[PATCH 6/8] arm64/efi: ignore DT memory nodes instead of removing them

Ganapatrao Kulkarni gpkulkarni at gmail.com
Mon May 11 09:28:27 PDT 2015


On Mon, May 11, 2015 at 12:11 PM, Ard Biesheuvel
<ard.biesheuvel at linaro.org> wrote:
> There are two problems with the UEFI stub DT memory node removal
> routine:
> - it deletes nodes as it traverses the tree, which happens to work
>   but is not supported, as deletion invalidates the node iterator;
> - deleting memory nodes entirely may discard annotations in the form
>   of additional properties on the nodes.
>
> Now that the UEFI initialization has moved to an earlier stage, we can
> actually just ignore any memblocks that are installed after we have
> processed the UEFI memory map. This way, it is no longer necessary to
> remove the nodes, so we can remove that logic from the stub as well.
>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
> ---
>  arch/arm64/mm/init.c               |  7 +++++++
>  drivers/firmware/efi/libstub/fdt.c | 24 +-----------------------
>  2 files changed, 8 insertions(+), 23 deletions(-)
>
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 64480b65ef17..95c239f43384 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -386,6 +386,13 @@ __setup("keepinitrd", keepinitrd_setup);
>
>  void __init early_init_dt_add_memory_arch(u64 base, u64 size)
>  {
> +       /*
> +        * EFI_MEMMAP will be set /after/ UEFI has installed all memory based
> +        * on the content of the UEFI memory map.
> +        */
> +       if (efi_enabled(EFI_MEMMAP))
> +               return;
> +
>         if (!PAGE_ALIGNED(base)) {
>                 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
>                         pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
> diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
> index ef5d764e2a27..343e7992bd8f 100644
> --- a/drivers/firmware/efi/libstub/fdt.c
> +++ b/drivers/firmware/efi/libstub/fdt.c
> @@ -24,7 +24,7 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
>                         unsigned long map_size, unsigned long desc_size,
>                         u32 desc_ver)
>  {
> -       int node, prev, num_rsv;
> +       int node, num_rsv;
>         int status;
>         u32 fdt_val32;
>         u64 fdt_val64;
> @@ -54,28 +54,6 @@ efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
>                 goto fdt_set_fail;
>
>         /*
> -        * Delete any memory nodes present. We must delete nodes which
> -        * early_init_dt_scan_memory may try to use.
> -        */
> -       prev = 0;
> -       for (;;) {
> -               const char *type;
> -               int len;
> -
> -               node = fdt_next_node(fdt, prev, NULL);
> -               if (node < 0)
> -                       break;
> -
> -               type = fdt_getprop(fdt, node, "device_type", &len);
> -               if (type && strncmp(type, "memory", len) == 0) {
> -                       fdt_del_node(fdt, node);
> -                       continue;
> -               }
> -
> -               prev = node;
> -       }
> -
> -       /*
>          * Delete all memory reserve map entries. When booting via UEFI,
>          * kernel will use the UEFI memory map to find reserved regions.
>          */
> --
> 1.9.1
>
>
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Thanks Ard.
Tested this patch on my numa setup.

Tested-by: Ganapatrao Kulkarni <gkulkarni at caviumnetworks.com>

thanks
Ganapat



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