diff mbox

[34/39] x86/ldt: Define LDT_END_ADDR

Message ID 1531308586-29340-35-git-send-email-joro@8bytes.org (mailing list archive)
State New, archived
Headers show

Commit Message

Joerg Roedel July 11, 2018, 11:29 a.m. UTC 
From: Joerg Roedel <jroedel@suse.de>

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 <jroedel@suse.de>
---
 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(-)

Comments

Andy Lutomirski July 13, 2018, 5:29 p.m. UTC | #1 
On Wed, Jul 11, 2018 at 4:29 AM, Joerg Roedel <joro@8bytes.org> wrote:
> From: Joerg Roedel <jroedel@suse.de>
>
> 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.
>

Reviewed-by: Andy Lutomirski <luto@kernel.org>
diff mbox

Patch

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..e921b3d 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;