From: Joerg Roedel <jroe...@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 <jroe...@suse.de> --- arch/x86/include/asm/pgtable_32_types.h | 2 ++ arch/x86/include/asm/pgtable_64_types.h | 2 ++ arch/x86/kernel/ldt.c | 2 +- 3 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm/pgtable_32_types.h index eb2e97a..02bd445 100644 --- a/arch/x86/include/asm/pgtable_32_types.h +++ b/arch/x86/include/asm/pgtable_32_types.h @@ -51,6 +51,8 @@ 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 e57003a..15188baa 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -90,12 +90,14 @@ typedef struct { pteval_t pte; } pte_t; # define __VMEMMAP_BASE _AC(0xffd4000000000000, UL) # define LDT_PGD_ENTRY _AC(-112, UL) # define LDT_BASE_ADDR (LDT_PGD_ENTRY << PGDIR_SHIFT) +#define LDT_END_ADDR (LDT_BASE_ADDR + PGDIR_SIZE) #else # define VMALLOC_SIZE_TB _AC(32, UL) # define __VMALLOC_BASE _AC(0xffffc90000000000, UL) # define __VMEMMAP_BASE _AC(0xffffea0000000000, UL) # define LDT_PGD_ENTRY _AC(-3, UL) # define LDT_BASE_ADDR (LDT_PGD_ENTRY << PGDIR_SHIFT) +#define LDT_END_ADDR (LDT_BASE_ADDR + PGDIR_SIZE) #endif #ifdef CONFIG_RANDOMIZE_MEMORY diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c index 26d713e..f3c2fbf 100644 --- a/arch/x86/kernel/ldt.c +++ b/arch/x86/kernel/ldt.c @@ -202,7 +202,7 @@ 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