diff options
Diffstat (limited to 'arch/riscv/mm/init.c')
| -rw-r--r-- | arch/riscv/mm/init.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index e3218d65f21d..e3405e4b99af 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -250,18 +250,19 @@ static void __init setup_bootmem(void) kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base; /* - * memblock allocator is not aware of the fact that last 4K bytes of - * the addressable memory can not be mapped because of IS_ERR_VALUE - * macro. Make sure that last 4k bytes are not usable by memblock - * if end of dram is equal to maximum addressable memory. For 64-bit - * kernel, this problem can't happen here as the end of the virtual - * address space is occupied by the kernel mapping then this check must - * be done as soon as the kernel mapping base address is determined. + * Reserve physical address space that would be mapped to virtual + * addresses greater than (void *)(-PAGE_SIZE) because: + * - This memory would overlap with ERR_PTR + * - This memory belongs to high memory, which is not supported + * + * This is not applicable to 64-bit kernel, because virtual addresses + * after (void *)(-PAGE_SIZE) are not linearly mapped: they are + * occupied by kernel mapping. Also it is unrealistic for high memory + * to exist on 64-bit platforms. */ if (!IS_ENABLED(CONFIG_64BIT)) { - max_mapped_addr = __pa(~(ulong)0); - if (max_mapped_addr == (phys_ram_end - 1)) - memblock_set_current_limit(max_mapped_addr - 4096); + max_mapped_addr = __va_to_pa_nodebug(-PAGE_SIZE); + memblock_reserve(max_mapped_addr, (phys_addr_t)-max_mapped_addr); } min_low_pfn = PFN_UP(phys_ram_base); |