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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 DA101C35242 for ; Tue, 11 Feb 2020 22:50:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1B4020714 for ; Tue, 11 Feb 2020 22:50:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581461444; bh=XV1MMCtQP/VUtU4M6HqgIW/VlmatPHwn+NBw1GlBfxE=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=ExTP4Y5Br9lKBK7+kCt3oteo/+d/JNpCb8oRhl0iGMlbfHpMPlwcW7cJ/REH9WFNb wmKJd0vMMJHxXF0uPe0hT+emPYwyu7Lok9JJO31qOzyAE++eE/r7PDoOvZCLK73dQa PSoE93tzbWbhRYTu7CNJeuTNr4Eix1H6qpL2gb4I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727690AbgBKWuo (ORCPT ); Tue, 11 Feb 2020 17:50:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:34040 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727199AbgBKWun (ORCPT ); Tue, 11 Feb 2020 17:50:43 -0500 Received: from mail-wr1-f51.google.com (mail-wr1-f51.google.com [209.85.221.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B7B862168B for ; Tue, 11 Feb 2020 22:50:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581461443; bh=XV1MMCtQP/VUtU4M6HqgIW/VlmatPHwn+NBw1GlBfxE=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=ploUTxCjV3VZ6tRSQcERV/2TkHxK4a61WSt0RGq4gUTpKMu1W1hLhTbWDXl30txGR vCmP4QO6itTbAGDg+EqexNRphI3QMVIY4Q3Wz7WZ0o5H7abZnHtqTVSRuxOqn5o2dF 7lbJQQGylkDDRs7ouXBoO8wkt7ZIl+bnEt2iQi0U= Received: by mail-wr1-f51.google.com with SMTP id g3so13517902wrs.12 for ; Tue, 11 Feb 2020 14:50:42 -0800 (PST) X-Gm-Message-State: APjAAAWZd8tIWN/sk407e9CwJkZgwAxQR6QG3pBe11vVF/kxQrA+kt51 9y62LumA8hAHpzqK2Qwtd8ljfjVLrKg1zeX9n8pcww== X-Google-Smtp-Source: APXvYqzqJ1AlSDY2ZRDO05AMScFqgtaEyb1UuVzqt0WKNedpg8GD4u5J3WkIoYB+03YMjv6Q0h3O47HFfxgY+9Q1m0c= X-Received: by 2002:adf:a354:: with SMTP id d20mr10861134wrb.257.1581461441006; Tue, 11 Feb 2020 14:50:41 -0800 (PST) MIME-Version: 1.0 References: <20200211135256.24617-1-joro@8bytes.org> <20200211135256.24617-63-joro@8bytes.org> In-Reply-To: <20200211135256.24617-63-joro@8bytes.org> From: Andy Lutomirski Date: Tue, 11 Feb 2020 14:50:29 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 62/62] x86/sev-es: Add NMI state tracking To: Joerg Roedel Cc: X86 ML , "H. Peter Anvin" , Andy Lutomirski , Dave Hansen , Peter Zijlstra , Thomas Hellstrom , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , LKML , kvm list , Linux Virtualization , Joerg Roedel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 11, 2020 at 5:53 AM Joerg Roedel wrote: > > From: Joerg Roedel > > Keep NMI state in SEV-ES code so the kernel can re-enable NMIs for the > vCPU when it reaches IRET. This patch is overcomplicated IMO. Just do the magic incantation in C from do_nmi or from here: /* * For ease of testing, unmask NMIs right away. Disabled by * default because IRET is very expensive. If you do the latter, you'll need to handle the case where the NMI came from user mode. The ideal solution is do_nmi, I think. if (static_cpu_has(X86_BUG_AMD_FORGOT_ABOUT_NMI)) sev_es_unmask_nmi(); Feel free to use X86_FEATURE_SEV_ES instead :) --Andu