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Shutemov" X-Patchwork-Id: 10461105 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 15764601A0 for ; Tue, 12 Jun 2018 20:07:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0A2F5274D0 for ; Tue, 12 Jun 2018 20:07:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F2AA828AEC; Tue, 12 Jun 2018 20:07:36 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 42162274D0 for ; Tue, 12 Jun 2018 20:07:36 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8BA2F6B0005; Tue, 12 Jun 2018 16:07:34 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 869CB6B0006; Tue, 12 Jun 2018 16:07:34 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 77FD76B0007; Tue, 12 Jun 2018 16:07:34 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-pg0-f72.google.com (mail-pg0-f72.google.com [74.125.83.72]) by kanga.kvack.org (Postfix) with ESMTP id 38EEA6B0005 for ; Tue, 12 Jun 2018 16:07:34 -0400 (EDT) Received: by mail-pg0-f72.google.com with SMTP id e2-v6so48496pgq.4 for ; Tue, 12 Jun 2018 13:07:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:date:from:to :cc:subject:message-id:references:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=tB5z1dley1JTQp430Xszr82wX/FAZdbH8KNAujtIOTA=; b=mnkCbVQTjoevaHNiNd+4wU4Rqz+5GwVEtrYq01nYaai1eZDxFqIDpAdBpKZpvmKEYl piMD+Ozp7ITGWq5ut14TAXMcGsG6ptb66hXwUmHqJmzXLWZE7Sc8AvaZe5+SV6nMHWej B4y+Z0Owu4l/JjQLi/ehB3kibtj3EMN3+28peaomDMM+qBvz8g+9AkZzFcNua7SU0gLJ fWi8LDng3WvqkpWdzJUTwGKH5VgqYl5QzImRVgSJvenvZdx0+7a+xWCMEfhyUn38YRne ur62XZWKraBnmIT6tZHwPOOOvCjmCut4+CENqgDaEvo73M2BSL1e9iO3yAomYP58pbDt PPNQ== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of kirill.shutemov@linux.intel.com designates 192.55.52.151 as permitted sender) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com X-Gm-Message-State: APt69E3OeW1DZaa9I9w8OfYw8sQt6sgt+Qy7MBHcMY/zzOMKA86e9ShV WOtyhgkRzHoOcfMs+vuSDPcD5Cgex9Nnje+1Nur605uxXYANtiAzHEhB6cy+mJt7jP3MnGku1DE LunOS3lSGtdQ5etucdYvBV4RQGbBq3iOeKZcGo3rRvuPbRII4EzrN0mvkhsj6GCLrrQ== X-Received: by 2002:aa7:85c9:: with SMTP id z9-v6mr1815572pfn.55.1528834053864; Tue, 12 Jun 2018 13:07:33 -0700 (PDT) X-Google-Smtp-Source: ADUXVKLN5zTKSFVNoi/hqzfsD0A9m/SW5l4IQIARTL67BnvbulysfFkdxYE+mVNmHWWdulHSPife X-Received: by 2002:aa7:85c9:: with SMTP id z9-v6mr1815511pfn.55.1528834052605; Tue, 12 Jun 2018 13:07:32 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1528834052; cv=none; d=google.com; s=arc-20160816; b=xdp5q8CRjSapbd1A4140VV+/cqLI4q98VuM6cTQHE6tTaSkTjvMHXRFOIkXTiN5Tpd A29C0rPqgIjHojsVJNwZ379s19aEhft+8tlHU84tz0+eKqGTED1JgxgcgN/qiF7dy8ae 64KbrDQwKEpGVPbeJjhjniuMdXo9CUK8GvP+WWmmrrnY/lJR/Ql5JZwx1ACs4rqhgnFr UcW1eN9OeQR1pW0v8+tY8lGy5nwGNX3pZEUH/9gPiOQLYHxcaH+mEXEBqIgnkCdu8MHE W007hyqOug4qb55i7WlQMe56iN6LrYC6PnZklPOL74tGj1r4Q/lTuRZrfBqtDIN8udiv /O1w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-transfer-encoding :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:arc-authentication-results; bh=tB5z1dley1JTQp430Xszr82wX/FAZdbH8KNAujtIOTA=; b=cAG9ZHhlRWWzfjYM11X+bVMrMpOhv110HljReDh+18GpcZ2++YDyaWC5w5UeyUftsz NIx1REsjpj7U8KgGZ4MS/yQ8jF7pKI3uttZVnx3SvVXPHiHoUXo7BYpXu2r01P7azIug Sdee2MvPb/Lh5QbwqUuZFmXl6qKvOYGqN7/BQKXbY6vwslHAd0m8d4Klqr6T4uOWiOWE oEbClXK5kTXLAVoqQJWkNLuItl51Jnxzw/aGDTzdHCjbz8PDRD78i4Totajhb7Ye6vRP 2iQa3BZPCZKSEB3OYOlCl/rj1c1+Z7RFjtTyDJPnzFmbF9bQx91hwEDXGxrAsngdtUw9 SugA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of kirill.shutemov@linux.intel.com designates 192.55.52.151 as permitted sender) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: from mga17.intel.com (mga17.intel.com. [192.55.52.151]) by mx.google.com with ESMTPS id s7-v6si758943pgq.230.2018.06.12.13.07.32 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 12 Jun 2018 13:07:32 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of kirill.shutemov@linux.intel.com designates 192.55.52.151 as permitted sender) client-ip=192.55.52.151; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of kirill.shutemov@linux.intel.com designates 192.55.52.151 as permitted sender) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Jun 2018 13:07:31 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,216,1526367600"; d="scan'208";a="236883506" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga006.fm.intel.com with ESMTP; 12 Jun 2018 13:07:28 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 58CF8B7; Tue, 12 Jun 2018 23:07:28 +0300 (EEST) Date: Tue, 12 Jun 2018 23:07:28 +0300 From: "Kirill A. Shutemov" To: Mika =?iso-8859-1?Q?Penttil=E4?= Cc: Ingo Molnar , x86@kernel.org, Thomas Gleixner , "H. Peter Anvin" , Tom Lendacky , Dave Hansen , Kai Huang , Jacob Pan , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCHv3 14/17] x86/mm: Introduce direct_mapping_size Message-ID: <20180612200728.h5oxfhzb4mijjwrr@black.fi.intel.com> References: <20180612143915.68065-1-kirill.shutemov@linux.intel.com> <20180612143915.68065-15-kirill.shutemov@linux.intel.com> <030253cc-2db5-8faf-15ef-bb7828c5f624@nextfour.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <030253cc-2db5-8faf-15ef-bb7828c5f624@nextfour.com> User-Agent: NeoMutt/20170714-126-deb55f (1.8.3) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: X-Virus-Scanned: ClamAV using ClamSMTP On Tue, Jun 12, 2018 at 02:58:38PM +0000, Mika Penttilä wrote: > > > On 12.06.2018 17:39, Kirill A. Shutemov wrote: > > Kernel need to have a way to access encrypted memory. We are going to > > use per-KeyID direct mapping to facilitate the access with minimal > > overhead. > > > > Direct mapping for each KeyID will be put next to each other in the > > virtual address space. We need to have a way to find boundaries of > > direct mapping for particular KeyID. > > > > The new variable direct_mapping_size specifies the size of direct > > mapping. With the value, it's trivial to find direct mapping for > > KeyID-N: PAGE_OFFSET + N * direct_mapping_size. > > > > Size of direct mapping is calculated during KASLR setup. If KALSR is > > disable it happens during MKTME initialization. > > > > Signed-off-by: Kirill A. Shutemov > > --- > > arch/x86/include/asm/mktme.h | 2 ++ > > arch/x86/include/asm/page_64.h | 1 + > > arch/x86/kernel/head64.c | 2 ++ > > arch/x86/mm/kaslr.c | 21 ++++++++++++--- > > arch/x86/mm/mktme.c | 48 ++++++++++++++++++++++++++++++++++ > > 5 files changed, 71 insertions(+), 3 deletions(-) > > > > diff --git a/arch/x86/include/asm/mktme.h b/arch/x86/include/asm/mktme.h > > index 9363b989a021..3bf481fe3f56 100644 > > --- a/arch/x86/include/asm/mktme.h > > +++ b/arch/x86/include/asm/mktme.h > > @@ -40,6 +40,8 @@ int page_keyid(const struct page *page); > > > > void mktme_disable(void); > > > > +void setup_direct_mapping_size(void); > > + > > #else > > #define mktme_keyid_mask ((phys_addr_t)0) > > #define mktme_nr_keyids 0 > > diff --git a/arch/x86/include/asm/page_64.h b/arch/x86/include/asm/page_64.h > > index 939b1cff4a7b..53c32af895ab 100644 > > --- a/arch/x86/include/asm/page_64.h > > +++ b/arch/x86/include/asm/page_64.h > > @@ -14,6 +14,7 @@ extern unsigned long phys_base; > > extern unsigned long page_offset_base; > > extern unsigned long vmalloc_base; > > extern unsigned long vmemmap_base; > > +extern unsigned long direct_mapping_size; > > > > static inline unsigned long __phys_addr_nodebug(unsigned long x) > > { > > diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c > > index a21d6ace648e..b6175376b2e1 100644 > > --- a/arch/x86/kernel/head64.c > > +++ b/arch/x86/kernel/head64.c > > @@ -59,6 +59,8 @@ EXPORT_SYMBOL(vmalloc_base); > > unsigned long vmemmap_base __ro_after_init = __VMEMMAP_BASE_L4; > > EXPORT_SYMBOL(vmemmap_base); > > #endif > > +unsigned long direct_mapping_size __ro_after_init = -1UL; > > +EXPORT_SYMBOL(direct_mapping_size); > > > > #define __head __section(.head.text) > > > > diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c > > index 4408cd9a3bef..3d8ef8cb97e1 100644 > > --- a/arch/x86/mm/kaslr.c > > +++ b/arch/x86/mm/kaslr.c > > @@ -69,6 +69,15 @@ static inline bool kaslr_memory_enabled(void) > > return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN); > > } > > > > +#ifndef CONFIG_X86_INTEL_MKTME > > +static void __init setup_direct_mapping_size(void) > > +{ > > + direct_mapping_size = max_pfn << PAGE_SHIFT; > > + direct_mapping_size = round_up(direct_mapping_size, 1UL << TB_SHIFT); > > + direct_mapping_size += (1UL << TB_SHIFT) * CONFIG_MEMORY_PHYSICAL_PADDING; > > +} > > +#endif > > + > > /* Initialize base and padding for each memory region randomized with KASLR */ > > void __init kernel_randomize_memory(void) > > { > > @@ -93,7 +102,11 @@ void __init kernel_randomize_memory(void) > > if (!kaslr_memory_enabled()) > > return; > > > > - kaslr_regions[0].size_tb = 1 << (__PHYSICAL_MASK_SHIFT - TB_SHIFT); > > + /* > > + * Upper limit for direct mapping size is 1/4 of whole virtual > > + * address space > > or 1/2? 1/2 of kernel address space or 1/4 of whole address space. > > > + */ > > + kaslr_regions[0].size_tb = 1 << (__VIRTUAL_MASK_SHIFT - 1 - TB_SHIFT); > > > > > kaslr_regions[1].size_tb = VMALLOC_SIZE_TB; > > > > /* > > @@ -101,8 +114,10 @@ void __init kernel_randomize_memory(void) > > * add padding if needed (especially for memory hotplug support). > > */ > > BUG_ON(kaslr_regions[0].base != &page_offset_base); > > - memory_tb = DIV_ROUND_UP(max_pfn << PAGE_SHIFT, 1UL << TB_SHIFT) + > > - CONFIG_MEMORY_PHYSICAL_PADDING; > > + > > + setup_direct_mapping_size(); > > + > > + memory_tb = direct_mapping_size * mktme_nr_keyids + 1; > > parenthesis ? > > memory_tb = direct_mapping_size * (mktme_nr_keyids + 1); Ouch. Thanks for noticing this. > > > > /* Adapt phyiscal memory region size based on available memory */ > > if (memory_tb < kaslr_regions[0].size_tb) > > diff --git a/arch/x86/mm/mktme.c b/arch/x86/mm/mktme.c > > index 43a44f0f2a2d..3e5322bf035e 100644 > > --- a/arch/x86/mm/mktme.c > > +++ b/arch/x86/mm/mktme.c > > @@ -89,3 +89,51 @@ static bool need_page_mktme(void) > > struct page_ext_operations page_mktme_ops = { > > .need = need_page_mktme, > > }; > > + > > +void __init setup_direct_mapping_size(void) > > +{ > > + unsigned long available_va; > > + > > + /* 1/4 of virtual address space is didicated for direct mapping */ > > + available_va = 1UL << (__VIRTUAL_MASK_SHIFT - 1); > > + > > + /* How much memory the systrem has? */ > > + direct_mapping_size = max_pfn << PAGE_SHIFT; > > + direct_mapping_size = round_up(direct_mapping_size, 1UL << 40); > > + > > + if (mktme_status != MKTME_ENUMERATED) > > + goto out; > > + > > + /* > > + * Not enough virtual address space to address all physical memory with > > + * MKTME enabled. Even without padding. > > + * > > + * Disable MKTME instead. > > + */ > > + if (direct_mapping_size > available_va / mktme_nr_keyids + 1) { > > parenthesis again? > > if (direct_mapping_size > available_va / (mktme_nr_keyids + 1)) { Yeah... :/ Here's fixup. diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 3d8ef8cb97e1..ef437c8d5f34 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -103,8 +103,8 @@ void __init kernel_randomize_memory(void) return; /* - * Upper limit for direct mapping size is 1/4 of whole virtual - * address space + * Upper limit for direct mapping size is half of kernel address + * space. */ kaslr_regions[0].size_tb = 1 << (__VIRTUAL_MASK_SHIFT - 1 - TB_SHIFT); kaslr_regions[1].size_tb = VMALLOC_SIZE_TB; @@ -117,7 +117,7 @@ void __init kernel_randomize_memory(void) setup_direct_mapping_size(); - memory_tb = direct_mapping_size * mktme_nr_keyids + 1; + memory_tb = direct_mapping_size * (mktme_nr_keyids + 1); /* Adapt phyiscal memory region size based on available memory */ if (memory_tb < kaslr_regions[0].size_tb) diff --git a/arch/x86/mm/mktme.c b/arch/x86/mm/mktme.c index 3e5322bf035e..70f6eff093d8 100644 --- a/arch/x86/mm/mktme.c +++ b/arch/x86/mm/mktme.c @@ -110,7 +110,7 @@ void __init setup_direct_mapping_size(void) * * Disable MKTME instead. */ - if (direct_mapping_size > available_va / mktme_nr_keyids + 1) { + if (direct_mapping_size > available_va / (mktme_nr_keyids + 1)) { pr_err("x86/mktme: Disabled. Not enough virtual address space\n"); pr_err("x86/mktme: Consider switching to 5-level paging\n"); mktme_disable();