Re: [PATCH 02/13] csky: move setup_initrd() to setup.c

[Guo Ren <guoren@kernel.org>]

Move setup_initrd from mem_init into memblock_init, that LGTM.

Acked by: Guo Ren (csky) <guoren@kernel.org>

On Fri, Mar 7, 2025 at 2:52 AM Mike Rapoport <rppt@kernel.org> wrote:
>
> From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
>
> Memory used by initrd should be reserved as soon as possible before
> there any memblock allocations that might overwrite that memory.
>
> This will also help with pulling out memblock_free_all() to the generic
> code and reducing code duplication in arch::mem_init().
>
> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
> ---
>  arch/csky/kernel/setup.c | 43 ++++++++++++++++++++++++++++++++++++++++
>  arch/csky/mm/init.c      | 43 ----------------------------------------
>  2 files changed, 43 insertions(+), 43 deletions(-)
>
> diff --git a/arch/csky/kernel/setup.c b/arch/csky/kernel/setup.c
> index fe715b707fd0..e0d6ca86ea8c 100644
> --- a/arch/csky/kernel/setup.c
> +++ b/arch/csky/kernel/setup.c
> @@ -12,6 +12,45 @@
>  #include <asm/mmu_context.h>
>  #include <asm/pgalloc.h>
>
> +#ifdef CONFIG_BLK_DEV_INITRD
> +static void __init setup_initrd(void)
> +{
> +       unsigned long size;
> +
> +       if (initrd_start >= initrd_end) {
> +               pr_err("initrd not found or empty");
> +               goto disable;
> +       }
> +
> +       if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
> +               pr_err("initrd extends beyond end of memory");
> +               goto disable;
> +       }
> +
> +       size = initrd_end - initrd_start;
> +
> +       if (memblock_is_region_reserved(__pa(initrd_start), size)) {
> +               pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region",
> +                      __pa(initrd_start), size);
> +               goto disable;
> +       }
> +
> +       memblock_reserve(__pa(initrd_start), size);
> +
> +       pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
> +               (void *)(initrd_start), size);
> +
> +       initrd_below_start_ok = 1;
> +
> +       return;
> +
> +disable:
> +       initrd_start = initrd_end = 0;
> +
> +       pr_err(" - disabling initrd\n");
> +}
> +#endif
> +
>  static void __init csky_memblock_init(void)
>  {
>         unsigned long lowmem_size = PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
> @@ -40,6 +79,10 @@ static void __init csky_memblock_init(void)
>                 max_low_pfn = min_low_pfn + sseg_size;
>         }
>
> +#ifdef CONFIG_BLK_DEV_INITRD
> +       setup_initrd();
> +#endif
> +
>         max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
>
>         mmu_init(min_low_pfn, max_low_pfn);
> diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c
> index bde7cabd23df..ab51acbc19b2 100644
> --- a/arch/csky/mm/init.c
> +++ b/arch/csky/mm/init.c
> @@ -42,45 +42,6 @@ unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
>                                                 __page_aligned_bss;
>  EXPORT_SYMBOL(empty_zero_page);
>
> -#ifdef CONFIG_BLK_DEV_INITRD
> -static void __init setup_initrd(void)
> -{
> -       unsigned long size;
> -
> -       if (initrd_start >= initrd_end) {
> -               pr_err("initrd not found or empty");
> -               goto disable;
> -       }
> -
> -       if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
> -               pr_err("initrd extends beyond end of memory");
> -               goto disable;
> -       }
> -
> -       size = initrd_end - initrd_start;
> -
> -       if (memblock_is_region_reserved(__pa(initrd_start), size)) {
> -               pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region",
> -                      __pa(initrd_start), size);
> -               goto disable;
> -       }
> -
> -       memblock_reserve(__pa(initrd_start), size);
> -
> -       pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
> -               (void *)(initrd_start), size);
> -
> -       initrd_below_start_ok = 1;
> -
> -       return;
> -
> -disable:
> -       initrd_start = initrd_end = 0;
> -
> -       pr_err(" - disabling initrd\n");
> -}
> -#endif
> -
>  void __init mem_init(void)
>  {
>  #ifdef CONFIG_HIGHMEM
> @@ -92,10 +53,6 @@ void __init mem_init(void)
>  #endif
>         high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
>
> -#ifdef CONFIG_BLK_DEV_INITRD
> -       setup_initrd();
> -#endif
> -
>         memblock_free_all();
>
>  #ifdef CONFIG_HIGHMEM
> --
> 2.47.2
>


-- 
Best Regards
 Guo Ren