Re: [PATCH] h8300: switch to NO_BOOTMEM

From: Yoshinori Sato
Date: Wed May 09 2018 - 01:20:47 EST


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>