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 7D455C63797 for ; Wed, 1 Feb 2023 11:01:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232361AbjBALBd (ORCPT ); Wed, 1 Feb 2023 06:01:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59102 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229582AbjBALBb (ORCPT ); Wed, 1 Feb 2023 06:01:31 -0500 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0A61E9ECB; Wed, 1 Feb 2023 03:01:26 -0800 (PST) Received: from zn.tnic (p5de8e9fe.dip0.t-ipconnect.de [93.232.233.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id D917A1EC04C1; Wed, 1 Feb 2023 12:01:24 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1675249284; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=z8r3tqpTOCugqbjchw7davFdI781zmRXaztbV66xvXI=; b=YFmDe5qmaGXQ9822SHvm9YThC0H082UQm2dw0ZO8kjxGAvEoBhVAPDd4p+bpK5+SzgnKwe 0fHkgMN2IwuWBO/ZkctytZODottaFy/JljNGplig/M53tMAH5E1LTYrM/QTAby2ZlhOpH9 Ty8Pn9zG3mXo9EJXE/XpdgwwlvoaY14= Date: Wed, 1 Feb 2023 12:01:18 +0100 From: Borislav Petkov To: Rick Edgecombe Cc: x86@kernel.org, "H . Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H . J . Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , Weijiang Yang , "Kirill A . Shutemov" , John Allen , kcc@google.com, eranian@google.com, rppt@kernel.org, jamorris@linux.microsoft.com, dethoma@microsoft.com, akpm@linux-foundation.org, Andrew.Cooper3@citrix.com, christina.schimpe@intel.com Subject: Re: [PATCH v5 06/39] x86/fpu: Add helper for modifying xstate Message-ID: References: <20230119212317.8324-1-rick.p.edgecombe@intel.com> <20230119212317.8324-7-rick.p.edgecombe@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230119212317.8324-7-rick.p.edgecombe@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Thu, Jan 19, 2023 at 01:22:44PM -0800, Rick Edgecombe wrote: > +void fpregs_lock_and_load(void) > +{ > + /* > + * fpregs_lock() only disables preemption (mostly). So modifying state > + * in an interrupt could screw up some in progress fpregs operation, > + * but appear to work. Warn about it. I don't like comments where it sounds like we don't know what we're doing. "Appear to work"? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette