Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754991AbdIGJiu (ORCPT ); Thu, 7 Sep 2017 05:38:50 -0400 Received: from mail.skyhub.de ([5.9.137.197]:47782 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754807AbdIGJis (ORCPT ); Thu, 7 Sep 2017 05:38:48 -0400 Date: Thu, 7 Sep 2017 11:38:37 +0200 From: Borislav Petkov To: x86-ml Cc: Brijesh Singh , Boris Ostrovsky , "Lendacky, Thomas" , "linux-kernel@vger.kernel.org" , Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner Subject: [PATCH] x86/mm: Make the SME mask a u64 Message-ID: <20170907093837.76zojtkgebwtqc74@pd.tnic> References: <4c07148a-5d97-0fc2-aa9b-1db31429736d@oracle.com> <20170906092618.fkvzrqx32z6iqf2t@pd.tnic> <20170906094504.6pp4xdsmcxaympth@pd.tnic> <20170906164417.2terp5ioelzglehq@pd.tnic> <56f022a2-e363-0524-68ba-c31950d96e0d@amd.com> <20170906181946.savnnahph7wtr76b@pd.tnic> <80046e97-9d4f-728f-337a-37969aac297e@oracle.com> <04defa6c-9cda-817c-c764-2911a5d45319@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <04defa6c-9cda-817c-c764-2911a5d45319@amd.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3530 Lines: 111 On Wed, Sep 06, 2017 at 07:26:40PM -0500, Brijesh Singh wrote: > 32-bit seems to be working well - thanks Thanks Boris and Brijesh for testing! --- From: Borislav Petkov The SME encryption mask is for masking 64-bit pagetable entries. It being an unsigned long works fine on X86_64 but on 32-bit builds in truncates bits leading to Xen guests crashing very early. And regardless, the whole SME mask handling shouldnt've leaked into 32-bit because SME is X86_64-only feature. So, first make the mask u64. And then, add trivial 32-bit versions of the __sme_* macros so that nothing happens there. Reported-and-tested-by: Boris Ostrovsky Tested-by: Brijesh Singh Signed-off-by: Borislav Petkov Acked-by: Tom Lendacky Fixes: 21729f81ce8a ("x86/mm: Provide general kernel support for memory encryption") --- arch/x86/include/asm/mem_encrypt.h | 4 ++-- arch/x86/mm/mem_encrypt.c | 2 +- include/linux/mem_encrypt.h | 13 +++++++++---- 3 files changed, 12 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index 8e618fcf1f7c..6a77c63540f7 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -21,7 +21,7 @@ #ifdef CONFIG_AMD_MEM_ENCRYPT -extern unsigned long sme_me_mask; +extern u64 sme_me_mask; void sme_encrypt_execute(unsigned long encrypted_kernel_vaddr, unsigned long decrypted_kernel_vaddr, @@ -49,7 +49,7 @@ void swiotlb_set_mem_attributes(void *vaddr, unsigned long size); #else /* !CONFIG_AMD_MEM_ENCRYPT */ -#define sme_me_mask 0UL +#define sme_me_mask 0ULL static inline void __init sme_early_encrypt(resource_size_t paddr, unsigned long size) { } diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 0fbd09269757..3fcc8e01683b 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -37,7 +37,7 @@ static char sme_cmdline_off[] __initdata = "off"; * reside in the .data section so as not to be zeroed out when the .bss * section is later cleared. */ -unsigned long sme_me_mask __section(.data) = 0; +u64 sme_me_mask __section(.data) = 0; EXPORT_SYMBOL_GPL(sme_me_mask); /* Buffer used for early in-place encryption by BSP, no locking needed */ diff --git a/include/linux/mem_encrypt.h b/include/linux/mem_encrypt.h index 1255f09f5e42..265a9cd21cb4 100644 --- a/include/linux/mem_encrypt.h +++ b/include/linux/mem_encrypt.h @@ -21,7 +21,7 @@ #else /* !CONFIG_ARCH_HAS_MEM_ENCRYPT */ -#define sme_me_mask 0UL +#define sme_me_mask 0ULL #endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */ @@ -30,18 +30,23 @@ static inline bool sme_active(void) return !!sme_me_mask; } -static inline unsigned long sme_get_me_mask(void) +static inline u64 sme_get_me_mask(void) { return sme_me_mask; } +#ifdef CONFIG_AMD_MEM_ENCRYPT /* * The __sme_set() and __sme_clr() macros are useful for adding or removing * the encryption mask from a value (e.g. when dealing with pagetable * entries). */ -#define __sme_set(x) ((unsigned long)(x) | sme_me_mask) -#define __sme_clr(x) ((unsigned long)(x) & ~sme_me_mask) +#define __sme_set(x) ((x) | sme_me_mask) +#define __sme_clr(x) ((x) & ~sme_me_mask) +#else +#define __sme_set(x) (x) +#define __sme_clr(x) (x) +#endif #endif /* __ASSEMBLY__ */ -- 2.13.0 -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.