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 683D3EB64DC for ; Wed, 21 Jun 2023 07:42:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231452AbjFUHmJ (ORCPT ); Wed, 21 Jun 2023 03:42:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231487AbjFUHlf (ORCPT ); Wed, 21 Jun 2023 03:41:35 -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 E00671730; Wed, 21 Jun 2023 00:41:21 -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=CVccEsCRdBl+DyRFyKD9+7GUkI4WQ8YmpzDSeZ8LLAU=; b=UBnRecR5iA9zqnqiBJcqz/55xX A3eIbAZ/GIqVk7aCdQreoS1qGWET767UVs912HwOcxufzXOO6gUWD1lYTvrGW7Q+fHkeUp2WRyI6b Czg6gAQuewKvft8SHyw6qZTWCNcab/QS9ZetefpYPqBSVS5pgLHgsFt1MligyngRxD/HNmVH+ScX2 fEOd1fOg+ZxEKwm/K94SXpWKXJUas9bYQJ48cm1/pUj94sr6QTUt2j1j8sbAKuUkw7xrA3l1Rgrql zJjWxJwuMHLs1SMV/olYwiiBxyLDVYkMxk7yfgnMFm/IFtCt+2LEq63jT5hlAIRzGOM50+N3H5US0 pFYuljTQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qBsSg-00HITA-0Z; Wed, 21 Jun 2023 07:41:09 +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)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id AA29F300222; Wed, 21 Jun 2023 09:41:05 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 9424D2BC73BD5; Wed, 21 Jun 2023 09:41:05 +0200 (CEST) Date: Wed, 21 Jun 2023 09:41:05 +0200 From: Peter Zijlstra To: Waiman Long Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Josh Poimboeuf , Pawan Gupta , Jacob Pan , Len Brown , linux-kernel@vger.kernel.org, x86@kernel.org, linux-pm@vger.kernel.org, Robin Jarry , Joe Mario Subject: Re: [PATCH v2 1/5] x86/speculation: Provide a debugfs file to dump SPEC_CTRL MSRs Message-ID: <20230621074105.GE2046280@hirez.programming.kicks-ass.net> References: <20230620140625.1001886-1-longman@redhat.com> <20230620140625.1001886-2-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230620140625.1001886-2-longman@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 20, 2023 at 10:06:21AM -0400, Waiman Long wrote: > Sometimes it is useful to know the states the SPEC_CTRL MSRs to see what > mitigations are enabled at run time. Provide a new x86/spec_ctrl_msrs > debugfs file to dump the cached versions of the current SPEC_CTRL MSRs. > Pff, clearly I can't even read email anymore.. We don't do this for any of the other MSRs, so why start now?