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 35FE5ECAAA3 for ; Thu, 25 Aug 2022 22:11:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244316AbiHYWLU (ORCPT ); Thu, 25 Aug 2022 18:11:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42082 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244296AbiHYWLJ (ORCPT ); Thu, 25 Aug 2022 18:11:09 -0400 Received: from mail-vs1-xe2c.google.com (mail-vs1-xe2c.google.com [IPv6:2607:f8b0:4864:20::e2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0BCB15AA2F for ; Thu, 25 Aug 2022 15:11:04 -0700 (PDT) Received: by mail-vs1-xe2c.google.com with SMTP id m66so22218370vsm.12 for ; Thu, 25 Aug 2022 15:11:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc; bh=SB92LtmoHMRtHt7Hl06TY3zfz9SgbeIY+18JgkEA/Kw=; b=rxBaX9GtAHIyCKVT9OlFJ5ELgjONaqWbswYyMmc0IpaFpMhlOiy8LOLvUjFu4eG0l+ VSSV8gc74fFwX77LQutccYWVx/2ShLo56Qjw3siRY7DJrg5ujWfL+S4qzDfHpqtXI6cM xpGhTDNIsT5EHPk4igSj/Jty+CpW/bPi9mvrVp0FGuJ1Ug82zxj5uK+zCInjSbujRGCH 9+L3rFES95GOmEJgHVu9xQHLYBYSxpkAbbh17AVdbctP3VplwNAlG/PN0kSBbPA5WJHp HfsenyXKBo1/dJoQfQUDkut9q/v0KXUdvOUBHnD9Q14TiQ7oezOtiMKI8aUKgxZDuRS4 IceQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc; bh=SB92LtmoHMRtHt7Hl06TY3zfz9SgbeIY+18JgkEA/Kw=; b=wnTXLYpd8WJarzuXN4gZi8xsDVyjyZKRdB+65O57Moykq+vtJePXkm5LiLZ7GXh+kw Oqi+dnk55Rn07bTG22JKBU99aSGxk3BzQ4ELXwBzpBJvEGPyZA9lr+PLMg347/4fv/pM utP2M0mUocLPXQcmFqRbImx4R6/SNM1s6KPEs+YmgqQCaPbx6KevYdrj7PJAOQC6BL/X 7UfOVcwlhYOsCsUBc/sfsf3fES1dlvLrska6CobvYw+5HJwipQvt2ZGkieWpN9SIrI5i GYGY1eZocfEO43qVtWdmzbcS2vB3cCQQ6/89yn/dGXu3xeErHshp6W5qvts6z4VOnWz0 FEPg== X-Gm-Message-State: ACgBeo2DQWxLe19g899Tyozr4W71HyrXpSwVhGHyn2MpLDH1VZ2QGaUl z5sIvMqTBIZ1Oww7CNZnbAmFXLvlgT9OORWvaHq5mOqrQJiAhg== X-Google-Smtp-Source: AA6agR7sG+E2eIZTS8/PCVBZmFGZOXjK0hekyG2+zMof3C+l+zjS1OgUOwPyYn8TJK6I43MyYej9/F6TJpM1idvnQl0= X-Received: by 2002:a67:e089:0:b0:390:465e:aacb with SMTP id f9-20020a67e089000000b00390465eaacbmr2462660vsl.4.1661465463579; Thu, 25 Aug 2022 15:11:03 -0700 (PDT) MIME-Version: 1.0 References: <20220614120231.48165-1-kirill.shutemov@linux.intel.com> In-Reply-To: From: Dionna Amalie Glaze Date: Thu, 25 Aug 2022 15:10:52 -0700 Message-ID: Subject: Re: [PATCH v4 4/4] x86/sev: Add SNP-specific unaccepted memory support To: Tom Lendacky Cc: LKML , "the arch/x86 maintainers" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "Kirill A. Shutemov" , "H. Peter Anvin" , Michael Roth , Joerg Roedel , Andy Lutomirski , Peter Zijlstra Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > Add SNP-specific hooks to the unaccepted memory support in the boot > path (__accept_memory()) and the core kernel (accept_memory()) in order > to support booting SNP guests when unaccepted memory is present. Without > this support, SNP guests will fail to boot and/or panic() when unaccepted > memory is present in the EFI memory map. > > The process of accepting memory under SNP involves invoking the hypervisor > to perform a page state change for the page to private memory and then > issuing a PVALIDATE instruction to accept the page. Thanks for this update! Tests show the boot performance shaves off a good few seconds over eager acceptance, and it'll get better when we have on-demand pinning. The uncaught #VC exception is still there for 256GB machines and larger though. -- -Dionna Glaze, PhD (she/her)