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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A80F3C433F5 for ; Sun, 24 Apr 2022 19:23:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237458AbiDXT0c (ORCPT ); Sun, 24 Apr 2022 15:26:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233170AbiDXT0b (ORCPT ); Sun, 24 Apr 2022 15:26:31 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 47D7C62A07; Sun, 24 Apr 2022 12:23:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Xh7LUAmFoIqxYbksJd78ZOLHOPH0rZu20hznpGLh6Sc=; b=AUxGYIQrS3y3W3q8SWzPJltLQ9 CxG+f+R0sS2hArtvwedFK/KIQ0hukY2anrXqk/Sh2nYfpIRBGYl9+DrbjB7acifAtveO6BSnMm98C gZjhQS3bH9FVHS3UbbiWXOLOM5K0OtMPVDoMGQzxl3WOX5Md0Qkv6M2JftRCIpL7jOZH3x11Z8xAe uFdxQFZ+jnq12GqyZaITinJk7xQ0obhKIB7lrop24PuziXQmeV6zzqdyD4B+o1lufiGfj141pOaAJ qI8+CrZMwppNccNn4bX6IQDLL2kT3rsQNxQtx19veCIsuntpm5kqgmjgmKjoM0Mw1xrRXjSDcaYBT vf5WiztA==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nihpF-00887x-E1; Sun, 24 Apr 2022 19:23:17 +0000 Date: Sun, 24 Apr 2022 20:23:17 +0100 From: Matthew Wilcox To: Junwen Wu Cc: adobriyan@gmail.com, akpm@linux-foundation.org, ddiss@suse.de, fweimer@redhat.com, keescook@chromium.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] proc: limit schedstate node write operation Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Sun, Apr 24, 2022 at 03:23:54PM +0000, Junwen Wu wrote: > From: Matthew Wilcox > > On Sat, Apr 23, 2022 at 02:31:04AM +0000, Junwen Wu wrote: > > Whatever value is written to /proc/$pid/sched, a task's schedstate data > > will reset.In some cases, schedstate will drop by accident. We restrict > > writing a certain value to this node before the data is reset. > > ... and break the existing scripts which expect the current behaviour. > > > Hi, Matthew,can you describe it in more detail. What detail do you need? Existing scripts depend on the existing behaviour. Your change to the behaviour will break them. That's not allowed, so your patch is rejected. 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B90AC433EF for ; Sat, 30 Apr 2022 13:49:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239521AbiD3NxH (ORCPT ); Sat, 30 Apr 2022 09:53:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234594AbiD3NxG (ORCPT ); Sat, 30 Apr 2022 09:53:06 -0400 Received: from m12-15.163.com (m12-15.163.com [220.181.12.15]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 42A6D66CBC; Sat, 30 Apr 2022 06:49:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=HoFZI NC4aFfCbd4HhSrPARXqzc6R21KBitpAHIryZhY=; b=o0tsFvfAcrcQlkQiuULQo 3BN5FkfyfmtSHss9SIn3I6vWYVJNRk/H/Gj0PYEctE3QZPlSu3P7tXciRyfYxHGQ Jx8i8TPex9DxcDLPLVQ1g+zfYajGPhuIx/R1WFEo9a77T6/vmqebubJ8d+6eSod6 SbVIkFR20brEkcFBl1xaUY= Received: from localhost (unknown [120.229.67.207]) by smtp11 (Coremail) with SMTP id D8CowAAnj58aPm1if+mzAA--.19060S2; Sat, 30 Apr 2022 21:48:11 +0800 (CST) From: Junwen Wu To: willy@infradead.org, Junwen Wu Cc: adobriyan@gmail.com, akpm@linux-foundation.org, ddiss@suse.de, fweimer@redhat.com, keescook@chromium.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] proc: limit schedstate node write operation Date: Sat, 30 Apr 2022 13:48:04 +0000 Message-ID: (raw) X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: D8CowAAnj58aPm1if+mzAA--.19060S2 X-Coremail-Antispam: 1Uf129KBjvdXoW7Wr1kArWxAw15Zr1DuFyDJrb_yoW3KrbE9w 15J3sxu34jqFn5KFZFkr4Yqr1ag3y8GFWDW3ykZrnrXrZ8AFWvgF17KrZ5ZF1fXrsrJrn8 CrnYvFWq9Fyj9jkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7VUjDPE5UUUUU== X-Originating-IP: [120.229.67.207] X-CM-SenderInfo: 5zxgtvxprqqiywtou0bp/1tbisRzybVXlppCxtAAAsx Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Message-ID: <20220430134804.Ar0IZzDtXU90u5wAlSNgagGOKft2cryPqCY3wCuZ-Rg@z> From: Matthew Wilcox On Sun, Apr 24, 2022 at 03:23:54PM +0000, Junwen Wu wrote: > From: Matthew Wilcox > > On Sat, Apr 23, 2022 at 02:31:04AM +0000, Junwen Wu wrote: > > Whatever value is written to /proc/$pid/sched, a task's schedstate data > > will reset.In some cases, schedstate will drop by accident. We restrict > > writing a certain value to this node before the data is reset. > > ... and break the existing scripts which expect the current behaviour. > > > Hi, Matthew,can you describe it in more detail. > What detail do you need? Existing scripts depend on the existing > behaviour. Your change to the behaviour will break them. That's not > allowed, so your patch is rejected. ooh ,just how to operate the node make the script break. I write data to this node can work well. Thanks