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=-12.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 79F33C433FE for ; Thu, 9 Sep 2021 07:25:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6094E6109E for ; Thu, 9 Sep 2021 07:25:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352591AbhIIH0n (ORCPT ); Thu, 9 Sep 2021 03:26:43 -0400 Received: from pegase2.c-s.fr ([93.17.235.10]:37307 "EHLO pegase2.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230424AbhIIH0l (ORCPT ); Thu, 9 Sep 2021 03:26:41 -0400 Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4H4rBd5z43z9sWc; Thu, 9 Sep 2021 09:25:29 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id tI4gb1MB9n_o; Thu, 9 Sep 2021 09:25:29 +0200 (CEST) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4H4rBd4d9gz9sWb; Thu, 9 Sep 2021 09:25:29 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 837618B77E; Thu, 9 Sep 2021 09:25:29 +0200 (CEST) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id D01rvl7fvhrg; Thu, 9 Sep 2021 09:25:29 +0200 (CEST) Received: from po9476vm.idsi0.si.c-s.fr (po22017.idsi0.si.c-s.fr [192.168.7.20]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 9CE478B77D; Thu, 9 Sep 2021 09:25:27 +0200 (CEST) Subject: Re: [PATCH v3 8/8] treewide: Replace the use of mem_encrypt_active() with cc_platform_has() To: Tom Lendacky , linux-kernel@vger.kernel.org, x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, iommu@lists.linux-foundation.org, kvm@vger.kernel.org, linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-graphics-maintainer@vmware.com, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org Cc: Sathyanarayanan Kuppuswamy , Brijesh Singh , Peter Zijlstra , Dave Hansen , Paul Mackerras , Will Deacon , Andi Kleen , Baoquan He , Christian Borntraeger , Joerg Roedel , Christoph Hellwig , David Airlie , Ingo Molnar , Dave Young , Tianyu Lan , Thomas Zimmermann , Vasily Gorbik , Heiko Carstens , Maarten Lankhorst , Maxime Ripard , Borislav Petkov , Andy Lutomirski , Thomas Gleixner , Daniel Vetter References: <46a18427dc4e9dda985b10e472965e3e4c769f1d.1631141919.git.thomas.lendacky@amd.com> From: Christophe Leroy Message-ID: Date: Thu, 9 Sep 2021 07:25:25 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <46a18427dc4e9dda985b10e472965e3e4c769f1d.1631141919.git.thomas.lendacky@amd.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/8/21 10:58 PM, Tom Lendacky wrote: > > diff --git a/arch/powerpc/include/asm/mem_encrypt.h b/arch/powerpc/include/asm/mem_encrypt.h > index ba9dab07c1be..2f26b8fc8d29 100644 > --- a/arch/powerpc/include/asm/mem_encrypt.h > +++ b/arch/powerpc/include/asm/mem_encrypt.h > @@ -10,11 +10,6 @@ > > #include > > -static inline bool mem_encrypt_active(void) > -{ > - return is_secure_guest(); > -} > - > static inline bool force_dma_unencrypted(struct device *dev) > { > return is_secure_guest(); > diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c > index 87f001b4c4e4..c083ecbbae4d 100644 > --- a/arch/powerpc/platforms/pseries/svm.c > +++ b/arch/powerpc/platforms/pseries/svm.c > @@ -8,6 +8,7 @@ > > #include > #include > +#include > #include > #include > #include > @@ -63,7 +64,7 @@ void __init svm_swiotlb_init(void) > > int set_memory_encrypted(unsigned long addr, int numpages) > { > - if (!mem_encrypt_active()) > + if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) > return 0; > > if (!PAGE_ALIGNED(addr)) > @@ -76,7 +77,7 @@ int set_memory_encrypted(unsigned long addr, int numpages) > > int set_memory_decrypted(unsigned long addr, int numpages) > { > - if (!mem_encrypt_active()) > + if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) > return 0; > > if (!PAGE_ALIGNED(addr)) This change unnecessarily complexifies the two functions. This is due to cc_platform_has() being out-line. It should really remain inline. Before the change we got: 0000000000000000 <.set_memory_encrypted>: 0: 7d 20 00 a6 mfmsr r9 4: 75 29 00 40 andis. r9,r9,64 8: 41 82 00 48 beq 50 <.set_memory_encrypted+0x50> c: 78 69 04 20 clrldi r9,r3,48 10: 2c 29 00 00 cmpdi r9,0 14: 40 82 00 4c bne 60 <.set_memory_encrypted+0x60> 18: 7c 08 02 a6 mflr r0 1c: 7c 85 23 78 mr r5,r4 20: 78 64 85 02 rldicl r4,r3,48,20 24: 61 23 f1 34 ori r3,r9,61748 28: f8 01 00 10 std r0,16(r1) 2c: f8 21 ff 91 stdu r1,-112(r1) 30: 48 00 00 01 bl 30 <.set_memory_encrypted+0x30> 30: R_PPC64_REL24 .ucall_norets 34: 60 00 00 00 nop 38: 38 60 00 00 li r3,0 3c: 38 21 00 70 addi r1,r1,112 40: e8 01 00 10 ld r0,16(r1) 44: 7c 08 03 a6 mtlr r0 48: 4e 80 00 20 blr 50: 38 60 00 00 li r3,0 54: 4e 80 00 20 blr 60: 38 60 ff ea li r3,-22 64: 4e 80 00 20 blr After the change we get: 0000000000000000 <.set_memory_encrypted>: 0: 7c 08 02 a6 mflr r0 4: fb c1 ff f0 std r30,-16(r1) 8: fb e1 ff f8 std r31,-8(r1) c: 7c 7f 1b 78 mr r31,r3 10: 38 60 00 00 li r3,0 14: 7c 9e 23 78 mr r30,r4 18: f8 01 00 10 std r0,16(r1) 1c: f8 21 ff 81 stdu r1,-128(r1) 20: 48 00 00 01 bl 20 <.set_memory_encrypted+0x20> 20: R_PPC64_REL24 .cc_platform_has 24: 60 00 00 00 nop 28: 2c 23 00 00 cmpdi r3,0 2c: 41 82 00 44 beq 70 <.set_memory_encrypted+0x70> 30: 7b e9 04 20 clrldi r9,r31,48 34: 2c 29 00 00 cmpdi r9,0 38: 40 82 00 58 bne 90 <.set_memory_encrypted+0x90> 3c: 38 60 00 00 li r3,0 40: 7f c5 f3 78 mr r5,r30 44: 7b e4 85 02 rldicl r4,r31,48,20 48: 60 63 f1 34 ori r3,r3,61748 4c: 48 00 00 01 bl 4c <.set_memory_encrypted+0x4c> 4c: R_PPC64_REL24 .ucall_norets 50: 60 00 00 00 nop 54: 38 60 00 00 li r3,0 58: 38 21 00 80 addi r1,r1,128 5c: e8 01 00 10 ld r0,16(r1) 60: eb c1 ff f0 ld r30,-16(r1) 64: eb e1 ff f8 ld r31,-8(r1) 68: 7c 08 03 a6 mtlr r0 6c: 4e 80 00 20 blr 70: 38 21 00 80 addi r1,r1,128 74: 38 60 00 00 li r3,0 78: e8 01 00 10 ld r0,16(r1) 7c: eb c1 ff f0 ld r30,-16(r1) 80: eb e1 ff f8 ld r31,-8(r1) 84: 7c 08 03 a6 mtlr r0 88: 4e 80 00 20 blr 90: 38 60 ff ea li r3,-22 94: 4b ff ff c4 b 58 <.set_memory_encrypted+0x58>