diff options
Diffstat (limited to 'arch/x86/include/asm/pgalloc.h')
| -rw-r--r-- | arch/x86/include/asm/pgalloc.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h index b2d0cd8288aa..aff42e1da6ee 100644 --- a/arch/x86/include/asm/pgalloc.h +++ b/arch/x86/include/asm/pgalloc.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_PGALLOC_H #define _ASM_X86_PGALLOC_H @@ -29,6 +30,17 @@ static inline void paravirt_release_p4d(unsigned long pfn) {} */ extern gfp_t __userpte_alloc_gfp; +#ifdef CONFIG_PAGE_TABLE_ISOLATION +/* + * Instead of one PGD, we acquire two PGDs. Being order-1, it is + * both 8k in size and 8k-aligned. That lets us just flip bit 12 + * in a pointer to swap between the two 4k halves. + */ +#define PGD_ALLOCATION_ORDER 1 +#else +#define PGD_ALLOCATION_ORDER 0 +#endif + /* * Allocate and free page tables. */ |