| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _ASM_X86_PAGE_64_DEFS_H |
| #define _ASM_X86_PAGE_64_DEFS_H |
| |
| #ifndef __ASSEMBLY__ |
| #include <asm/kaslr.h> |
| #endif |
| |
| #ifdef CONFIG_KASAN |
| #define KASAN_STACK_ORDER 1 |
| #else |
| #define KASAN_STACK_ORDER 0 |
| #endif |
| |
| #define THREAD_SIZE_ORDER (2 + KASAN_STACK_ORDER) |
| #define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER) |
| |
| #define EXCEPTION_STACK_ORDER (0 + KASAN_STACK_ORDER) |
| #define EXCEPTION_STKSZ (PAGE_SIZE << EXCEPTION_STACK_ORDER) |
| |
| #define IRQ_STACK_ORDER (2 + KASAN_STACK_ORDER) |
| #define IRQ_STACK_SIZE (PAGE_SIZE << IRQ_STACK_ORDER) |
| |
| /* |
| * The index for the tss.ist[] array. The hardware limit is 7 entries. |
| */ |
| #define IST_INDEX_DF 0 |
| #define IST_INDEX_NMI 1 |
| #define IST_INDEX_DB 2 |
| #define IST_INDEX_MCE 3 |
| #define IST_INDEX_VC 4 |
| |
| /* |
| * Set __PAGE_OFFSET to the most negative possible address + |
| * PGDIR_SIZE*17 (pgd slot 273). |
| * |
| * The gap is to allow a space for LDT remap for PTI (1 pgd slot) and space for |
| * a hypervisor (16 slots). Choosing 16 slots for a hypervisor is arbitrary, |
| * but it's what Xen requires. |
| */ |
| #define __PAGE_OFFSET_BASE_L5 _AC(0xff11000000000000, UL) |
| #define __PAGE_OFFSET_BASE_L4 _AC(0xffff888000000000, UL) |
| |
| #ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT |
| #define __PAGE_OFFSET page_offset_base |
| #else |
| #define __PAGE_OFFSET __PAGE_OFFSET_BASE_L4 |
| #endif /* CONFIG_DYNAMIC_MEMORY_LAYOUT */ |
| |
| #define __START_KERNEL_map _AC(0xffffffff80000000, UL) |
| |
| /* See Documentation/x86/x86_64/mm.rst for a description of the memory map. */ |
| |
| #define __PHYSICAL_MASK_SHIFT 52 |
| |
| #ifdef CONFIG_X86_5LEVEL |
| #define __VIRTUAL_MASK_SHIFT (pgtable_l5_enabled() ? 56 : 47) |
| #else |
| #define __VIRTUAL_MASK_SHIFT 47 |
| #endif |
| |
| /* |
| * User space process size. This is the first address outside the user range. |
| * There are a few constraints that determine this: |
| * |
| * On Intel CPUs, if a SYSCALL instruction is at the highest canonical |
| * address, then that syscall will enter the kernel with a |
| * non-canonical return address, and SYSRET will explode dangerously. |
| * We avoid this particular problem by preventing anything executable |
| * from being mapped at the maximum canonical address. |
| * |
| * On AMD CPUs in the Ryzen family, there's a nasty bug in which the |
| * CPUs malfunction if they execute code from the highest canonical page. |
| * They'll speculate right off the end of the canonical space, and |
| * bad things happen. This is worked around in the same way as the |
| * Intel problem. |
| * |
| * With page table isolation enabled, we map the LDT in ... [stay tuned] |
| */ |
| #define TASK_SIZE_MAX ((_AC(1,UL) << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE) |
| |
| #define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE) |
| |
| /* This decides where the kernel will search for a free chunk of vm |
| * space during mmap's. |
| */ |
| #define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \ |
| 0xc0000000 : 0xFFFFe000) |
| |
| #define TASK_SIZE_LOW (test_thread_flag(TIF_ADDR32) ? \ |
| IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW) |
| #define TASK_SIZE (test_thread_flag(TIF_ADDR32) ? \ |
| IA32_PAGE_OFFSET : TASK_SIZE_MAX) |
| #define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \ |
| IA32_PAGE_OFFSET : TASK_SIZE_MAX) |
| |
| #define STACK_TOP TASK_SIZE_LOW |
| #define STACK_TOP_MAX TASK_SIZE_MAX |
| |
| /* |
| * In spite of the name, KERNEL_IMAGE_SIZE is a limit on the maximum virtual |
| * address for the kernel image, rather than the limit on the size itself. |
| * This can be at most 1 GiB, due to the fixmap living in the next 1 GiB (see |
| * level2_kernel_pgt in arch/x86/kernel/head_64.S). |
| * |
| * On KASLR use 1 GiB by default, leaving 1 GiB for modules once the |
| * page tables are fully set up. |
| * |
| * If KASLR is disabled we can shrink it to 0.5 GiB and increase the size |
| * of the modules area to 1.5 GiB. |
| */ |
| #ifdef CONFIG_RANDOMIZE_BASE |
| #define KERNEL_IMAGE_SIZE (1024 * 1024 * 1024) |
| #else |
| #define KERNEL_IMAGE_SIZE (512 * 1024 * 1024) |
| #endif |
| |
| #endif /* _ASM_X86_PAGE_64_DEFS_H */ |