From d90d45d7dcb732f0d4fbb3b99164ae54999612d5 Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Fri, 7 Jun 2019 06:01:29 +0000 Subject: RISC-V: Fix memory reservation in setup_bootmem() Currently, the setup_bootmem() reserves memory from RAM start to the kernel end. This prevents us from exploring ways to use the RAM below (or before) the kernel start hence this patch updates setup_bootmem() to only reserve memory from the kernel start to the kernel end. Suggested-by: Mike Rapoport Signed-off-by: Anup Patel Reviewed-by: Christoph Hellwig Signed-off-by: Paul Walmsley --- arch/riscv/mm/init.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'arch/riscv') diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 84747d7a1e85..160d79d58dd5 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -21,6 +21,8 @@ unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss; EXPORT_SYMBOL(empty_zero_page); +extern char _start[]; + static void __init zone_sizes_init(void) { unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, }; @@ -95,18 +97,14 @@ void __init setup_bootmem(void) { struct memblock_region *reg; phys_addr_t mem_size = 0; + phys_addr_t vmlinux_end = __pa(&_end); + phys_addr_t vmlinux_start = __pa(&_start); /* Find the memory region containing the kernel */ for_each_memblock(memory, reg) { - phys_addr_t vmlinux_end = __pa(_end); phys_addr_t end = reg->base + reg->size; if (reg->base <= vmlinux_end && vmlinux_end <= end) { - /* - * Reserve from the start of the region to the end of - * the kernel - */ - memblock_reserve(reg->base, vmlinux_end - reg->base); mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET); /* @@ -120,6 +118,9 @@ void __init setup_bootmem(void) } BUG_ON(mem_size == 0); + /* Reserve from the start of the kernel to the end of the kernel */ + memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); + set_max_mapnr(PFN_DOWN(mem_size)); max_low_pfn = PFN_DOWN(memblock_end_of_DRAM()); @@ -197,7 +198,6 @@ void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot) asmlinkage void __init setup_vm(void) { - extern char _start; uintptr_t i; uintptr_t pa = (uintptr_t) &_start; pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC); -- cgit v1.2.3-55-g7522