diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index bfa2dea95354ff..8b698d9609e701 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -234,8 +234,6 @@ static void __init setup_bootmem(void) */ memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); - phys_ram_end = memblock_end_of_DRAM(); - /* * Make sure we align the start of the memory on a PMD boundary so that * at worst, we map the linear mapping with PMD mappings. @@ -250,6 +248,16 @@ static void __init setup_bootmem(void) if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU)) kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base; + /* + * The size of the linear page mapping may restrict the amount of + * usable RAM. + */ + if (IS_ENABLED(CONFIG_64BIT)) { + max_mapped_addr = __pa(PAGE_OFFSET) + KERN_VIRT_SIZE; + memblock_cap_memory_range(phys_ram_base, + max_mapped_addr - phys_ram_base); + } + /* * Reserve physical address space that would be mapped to virtual * addresses greater than (void *)(-PAGE_SIZE) because: @@ -266,6 +274,7 @@ static void __init setup_bootmem(void) memblock_reserve(max_mapped_addr, (phys_addr_t)-max_mapped_addr); } + phys_ram_end = memblock_end_of_DRAM(); min_low_pfn = PFN_UP(phys_ram_base); max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end); high_memory = (void *)(__va(PFN_PHYS(max_low_pfn))); @@ -1284,8 +1293,6 @@ static void __init create_linear_mapping_page_table(void) if (start <= __pa(PAGE_OFFSET) && __pa(PAGE_OFFSET) < end) start = __pa(PAGE_OFFSET); - if (end >= __pa(PAGE_OFFSET) + memory_limit) - end = __pa(PAGE_OFFSET) + memory_limit; create_linear_mapping_range(start, end, 0, NULL); }