From 8195d869d118bc30bf0be8d0c5d8849d6f58529b Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 18 Jul 2018 11:41:11 +0200 Subject: [PATCH] x86/ldt: Define LDT_END_ADDR It marks the end of the address-space range reserved for the LDT. The LDT-code will use it when unmapping the LDT for user-space. Signed-off-by: Joerg Roedel Signed-off-by: Thomas Gleixner Tested-by: Pavel Machek Cc: "H . Peter Anvin" Cc: linux-mm@kvack.org Cc: Linus Torvalds Cc: Andy Lutomirski Cc: Dave Hansen Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Peter Zijlstra Cc: Borislav Petkov Cc: Jiri Kosina Cc: Boris Ostrovsky Cc: Brian Gerst Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Cc: Andrea Arcangeli Cc: Waiman Long Cc: "David H . Gutteridge" Cc: joro@8bytes.org Link: https://lkml.kernel.org/r/1531906876-13451-35-git-send-email-joro@8bytes.org --- arch/x86/include/asm/pgtable_32_types.h | 2 ++ arch/x86/include/asm/pgtable_64_types.h | 1 + arch/x86/kernel/ldt.c | 2 +- 3 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm/pgtable_32_types.h index 7297810..b0bc0ff 100644 --- a/arch/x86/include/asm/pgtable_32_types.h +++ b/arch/x86/include/asm/pgtable_32_types.h @@ -53,6 +53,8 @@ extern bool __vmalloc_start_set; /* set once high_memory is set */ #define LDT_BASE_ADDR \ ((CPU_ENTRY_AREA_BASE - PAGE_SIZE) & PMD_MASK) +#define LDT_END_ADDR (LDT_BASE_ADDR + PMD_SIZE) + #define PKMAP_BASE \ ((LDT_BASE_ADDR - PAGE_SIZE) & PMD_MASK) diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 066e0ab..04edd2d 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -115,6 +115,7 @@ extern unsigned int ptrs_per_p4d; #define LDT_PGD_ENTRY_L5 -112UL #define LDT_PGD_ENTRY (pgtable_l5_enabled() ? LDT_PGD_ENTRY_L5 : LDT_PGD_ENTRY_L4) #define LDT_BASE_ADDR (LDT_PGD_ENTRY << PGDIR_SHIFT) +#define LDT_END_ADDR (LDT_BASE_ADDR + PGDIR_SIZE) #define __VMALLOC_BASE_L4 0xffffc90000000000UL #define __VMALLOC_BASE_L5 0xffa0000000000000UL diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c index c9b1402..e921b3d4 100644 --- a/arch/x86/kernel/ldt.c +++ b/arch/x86/kernel/ldt.c @@ -206,7 +206,7 @@ static void free_ldt_pgtables(struct mm_struct *mm) #ifdef CONFIG_PAGE_TABLE_ISOLATION struct mmu_gather tlb; unsigned long start = LDT_BASE_ADDR; - unsigned long end = start + (1UL << PGDIR_SHIFT); + unsigned long end = LDT_END_ADDR; if (!static_cpu_has(X86_FEATURE_PTI)) return; -- 2.7.4