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Shutemov" X-Patchwork-Id: 12915802 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E647DC43334 for ; Tue, 12 Jul 2022 23:13:38 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9D3599400E4; Tue, 12 Jul 2022 19:13:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 982E69400E3; Tue, 12 Jul 2022 19:13:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 823569400E2; Tue, 12 Jul 2022 19:13:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 70DFA9400E1 for ; Tue, 12 Jul 2022 19:13:32 -0400 (EDT) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay12.hostedemail.com (Postfix) with ESMTP id 2EC8D1208E6 for ; Tue, 12 Jul 2022 23:13:32 +0000 (UTC) X-FDA: 79680001464.01.1ADF747 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by imf21.hostedemail.com (Postfix) with ESMTP id 8B53D1C007C for ; Tue, 12 Jul 2022 23:13:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1657667611; x=1689203611; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=6kpq1VPBF3XlDpY7P9nLlIhIxMc1N9UleTXT2cgue9s=; b=jBKMjwZCXu/jKKYXXggynjoweS7LIuWOdWnVO2oRTSrlMD9dg8bCNjya LeC8bXYbbWTY0hbh0X63cVNUFzIE30G01Ftu2i8uVYN7wH3kAXGDNnUfX ogpejjGaIH1OhUxEBTCBqo6go91kmdx7dfE8uv1FC4f2ab+/8CvvMvbAe gCfzWc+jYvKNAsQwY3Z3P0vPizMGMmKYvTM49B9GqXXHJYIa2bHuxQSwL 1J77TGuZ6sZWr266F0d/+d/B2R2NzOL7ej/COpCaJa/VICLhs5jflaL5/ ocO0QIgijPrVzaYQo77WS5gNoTjPU4w0JnFPz7DawC1xLOy4+SY8fICeh w==; X-IronPort-AV: E=McAfee;i="6400,9594,10406"; a="286196176" X-IronPort-AV: E=Sophos;i="5.92,266,1650956400"; d="scan'208";a="286196176" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jul 2022 16:13:30 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.92,266,1650956400"; d="scan'208";a="722131606" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga004.jf.intel.com with ESMTP; 12 Jul 2022 16:13:26 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 4227A6CD; Wed, 13 Jul 2022 02:13:30 +0300 (EEST) From: "Kirill A. Shutemov" To: Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: x86@kernel.org, Kostya Serebryany , Andrey Ryabinin , Andrey Konovalov , Alexander Potapenko , Taras Madan , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv5 OPTIONAL 12/13] x86/mm: Extend LAM to support to LAM_U48 Date: Wed, 13 Jul 2022 02:13:27 +0300 Message-Id: <20220712231328.5294-13-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220712231328.5294-1-kirill.shutemov@linux.intel.com> References: <20220712231328.5294-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1657667611; a=rsa-sha256; cv=none; b=LjGocMQ/HaxdhvlDbVphS7QNV0RUCaaAzXpoUZLrYirU2EB78w+6BxBqmU1g1R+c3Cv5qb 6tH+Ia1ucKZpWk9205xhYoL+gGa0befdeD20+dBkhKF98InF9oRDHoM3WaAETmkwoiqipa urjW/bLw3+jvhlEm+TuIcLmq9ocU3Qk= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=jBKMjwZC; spf=none (imf21.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 134.134.136.65) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1657667611; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=9ucKyndM4WLt/vUK4/I4AyINLEfZmR1mDMwoFuS059E=; b=C64uA/MqgcX0obtNp4KxN5LX/wl5HQg3F5JSOSP1TWOKNVDi1PxFqa6AQRaumxF6iHUkOB U9+gr9fgQujzr1XHHjYj4VMIDt/w/76Yw2BwEt1k1VQJo49Lrm+2SRWG26lUyd5BWkXPpj vu/q3fb+h18chPxL4amhyKV97BbZs5o= X-Rspamd-Queue-Id: 8B53D1C007C Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=jBKMjwZC; spf=none (imf21.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 134.134.136.65) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=pass (policy=none) header.from=intel.com X-Rspamd-Server: rspam02 X-Rspam-User: X-Stat-Signature: 65b8g5fut6gsbf6nboqz9uy46356wwuc X-HE-Tag: 1657667611-319346 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: LAM_U48 allows to encode 15 bits of tags into address. 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 other 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/process_64.c | 23 +++++++++++++++++++++++ arch/x86/kernel/sys_x86_64.c | 5 +++-- arch/x86/mm/hugetlbpage.c | 6 ++++-- arch/x86/mm/mmap.c | 10 +++++++++- 6 files changed, 54 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index cb0ff1055ab1..4df13497a770 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -317,7 +317,8 @@ 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 b0e9ea23758b..3736f41948e9 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -263,6 +263,19 @@ 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 above 47-bit for tags */ + return mm->context.lam_cr3_mask != X86_CR3_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/process_64.c b/arch/x86/kernel/process_64.c index 82a19168bfa4..cfa2e42a135a 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -761,6 +761,16 @@ static void enable_lam_func(void *mm) set_tlbstate_cr3_lam_mask(lam_mask); } +static bool lam_u48_allowed(void) +{ + struct mm_struct *mm = current->mm; + + if (!full_va_allowed(mm)) + return true; + + return find_vma(mm, DEFAULT_MAP_WINDOW) == NULL; +} + static int prctl_enable_tagged_addr(struct mm_struct *mm, unsigned long nr_bits) { int ret = 0; @@ -768,6 +778,10 @@ static int prctl_enable_tagged_addr(struct mm_struct *mm, unsigned long nr_bits) if (!cpu_feature_enabled(X86_FEATURE_LAM)) return -ENODEV; + /* lam_u48_allowed() requires mmap_lock */ + if (mmap_write_lock_killable(mm)) + return -EINTR; + mutex_lock(&mm->context.lock); /* Already enabled? */ @@ -782,6 +796,14 @@ static int prctl_enable_tagged_addr(struct mm_struct *mm, unsigned long nr_bits) } else if (nr_bits <= 6) { mm->context.lam_cr3_mask = X86_CR3_LAM_U57; mm->context.untag_mask = ~GENMASK(62, 57); + } else if (nr_bits <= 15) { + if (!lam_u48_allowed()) { + ret = -EBUSY; + goto out; + } + + mm->context.lam_cr3_mask = X86_CR3_LAM_U48; + mm->context.untag_mask = ~GENMASK(62, 48); } else { ret = -EINVAL; goto out; @@ -793,6 +815,7 @@ static int prctl_enable_tagged_addr(struct mm_struct *mm, unsigned long nr_bits) on_each_cpu_mask(mm_cpumask(mm), enable_lam_func, mm, true); out: mutex_unlock(&mm->context.lock); + mmap_write_unlock(mm); return ret; } diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index 8cc653ffdccd..5ea6aaed89ba 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. @@ -182,7 +183,7 @@ 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); @@ -203,7 +204,7 @@ 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..aa0086722a38 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; } @@ -170,6 +173,7 @@ const char *arch_vma_name(struct vm_area_struct *vma) /** * mmap_address_hint_valid - Validate the address hint of mmap + * @mm: Address space * @addr: Address hint * @len: Mapping length * @@ -206,11 +210,15 @@ 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); }