscalls yet. Architectures need to implement the new futex_atomic_cmpxchg_inatomic() -inline function before writing up the syscalls (that function returns --ENOSYS right now). +inline function before writing up the syscalls. --- a/include/asm-generic/futex.h +++ b/include/asm-generic/futex.h @@ -23,7 +23,9 @@ * * Return: * 0 - On success - * <0 - On error + * -EFAULT - User access resulted in a page fault + * -EAGAIN - Atomic operation was unable to complete due to contention + * -ENOSYS - Operation not supported */ static inline int arch_futex_atomic_op_inuser(int op, u32 oparg, int *oval, u32 __user *uaddr) @@ -85,7 +87,9 @@ out_pagefault_enable: * * Return: * 0 - On success - * <0 - On error + * -EFAULT - User access resulted in a page fault + * -EAGAIN - Atomic operation was unable to complete due to contention + * -ENOSYS - Function not implemented (only if !HAVE_FUTEX_CMPXCHG) */ static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,