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,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 BE9ECC64E7A for ; Tue, 1 Dec 2020 07:39:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 41CED2085B for ; Tue, 1 Dec 2020 07:39:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="evTFk2D5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728216AbgLAHj5 (ORCPT ); Tue, 1 Dec 2020 02:39:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38402 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727328AbgLAHj5 (ORCPT ); Tue, 1 Dec 2020 02:39:57 -0500 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0C7AC0613CF for ; Mon, 30 Nov 2020 23:39:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.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=7fCxfMgvNP5evF0Sh/ywGl1CmE7pC2KJxA7sTdoG65I=; b=evTFk2D5OoAFmqTYLiJLgwhV25 MhIWsV0KEKGqhtcAlkp4TnaHPPhu7hhGKtbeZB3TP8Oy7Iy5DRf6GRsVhrOt72VppnzLYwruuFJTT JSBE7JrUW4XM06t8h/aHauLxahyveoOr6NWvV0AjCRdmo/rwJVHxIcZAOFYBYRG1LG8JqoeNBAmDE 4xtKGrzg/8mEc4Nd0W0gxApIUVljxaJQ0Dw5EDSbx85mexSs6vevRxG9+TmXCs2PObU1vDHSbXMIE RqpENVRXU9EklciBvY0TLxYNZOuDBaEpTT4k6lXkUNu0RjzzsWYrEN9N/DUA2EB4mcVmJZw7YYYMQ sonGzBpA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kk0Fi-0007Qd-Gk; Tue, 01 Dec 2020 07:39:10 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 462EC300DAE; Tue, 1 Dec 2020 08:39:06 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 34C6C2BBF26BF; Tue, 1 Dec 2020 08:39:06 +0100 (CET) Date: Tue, 1 Dec 2020 08:39:06 +0100 From: Peter Zijlstra To: Linus Torvalds Cc: Thomas Gleixner , "Paul E. McKenney" , Linux Kernel Mailing List , the arch/x86 maintainers Subject: Re: [GIT pull] locking/urgent for v5.10-rc6 Message-ID: <20201201073906.GP2414@hirez.programming.kicks-ass.net> References: <160665707945.2808.5384034634184489471.tglx@nanos> <160665708065.2808.15317906761841446715.tglx@nanos> <20201130075651.GJ2414@hirez.programming.kicks-ass.net> 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-kernel@vger.kernel.org On Mon, Nov 30, 2020 at 09:55:44AM -0800, Linus Torvalds wrote: > Yes, yes, I can very well imagine some hardware doing a "idle until > you sense an interrupt, but don't actually take it". It's not > _impossible_. But it's certainly not normal. A lot of hardware actually does that, including modern x86. But yes, not nearly everything.