diff --git a/Documentation/riscv/vm-layout.rst b/Documentation/riscv/vm-layout.rst
index b7f98930d38d396501f11851434beef189da59ee..1bd687b971046b34df459cf085860598a29777fd 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 7a68a4106e5a06e32fe834d6bcbb6e13386bb7c1..7f8aea33329165a2937b55980f072325de2838c7 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 b00f503ec1248a5eea682027ca4a5d673d105fae..257a2495145ab96271ceafbf532793a31ca13056 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 b3e5ff0125fe48ce7398c60e14a241492aa9660d..a18c989e600c8333ccea364f57cb0ecf2e8d664f 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 bf204e7c1f7425b7a43cd004fd4fb1ff5bcd71e6..fa400b2abb366593f39e5ea3ee233633870016b9 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 24b2b80446020fe684454c4c6c09b8489da39d60..f515964e9c0071f1fcad219f1cd85fe7012f6523 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);