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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 60C27C433FF for ; Mon, 12 Aug 2019 12:36:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D85D214C6 for ; Mon, 12 Aug 2019 12:36:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726516AbfHLMgO (ORCPT ); Mon, 12 Aug 2019 08:36:14 -0400 Received: from bilbo.ozlabs.org ([203.11.71.1]:41181 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726219AbfHLMgN (ORCPT ); Mon, 12 Aug 2019 08:36:13 -0400 Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 466b1Q0FR7z9sN6; Mon, 12 Aug 2019 22:36:10 +1000 (AEST) From: Michael Ellerman To: Thiago Jung Bauermann , linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org, Alexey Kardashevskiy , Anshuman Khandual , Benjamin Herrenschmidt , Christoph Hellwig , Mike Anderson , Paul Mackerras , Ram Pai , Claudio Carvalho , Anshuman Khandual , Thiago Jung Bauermann Subject: Re: [PATCH v3 08/16] powerpc/pseries/svm: Use shared memory for LPPACA structures In-Reply-To: <20190806052237.12525-9-bauerman@linux.ibm.com> References: <20190806052237.12525-1-bauerman@linux.ibm.com> <20190806052237.12525-9-bauerman@linux.ibm.com> Date: Mon, 12 Aug 2019 22:36:11 +1000 Message-ID: <875zn2sgqs.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thiago Jung Bauermann writes: > From: Anshuman Khandual > > LPPACA structures need to be shared with the host. Hence they need to be in > shared memory. Instead of allocating individual chunks of memory for a > given structure from memblock, a contiguous chunk of memory is allocated > and then converted into shared memory. Subsequent allocation requests will > come from the contiguous chunk which will be always shared memory for all > structures. > > While we are able to use a kmem_cache constructor for the Debug Trace Log, > LPPACAs are allocated very early in the boot process (before SLUB is > available) so we need to use a simpler scheme here. > > Introduce helper is_svm_platform() which uses the S bit of the MSR to tell > whether we're running as a secure guest. > > Signed-off-by: Anshuman Khandual > Signed-off-by: Thiago Jung Bauermann > --- > arch/powerpc/include/asm/svm.h | 26 ++++++++++++++++++++ > arch/powerpc/kernel/paca.c | 43 +++++++++++++++++++++++++++++++++- > 2 files changed, 68 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/include/asm/svm.h b/arch/powerpc/include/asm/svm.h > new file mode 100644 > index 000000000000..fef3740f46a6 > --- /dev/null > +++ b/arch/powerpc/include/asm/svm.h > @@ -0,0 +1,26 @@ > +/* SPDX-License-Identifier: GPL-2.0+ */ > +/* > + * SVM helper functions > + * > + * Copyright 2019 Anshuman Khandual, IBM Corporation. Are we sure this copyright date is correct? cheers