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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23B44C433F5 for ; Wed, 11 May 2022 02:31:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241564AbiEKCa4 (ORCPT ); Tue, 10 May 2022 22:30:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241287AbiEKC3u (ORCPT ); Tue, 10 May 2022 22:29:50 -0400 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C38A121A961 for ; Tue, 10 May 2022 19:29:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1652236188; x=1683772188; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=yh4/dFHOtWSE9iF+GUg2XMGu0/7JiKaWrQ/zWPdOw6Y=; b=EBDK8770Tn3fCw36mY697BFKERR1p3uKyqvE89dKNAnCawo+6pnvgLI3 shgKwcNAPP1Cr1OS//0ZrB/SPpJSZpz02lyNLUdAmQUJSj6byvptkq6yM Q8c1dIWbzEzgxL14754Hy4iwzau4FlpivtQqz+O1XHcQAdsE+e8B9GuUq BVPVb3ly37l05/1qlsdS6mjfFcwqzGhBAAB4MBOj7flhpexmm08ww34Fd +AuyFQ1iOy5FjqM4yWznYTLfBeCRibL1YJo2hRBppu/KgX0ZTI0Z7Zggw KIlJ6A6AnmpCxyELuP88WYUFNHRvFfbXW1nlNTVGeiof9QcluG5XjznqM g==; X-IronPort-AV: E=McAfee;i="6400,9594,10343"; a="330158673" X-IronPort-AV: E=Sophos;i="5.91,215,1647327600"; d="scan'208";a="330158673" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 May 2022 19:29:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.91,215,1647327600"; d="scan'208";a="711294411" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga001.fm.intel.com with ESMTP; 10 May 2022 19:29:40 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 5EA78630; Wed, 11 May 2022 05:28:01 +0300 (EEST) From: "Kirill A. Shutemov" To: Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: x86@kernel.org, Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [RFCv2 08/10] x86/mm: Make LAM_U48 and mappings above 47-bits mutually exclusive Date: Wed, 11 May 2022 05:27:49 +0300 Message-Id: <20220511022751.65540-10-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220511022751.65540-1-kirill.shutemov@linux.intel.com> References: <20220511022751.65540-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org LAM_U48 steals bits above 47-bit for tags and makes it impossible for userspace to use full address space on 5-level paging machine. Make these features mutually exclusive: whichever gets enabled first blocks the othe one. Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm/elf.h | 3 ++- arch/x86/include/asm/mmu_context.h | 13 +++++++++++++ arch/x86/kernel/sys_x86_64.c | 5 +++-- arch/x86/mm/hugetlbpage.c | 6 ++++-- arch/x86/mm/mmap.c | 9 ++++++++- 5 files changed, 30 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 29fea180a665..53b96b0c8cc3 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -328,7 +328,8 @@ static inline int mmap_is_ia32(void) extern unsigned long task_size_32bit(void); extern unsigned long task_size_64bit(int full_addr_space); extern unsigned long get_mmap_base(int is_legacy); -extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len); +extern bool mmap_address_hint_valid(struct mm_struct *mm, + unsigned long addr, unsigned long len); extern unsigned long get_sigframe_size(void); #ifdef CONFIG_X86_32 diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 27516046117a..c8a6d80dfec3 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -218,6 +218,19 @@ static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, unsigned long __get_current_cr3_fast(void); +#ifdef CONFIG_X86_5LEVEL +static inline bool full_va_allowed(struct mm_struct *mm) +{ + /* LAM_U48 steals VA bits abouve 47-bit for tags */ + return mm->context.lam != LAM_U48; +} +#else +static inline bool full_va_allowed(struct mm_struct *mm) +{ + return false; +} +#endif + #include #endif /* _ASM_X86_MMU_CONTEXT_H */ diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index 660b78827638..4526e8fadfd2 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -21,6 +21,7 @@ #include #include +#include /* * Align a virtual address to avoid aliasing in the I$ on AMD F15h. @@ -185,7 +186,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, /* requesting a specific address */ if (addr) { addr &= PAGE_MASK; - if (!mmap_address_hint_valid(addr, len)) + if (!mmap_address_hint_valid(mm, addr, len)) goto get_unmapped_area; vma = find_vma(mm, addr); @@ -206,7 +207,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, * !in_32bit_syscall() check to avoid high addresses for x32 * (and make it no op on native i386). */ - if (addr > DEFAULT_MAP_WINDOW && !in_32bit_syscall()) + if (addr > DEFAULT_MAP_WINDOW && !in_32bit_syscall() && full_va_allowed(mm)) info.high_limit += TASK_SIZE_MAX - DEFAULT_MAP_WINDOW; info.align_mask = 0; diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index a0d023cb4292..9fdc8db42365 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -18,6 +18,7 @@ #include #include #include +#include #if 0 /* This is just for testing */ struct page * @@ -103,6 +104,7 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, unsigned long pgoff, unsigned long flags) { struct hstate *h = hstate_file(file); + struct mm_struct *mm = current->mm; struct vm_unmapped_area_info info; info.flags = VM_UNMAPPED_AREA_TOPDOWN; @@ -114,7 +116,7 @@ static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file, * If hint address is above DEFAULT_MAP_WINDOW, look for unmapped area * in the full address space. */ - if (addr > DEFAULT_MAP_WINDOW && !in_32bit_syscall()) + if (addr > DEFAULT_MAP_WINDOW && !in_32bit_syscall() && full_va_allowed(mm)) info.high_limit += TASK_SIZE_MAX - DEFAULT_MAP_WINDOW; info.align_mask = PAGE_MASK & ~huge_page_mask(h); @@ -161,7 +163,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, if (addr) { addr &= huge_page_mask(h); - if (!mmap_address_hint_valid(addr, len)) + if (!mmap_address_hint_valid(mm, addr, len)) goto get_unmapped_area; vma = find_vma(mm, addr); diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c index c90c20904a60..f9ca824729de 100644 --- a/arch/x86/mm/mmap.c +++ b/arch/x86/mm/mmap.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "physaddr.h" @@ -35,6 +36,8 @@ unsigned long task_size_32bit(void) unsigned long task_size_64bit(int full_addr_space) { + if (!full_va_allowed(current->mm)) + return DEFAULT_MAP_WINDOW; return full_addr_space ? TASK_SIZE_MAX : DEFAULT_MAP_WINDOW; } @@ -206,11 +209,15 @@ const char *arch_vma_name(struct vm_area_struct *vma) * the failure of such a fixed mapping request, so the restriction is not * applied. */ -bool mmap_address_hint_valid(unsigned long addr, unsigned long len) +bool mmap_address_hint_valid(struct mm_struct *mm, + unsigned long addr, unsigned long len) { if (TASK_SIZE - len < addr) return false; + if (addr + len > DEFAULT_MAP_WINDOW && !full_va_allowed(mm)) + return false; + return (addr > DEFAULT_MAP_WINDOW) == (addr + len > DEFAULT_MAP_WINDOW); } -- 2.35.1