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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34CA2C64EC3 for ; Wed, 1 Feb 2023 11:01:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7173E6B0071; Wed, 1 Feb 2023 06:01:38 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 69FD76B0072; Wed, 1 Feb 2023 06:01:38 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 54B0E6B0078; Wed, 1 Feb 2023 06:01:38 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 3EB836B0071 for ; Wed, 1 Feb 2023 06:01:38 -0500 (EST) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 1A66B40794 for ; Wed, 1 Feb 2023 11:01:38 +0000 (UTC) X-FDA: 80418432276.09.CE49C0C Received: from mail.skyhub.de (mail.skyhub.de [5.9.137.197]) by imf13.hostedemail.com (Postfix) with ESMTP id 66FBC20031 for ; Wed, 1 Feb 2023 11:01:28 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=temperror ("DNS error when getting key") header.d=alien8.de header.s=dkim header.b=YFmDe5qm; spf=temperror (imf13.hostedemail.com: error in processing during lookup of bp@alien8.de: DNS error) smtp.mailfrom=bp@alien8.de; dmarc=temperror reason="query timed out" header.from=alien8.de (policy=temperror) 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> X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: bhnzmett63cpzx49yeeniczwu9h7ca51 X-Rspamd-Queue-Id: 66FBC20031 X-HE-Tag: 1675249288-745923 X-HE-Meta: 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 +ImQ1jQD 6HNyoE9OlijV9MJSzQZIVOFLLYkcVO7KmkhsaeSp6haqWAGObQHwThRGDH4c69OQCrjZmnRc7zDry1qnr4IRxYFE1jwI+fybNd7Z0V7F2XHKwPcSEWZEalT1R7PVE8s5O97Iyl4MHDUdntWw7wkQkjK7qg0zzQzEEwaipglnW0kxuQW3/8DxTMX/q86sKW7Z7HmdVSXHetml2E67ZmSPG6cJcELiewsU/NT/O X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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