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=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 53BBCC433E0 for ; Wed, 24 Feb 2021 07:48:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F36A264ED0 for ; Wed, 24 Feb 2021 07:48:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233025AbhBXHsN (ORCPT ); Wed, 24 Feb 2021 02:48:13 -0500 Received: from mail.kernel.org ([198.145.29.99]:56804 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232244AbhBXHsL (ORCPT ); Wed, 24 Feb 2021 02:48:11 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6703F64ED0; Wed, 24 Feb 2021 07:47:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614152849; bh=RVf5GkQcDbIy/YKyojc1T9OWKopOggYUqzd/K3p18Gc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Fsl0Mazf9x2E9GV9w09rtf7Ll8pgIoQguOgdeJhYFyeEUmbYNcG1UC6w53UJKzFWO wHyhPW9cuxLtwAu7sFC/COAXk5Xl6v8yLSEz9V5sW+/EAHYisBXmzwJ3L5Fp9AowX2 t95iO76FJbBAxhWHNUguaWWcXr75AybyXNqARM38= Date: Wed, 24 Feb 2021 08:47:26 +0100 From: Greg KH To: Xiaoming Ni Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, sashal@kernel.org, tglx@linutronix.de, wangle6@huawei.com, zhengyejian1@huawei.com Subject: Re: [PATCH stable-rc queue/4.9 1/1] futex: Provide distinct return value when owner is exiting Message-ID: References: <20210222070328.102384-1-nixiaoming@huawei.com> <20210222070328.102384-2-nixiaoming@huawei.com> <3bc570f6-f8af-b0a2-4d62-13ed4adc1f33@huawei.com> <76f6a446-41db-3b7a-dcab-a85d0841654f@huawei.com> <2e8cf845-30ee-22c2-428a-b56e03cb49e4@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2e8cf845-30ee-22c2-428a-b56e03cb49e4@huawei.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Wed, Feb 24, 2021 at 09:41:01AM +0800, Xiaoming Ni wrote: > On 2021/2/23 21:00, Greg KH wrote: > > On Mon, Feb 22, 2021 at 10:11:37PM +0800, Xiaoming Ni wrote: > > > On 2021/2/22 20:09, Greg KH wrote: > > > > On Mon, Feb 22, 2021 at 06:54:06PM +0800, Xiaoming Ni wrote: > > > > > On 2021/2/22 18:16, Greg KH wrote: > > > > > > On Mon, Feb 22, 2021 at 03:03:28PM +0800, Xiaoming Ni wrote: > > > > > > > From: Thomas Gleixner > > > > > > > > > > > > > > commit ac31c7ff8624409ba3c4901df9237a616c187a5d upstream. > > > > > > This commit is already in the 4.9 tree. If the backport was incorrect, > > > > > > say that here, and describe what went wrong and why this commit fixes > > > > > > it. > > > > > > > > > > > > Also state what commit this fixes as well, otherwise this changelog just > > > > > > looks like it is being applied again to the tree, which doesn't make > > > > > > much sense. > > > > > > > > > > > > thanks, > > > > > > > > > > > > greg k-h > > > > > > . > > > > > > > > > > I wrote a cover for it. but forgot to adjust the title of the cover: > > > > > > > > > > https://lore.kernel.org/lkml/20210222070328.102384-1-nixiaoming@huawei.com/ > > > > > > > > > > > > > > > I found a dead code in the queue/4.9 branch of the stable-rc repository. > > > > > > > > > > 2021-02-03: > > > > > commit c27f392040e2f6 ("futex: Provide distinct return value when > > > > > owner is exiting") > > > > > The function handle_exit_race does not exist. Therefore, the > > > > > change in handle_exit_race() is ignored in the patch round. > > > > > > > > > > 2021-02-22: > > > > > commit e55cb811e612 ("futex: Cure exit race") > > > > > Define the handle_exit_race() function, > > > > > but no branch in the function returns EBUSY. > > > > > As a result, dead code occurs in the attach_to_pi_owner(): > > > > > > > > > > int ret = handle_exit_race(uaddr, uval, p); > > > > > ... > > > > > if (ret == -EBUSY) > > > > > *exiting = p; /* dead code */ > > > > > > > > > > To fix the dead code, modify the commit e55cb811e612 ("futex: Cure exit > > > > > race"), > > > > > or install a patch to incorporate the changes in handle_exit_race(). > > > > > > > > > > I am unfamiliar with the processing of the stable-rc queue branch, > > > > > and I cannot find the patch mail of the current branch in > > > > > https://lore.kernel.org/lkml/?q=%22futex%3A+Cure+exit+race%22 > > > > > Therefore, I re-integrated commit ac31c7ff8624 ("futex: Provide distinct > > > > > return value when owner is exiting"). > > > > > And wrote a cover (but forgot to adjust the title of the cover): > > > > > > > > > > https://lore.kernel.org/lkml/20210222070328.102384-1-nixiaoming@huawei.com/ > > > > > > > > So this is a "fixup" patch, right? > > > > > > > > Please clearly label it as such in your patch description and resend > > > > this as what is here I can not apply at all. > > > > > > > > thanks, > > > > > > > > greg k-h > > > > . > > > > > > > Thank you for your guidance. > > > I have updated the patch description and resent the patch based on > > > v4.9.258-rc1 > > > https://lore.kernel.org/lkml/20210222125352.110124-1-nixiaoming@huawei.com/ > > > > Can you please try 4.9.258 and let me know if this is still needed or > > not? > > > > thanks, > > > > greg k-h > > . > > > The dead code problem still exists in V4.9.258. No conflict occurs during my > patch integration. Do I need to correct the version number marked in the cc > table in the patch and resend the patch? Please do. thanks, greg k-h