Received: by 2002:a6b:500f:0:0:0:0:0 with SMTP id e15csp955475iob; Thu, 28 Apr 2022 14:52:55 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzdMBIU1A4Q52uAnuJ8kX4i1Gqo/obOIjcvQ1Pj/mFeGxS3bi0Np6kQ12CmKmIbL0BX68iI X-Received: by 2002:a05:6512:169e:b0:470:2124:63fb with SMTP id bu30-20020a056512169e00b00470212463fbmr25786787lfb.616.1651182775298; Thu, 28 Apr 2022 14:52:55 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1651182775; cv=none; d=google.com; s=arc-20160816; b=OpX1BG16UnxOpEKiXVSgzIoE+IP+u0ft4Pz9xqs8lxxogq6iqdNESYvLO7G6YzKcdO wILFzi0S8CtiqUpeClsh4Oxs8ZMfIDoSAYwfb0+p6yjnFsldgO7d6FbBCfOnjEtMknQj vobTq+8Nu5tLdKM4OA7cSYwpz2a45Y9qbXxR0ZH3HxsJz6QAZBLnNfrUiwdmR+K1a2JF Umwkn5wakVFivWSW9UmjCaebh3hJwUu3Am0JWzMwNSywu+OtrMTvoD0orbAKKt7k1itM d/S9LUl682H4zXMAcm4b6CmBbCWaP0lzCjlRqpa1rqOe5GBtV9G1JOSgT0huBdmiiByQ 06Nw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=pAUQNOu/Xvx7sFYGMIzT4ewYo8Q7kV8gZxOmlw0y+YM=; b=ZZGGecfpHk7r7s6GAa6dUQNM/EWvv7089xhxQj7WDoCUKTvtTvvyQFv/qwpTN3WUmY kzn+zPLhQuDUjnBQnrUfQmB39Vi0yXz1oyfLIm33RMa3VsspZgzJLW61hLTE43uKDx8p orFn+CKinu8TJzPa4TrIFs72XztvoKJoT7FVS8uD3ddyeipKz6BDApX79KSXVgQvTOLo 6zXm5HXo2VuWq4BiYEGJAC4XyAT4FrP+Z2SkbnBK57LDhtP/2AUS0QUjK8Qm7CiXNDS4 MQewD8JEUPiiV5t8oKsM3+Fjf83bu1yQ80b3aGCvWG1SpitCCrASnUeJabqiPJyy6t6E 6H5Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=jqnHwtfw; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id br32-20020a056512402000b0044a422b04bcsi5469856lfb.295.2022.04.28.14.52.27; Thu, 28 Apr 2022 14:52:55 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=desiato.20200630 header.b=jqnHwtfw; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344906AbiD1JbV (ORCPT + 99 others); Thu, 28 Apr 2022 05:31:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346967AbiD1J2P (ORCPT ); Thu, 28 Apr 2022 05:28:15 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 658BE7C148 for ; Thu, 28 Apr 2022 02:24:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; 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=pAUQNOu/Xvx7sFYGMIzT4ewYo8Q7kV8gZxOmlw0y+YM=; b=jqnHwtfwPzIMOxRJieRwoVN/LW /DxvM9UQ768YHGbiJBLdVw9xqqWNmPGGbOcxAgDHztVX04XSnvNkIhMBzhxEzVn5XBaLXtbcE4toA 05ALgAGxnAIh4J0a37Q2e+i3/wF6PFpmt0GPpUPtb5t56uL4XEg2BhC5lrS9f3Ot1gCnlPooNreNv v36cre5Gr3G2xyncU0RmtlhIlIuEDsnrjstUTxcQJfnJuwBPo5jdDc3kUzTFz4OL8wjB/8M1G2MJr V8fKp5e7NNXwKN0Efbbru9omO9wpAitwKm6jEiKHaR6HfhFaCg7ws6DZMYhxObotHq9+3nwDgd2E4 qh7gWbuQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nk0OF-009JKd-N5; Thu, 28 Apr 2022 09:24:47 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id D7B51300C88; Thu, 28 Apr 2022 11:24:45 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id B93B22029F872; Thu, 28 Apr 2022 11:24:45 +0200 (CEST) Date: Thu, 28 Apr 2022 11:24:45 +0200 From: Peter Zijlstra To: Jun Miao Cc: elver@google.com, dvyukov@google.com, ryabinin.a.a@gmail.com, bigeasy@linutronix.de, qiang1.zhang@intel.com, andreyknvl@gmail.com, kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, akpm@linux-foundation.org Subject: Re: [PATCH v2] irq_work: Make irq_work_queue_on() NMI-safe again Message-ID: References: <20220427135549.20901-1-jun.miao@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220427135549.20901-1-jun.miao@intel.com> X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED,SPF_HELO_NONE, SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 27, 2022 at 09:55:49PM +0800, Jun Miao wrote: > We should not put NMI unsafe code in irq_work_queue_on(). Why not, irq_work_queue_on() is not NMI safe. Only irq_work_queue() is.