diff mbox series

[v3,2/4] RISC-V: Fix memory reservation in setup_bootmem()

Message ID 20190325092234.5451-3-anup.patel@wdc.com (mailing list archive)
State New, archived
Headers show
Series Boot RISC-V kernel from any 4KB aligned address | expand

Commit Message

Anup Patel March 25, 2019, 9:23 a.m. UTC 
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.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 arch/riscv/mm/init.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

Comments

Christoph Hellwig March 25, 2019, 11:38 a.m. UTC | #1 
On Mon, Mar 25, 2019 at 09:23:09AM +0000, Anup Patel wrote:
> 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.
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>

Shouldn't this be a Suggested-by?
Mike Rapoport March 25, 2019, 4:13 p.m. UTC | #2 
On Mon, Mar 25, 2019 at 09:23:09AM +0000, Anup Patel wrote:
> 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.
> 
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>

Suggested-by: please :)

> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>

Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>

> ---
>  arch/riscv/mm/init.c | 17 ++++++++---------
>  1 file changed, 8 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 8cf9ff1f9058..3e66b7cb3a61 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -29,6 +29,8 @@ 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, };
> @@ -108,23 +110,21 @@ 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);
> +		if (reg->base <= vmlinux_end && vmlinux_end <= end)
>  			mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
> -		}
>  	}
>  	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());
>  
> @@ -196,7 +196,6 @@ 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);
> -- 
> 2.17.1
>
Palmer Dabbelt April 24, 2019, 9:06 p.m. UTC | #3 
On Mon, 25 Mar 2019 02:23:09 PDT (-0700), Anup.Patel@wdc.com wrote:
> 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.
>
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
> Signed-off-by: Anup Patel <anup.patel@wdc.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> ---
>  arch/riscv/mm/init.c | 17 ++++++++---------
>  1 file changed, 8 insertions(+), 9 deletions(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 8cf9ff1f9058..3e66b7cb3a61 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -29,6 +29,8 @@ 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, };
> @@ -108,23 +110,21 @@ 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);
> +		if (reg->base <= vmlinux_end && vmlinux_end <= end)
>  			mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
> -		}
>  	}
>  	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());
>  
> @@ -196,7 +196,6 @@ 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);
> -- 
> 2.17.1

I've already merged your first patch for 5.1, but I'm going through and
collecting 5.2 patches now and it appears this has a conflict.  Do you mind
re-submitting the patch set against rc6?
diff mbox series

Patch

diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 8cf9ff1f9058..3e66b7cb3a61 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -29,6 +29,8 @@  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, };
@@ -108,23 +110,21 @@  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);
+		if (reg->base <= vmlinux_end && vmlinux_end <= end)
 			mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
-		}
 	}
 	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());
 
@@ -196,7 +196,6 @@  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);