From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id AC4FC6B028B for ; Tue, 15 Nov 2016 10:33:42 -0500 (EST) Received: by mail-wm0-f69.google.com with SMTP id g23so2209066wme.4 for ; Tue, 15 Nov 2016 07:33:42 -0800 (PST) Received: from mail.skyhub.de (mail.skyhub.de. [2a01:4f8:120:8448::d00d]) by mx.google.com with ESMTP id qf11si28889047wjb.173.2016.11.15.07.33.41 for ; Tue, 15 Nov 2016 07:33:41 -0800 (PST) Date: Tue, 15 Nov 2016 16:33:39 +0100 From: Borislav Petkov Subject: Re: [RFC PATCH v3 04/20] x86: Handle reduction in physical address size with SME Message-ID: <20161115153338.a2cxmatnpqcgiaiy@pd.tnic> References: <20161110003426.3280.2999.stgit@tlendack-t1.amdoffice.net> <20161110003513.3280.12104.stgit@tlendack-t1.amdoffice.net> <20161115121035.GD24857@8bytes.org> <20161115121456.f4slpk4i2jl3e2ke@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Tom Lendacky Cc: Joerg Roedel , linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Rik van Riel , Radim =?utf-8?B?S3LEjW3DocWZ?= , Arnd Bergmann , Jonathan Corbet , Matt Fleming , Konrad Rzeszutek Wilk , Paolo Bonzini , Larry Woodman , Ingo Molnar , Andy Lutomirski , "H. Peter Anvin" , Andrey Ryabinin , Alexander Potapenko , Thomas Gleixner , Dmitry Vyukov On Tue, Nov 15, 2016 at 08:40:05AM -0600, Tom Lendacky wrote: > The feature may be present and enabled even if it is not currently > active. In other words, the SYS_CFG MSR bit could be set but we aren't > actually using encryption (sme_me_mask is 0). As long as the SYS_CFG > MSR bit is set we need to take into account the physical reduction in > address space. But later in the series I see sme_early_mem_enc() which tests exactly that mask. And in patch 12 you have: + /* + * If memory encryption is active, the trampoline area will need to + * be in un-encrypted memory in order to bring up other processors + * successfully. + */ + sme_early_mem_dec(__pa(base), size); + sme_set_mem_unenc(base, size); What's up? IOW, it all sounds to me like you want to have an sme_active() helper and use it everywhere. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org