Re: [PATCH] h8300: switch to NO_BOOTMEM

[Yoshinori Sato]

On Sat, 17 Mar 2018 06:33:06 +0900,
Rob Herring wrote:
> 
> Commit 0fa1c579349f ("of/fdt: use memblock_virt_alloc for early alloc")
> inadvertently switched the DT unflattening allocations from memblock to
> bootmem which doesn't work because the unflattening happens before
> bootmem is initialized. Swapping the order of bootmem init and
> unflattening could also fix this, but removing bootmem is desired. So
> enable NO_BOOTMEM on h8300 like other architectures have done.
> 
> Fixes: 0fa1c579349f ("of/fdt: use memblock_virt_alloc for early alloc")
> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
> Cc: uclinux-h8-devel@xxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> I haven't seen any reports, but 4.16 is likely broken. This is compile 
> tested only.
> 
> Moving unflattening after bootmem_init should also work if a smaller 
> change for 4.16 is desired.

It's works fine.
Applied to h8300-next.

Thanks.

> Rob
> 
>  arch/h8300/Kconfig        |  1 +
>  arch/h8300/kernel/setup.c | 36 ++++++++----------------------------
>  2 files changed, 9 insertions(+), 28 deletions(-)
> 
> diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig
> index 091d6d04b5e5..efc602634064 100644
> --- a/arch/h8300/Kconfig
> +++ b/arch/h8300/Kconfig
> @@ -16,6 +16,7 @@ config H8300
>  	select OF_IRQ
>  	select OF_EARLY_FLATTREE
>  	select HAVE_MEMBLOCK
> +	select NO_BOOTMEM
>  	select TIMER_OF
>  	select H8300_TMR8
>  	select HAVE_KERNEL_GZIP
> diff --git a/arch/h8300/kernel/setup.c b/arch/h8300/kernel/setup.c
> index a4d0470c10a9..33ed980e7aea 100644
> --- a/arch/h8300/kernel/setup.c
> +++ b/arch/h8300/kernel/setup.c
> @@ -71,10 +71,6 @@ void __init h8300_fdt_init(void *fdt, char *bootargs)
>  
>  static void __init bootmem_init(void)
>  {
> -	int bootmap_size;
> -	unsigned long ram_start_pfn;
> -	unsigned long free_ram_start_pfn;
> -	unsigned long ram_end_pfn;
>  	struct memblock_region *region;
>  
>  	memory_end = memory_start = 0;
> @@ -88,33 +84,17 @@ static void __init bootmem_init(void)
>  	if (!memory_end)
>  		panic("No memory!");
>  
> -	ram_start_pfn = PFN_UP(memory_start);
> -	/* free_ram_start_pfn is first page after kernel */
> -	free_ram_start_pfn = PFN_UP(__pa(_end));
> -	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
> +	/* setup bootmem globals (we use no_bootmem, but mm still depends on this) */
> +	min_low_pfn = PFN_UP(memory_start);
> +	max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
> +	max_pfn = max_low_pfn;
>  
> -	max_pfn = ram_end_pfn;
> +	memblock_reserve(__pa(_stext), _end - _stext);
>  
> -	/*
> -	 * give all the memory to the bootmap allocator,  tell it to put the
> -	 * boot mem_map at the start of memory
> -	 */
> -	bootmap_size = init_bootmem_node(NODE_DATA(0),
> -					 free_ram_start_pfn,
> -					 0,
> -					 ram_end_pfn);
> -	/*
> -	 * free the usable memory,  we have to make sure we do not free
> -	 * the bootmem bitmap so we then reserve it after freeing it :-)
> -	 */
> -	free_bootmem(PFN_PHYS(free_ram_start_pfn),
> -		     (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
> -	reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
> -			BOOTMEM_DEFAULT);
> +	early_init_fdt_reserve_self();
> +	early_init_fdt_scan_reserved_mem();
>  
> -	for_each_memblock(reserved, region) {
> -		reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
> -	}
> +	memblock_dump_all();
>  }
>  
>  void __init setup_arch(char **cmdline_p)
> -- 
> 2.14.1
> 

-- 
Yoshinori Sato
<ysato@xxxxxxxxxxxxxxxxxxxx>