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[23.128.96.18]) by mx.google.com with ESMTP id b6si2742971edu.126.2021.08.19.01.05.18; Thu, 19 Aug 2021 01:05:50 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@alien8.de header.s=dkim header.b=rSdcwANU; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=alien8.de Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236852AbhHSIAp (ORCPT + 99 others); Thu, 19 Aug 2021 04:00:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231909AbhHSIAp (ORCPT ); Thu, 19 Aug 2021 04:00:45 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B241C061575 for ; Thu, 19 Aug 2021 01:00:09 -0700 (PDT) Received: from zn.tnic (p200300ec2f0f6a004ea6615b49afdf70.dip0.t-ipconnect.de [IPv6:2003:ec:2f0f:6a00:4ea6:615b:49af:df70]) (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 AC7211EC053B; Thu, 19 Aug 2021 10:00:02 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1629360002; 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=qnhA5cmtkd6svGydZQuQmhOhtjiS6e2nB/ckrDMGzMY=; b=rSdcwANU4JhC026Wfi1ElMwS1Lt13JctmcOb7HmrOu0VhLwSeoYClbV4C5q8l5M1WC9o67 LG7U5o9ngVNiAdVinjaf/8ouR6vbPVSNvCdxg78/pkmdmk0k4UONI7UGEhuf/01OPutK/i xRFqEoICV8EiDPaZ6wN92UmqvTEQkQo= Date: Thu, 19 Aug 2021 10:00:41 +0200 From: Borislav Petkov To: "Bae, Chang Seok" Cc: "Macieira, Thiago" , "Lutomirski, Andy" , "tglx@linutronix.de" , "mingo@kernel.org" , "x86@kernel.org" , "Brown, Len" , "Hansen, Dave" , "Liu, Jing2" , "Shankar, Ravi V" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v9 12/26] x86/fpu/xstate: Use feature disable (XFD) to protect dynamic user state Message-ID: References: <20210730145957.7927-1-chang.seok.bae@intel.com> <20210730145957.7927-13-chang.seok.bae@intel.com> <3181031.RqgVF4sTRC@tjmaciei-mobl5> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 18, 2021 at 09:37:58PM +0000, Bae, Chang Seok wrote: > What if it never happens? It will be just the same as XGETBV(0). I > think on the flip side there is also a benefit of maintaining a simple > API as possible. Dude, why are you still pointlessly harping on this? How is adding adding another trivial prctl which will be simply forwarding XCR0 for now, making the API more complex? If you don't wanna do it just say so - someone else will. Geez. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette