diff --git a/Documentation/riscv/vm-layout.rst b/Documentation/riscv/vm-layout.rst index b7f98930d38d39..1bd687b971046b 100644 --- a/Documentation/riscv/vm-layout.rst +++ b/Documentation/riscv/vm-layout.rst @@ -47,12 +47,12 @@ RISC-V Linux Kernel SV39 | Kernel-space virtual memory, shared between all processes: ____________________________________________________________|___________________________________________________________ | | | | - ffffffc000000000 | -256 GB | ffffffc7ffffffff | 32 GB | kasan - ffffffcefee00000 | -196 GB | ffffffcefeffffff | 2 MB | fixmap - ffffffceff000000 | -196 GB | ffffffceffffffff | 16 MB | PCI io - ffffffcf00000000 | -196 GB | ffffffcfffffffff | 4 GB | vmemmap - ffffffd000000000 | -192 GB | ffffffdfffffffff | 64 GB | vmalloc/ioremap space - ffffffe000000000 | -128 GB | ffffffff7fffffff | 124 GB | direct mapping of all physical memory + ffffffc6fee00000 | -228 GB | ffffffc6feffffff | 2 MB | fixmap + ffffffc6ff000000 | -228 GB | ffffffc6ffffffff | 16 MB | PCI io + ffffffc700000000 | -228 GB | ffffffc7ffffffff | 4 GB | vmemmap + ffffffc800000000 | -224 GB | ffffffd7ffffffff | 64 GB | vmalloc/ioremap space + ffffffd800000000 | -160 GB | fffffff6ffffffff | 124 GB | direct mapping of all physical memory + fffffff700000000 | -36 GB | fffffffeffffffff | 32 GB | kasan __________________|____________|__________________|_________|____________________________________________________________ | | diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 7a68a4106e5a06..7f8aea33329165 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -160,12 +160,12 @@ config PAGE_OFFSET hex default 0xC0000000 if 32BIT default 0x80000000 if 64BIT && !MMU - default 0xffffffe000000000 if 64BIT + default 0xffffffd800000000 if 64BIT config KASAN_SHADOW_OFFSET hex depends on KASAN_GENERIC - default 0xdfffffc800000000 if 64BIT + default 0xdfffffff00000000 if 64BIT default 0xffffffff if 32BIT config ARCH_FLATMEM_ENABLE diff --git a/arch/riscv/include/asm/kasan.h b/arch/riscv/include/asm/kasan.h index b00f503ec1248a..257a2495145ab9 100644 --- a/arch/riscv/include/asm/kasan.h +++ b/arch/riscv/include/asm/kasan.h @@ -28,8 +28,8 @@ #define KASAN_SHADOW_SCALE_SHIFT 3 #define KASAN_SHADOW_SIZE (UL(1) << ((CONFIG_VA_BITS - 1) - KASAN_SHADOW_SCALE_SHIFT)) -#define KASAN_SHADOW_START KERN_VIRT_START -#define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE) +#define KASAN_SHADOW_START (KASAN_SHADOW_END - KASAN_SHADOW_SIZE) +#define KASAN_SHADOW_END MODULES_LOWEST_VADDR #define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL) void kasan_init(void); diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h index b3e5ff0125fe48..a18c989e600c83 100644 --- a/arch/riscv/include/asm/page.h +++ b/arch/riscv/include/asm/page.h @@ -33,8 +33,6 @@ */ #define PAGE_OFFSET _AC(CONFIG_PAGE_OFFSET, UL) -#define KERN_VIRT_SIZE (-PAGE_OFFSET) - #ifndef __ASSEMBLY__ #define clear_page(pgaddr) memset((pgaddr), 0, PAGE_SIZE) diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index bf204e7c1f7425..fa400b2abb3665 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -24,6 +24,17 @@ #define KERNEL_LINK_ADDR PAGE_OFFSET #endif +/* Number of entries in the page global directory */ +#define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t)) +/* Number of entries in the page table */ +#define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t)) + +/* + * Half of the kernel address space (half of the entries of the page global + * directory) is for the direct mapping. + */ +#define KERN_VIRT_SIZE ((PTRS_PER_PGD / 2 * PGDIR_SIZE) / 2) + #define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1) #define VMALLOC_END (PAGE_OFFSET - 1) #define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE) @@ -39,8 +50,10 @@ /* Modules always live before the kernel */ #ifdef CONFIG_64BIT -#define MODULES_VADDR (PFN_ALIGN((unsigned long)&_end) - SZ_2G) -#define MODULES_END (PFN_ALIGN((unsigned long)&_start)) +/* This is used to define the end of the KASAN shadow region */ +#define MODULES_LOWEST_VADDR (KERNEL_LINK_ADDR - SZ_2G) +#define MODULES_VADDR (PFN_ALIGN((unsigned long)&_end) - SZ_2G) +#define MODULES_END (PFN_ALIGN((unsigned long)&_start)) #endif /* @@ -108,11 +121,6 @@ #endif /* CONFIG_XIP_KERNEL */ #ifdef CONFIG_MMU -/* Number of entries in the page global directory */ -#define PTRS_PER_PGD (PAGE_SIZE / sizeof(pgd_t)) -/* Number of entries in the page table */ -#define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t)) - /* Number of PGD entries that a user-mode program can use */ #define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 24b2b80446020f..f515964e9c0071 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -103,6 +103,9 @@ static void __init print_vm_layout(void) print_mlm("lowmem", (unsigned long)PAGE_OFFSET, (unsigned long)high_memory); #ifdef CONFIG_64BIT +#ifdef CONFIG_KASAN + print_mlm("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END); +#endif print_mlm("kernel", (unsigned long)KERNEL_LINK_ADDR, (unsigned long)ADDRESS_SPACE_END); #endif @@ -130,18 +133,8 @@ void __init mem_init(void) print_vm_layout(); } -/* - * The default maximal physical memory size is -PAGE_OFFSET for 32-bit kernel, - * whereas for 64-bit kernel, the end of the virtual address space is occupied - * by the modules/BPF/kernel mappings which reduces the available size of the - * linear mapping. - * Limit the memory size via mem. - */ -#ifdef CONFIG_64BIT -static phys_addr_t memory_limit = -PAGE_OFFSET - SZ_4G; -#else -static phys_addr_t memory_limit = -PAGE_OFFSET; -#endif +/* Limit the memory size via mem. */ +static phys_addr_t memory_limit; static int __init early_mem(char *p) { @@ -612,6 +605,14 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) riscv_pfn_base = PFN_DOWN(kernel_map.phys_addr); + /* + * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit + * kernel, whereas for 64-bit kernel, the end of the virtual address + * space is occupied by the modules/BPF/kernel mappings which reduces + * the available size of the linear mapping. + */ + memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0); + /* Sanity check alignment and size */ BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0);