[PATCH v2 1/1] efi_loader: put device tree into EfiACPIReclaimMemory

[Grant Likely]

On 07/05/2020 19:19, Heinrich Schuchardt wrote:
> According to the UEFI spec ACPI tables should be placed in
> EfiACPIReclaimMemory. Let's do the same with the device tree.
> 
> Suggested-by: Ard Biesheuvel <ardb at kernel.org>
> Cc: Grant Likely <grant.likely at arm.com>
> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
> ---
> v2:
> 	adjust the unit test

Is there any impact to changing the memory type for current users? Does 
the kernel currently expect the EFI_BOOT_SERVICES_DATA memory type? What 
happens if Grub or another EFI application replaces the DTB table? Will 
it try to use a different memory type, and will that matter?

g.

> ---
>   cmd/bootefi.c                          | 4 ++--
>   lib/efi_selftest/efi_selftest_memory.c | 4 ++--
>   2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
> index 54b4b8f984..06573b14e9 100644
> --- a/cmd/bootefi.c
> +++ b/cmd/bootefi.c
> @@ -127,13 +127,13 @@ static efi_status_t copy_fdt(void **fdtp)
>   	new_fdt_addr = (uintptr_t)map_sysmem(fdt_ram_start + 0x7f00000 +
>   					     fdt_size, 0);
>   	ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
> -				 EFI_BOOT_SERVICES_DATA, fdt_pages,
> +				 EFI_ACPI_RECLAIM_MEMORY, fdt_pages,
>   				 &new_fdt_addr);
>   	if (ret != EFI_SUCCESS) {
>   		/* If we can't put it there, put it somewhere */
>   		new_fdt_addr = (ulong)memalign(EFI_PAGE_SIZE, fdt_size);
>   		ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
> -					 EFI_BOOT_SERVICES_DATA, fdt_pages,
> +					 EFI_ACPI_RECLAIM_MEMORY, fdt_pages,
>   					 &new_fdt_addr);
>   		if (ret != EFI_SUCCESS) {
>   			printf("ERROR: Failed to reserve space for FDT\n");
> diff --git a/lib/efi_selftest/efi_selftest_memory.c b/lib/efi_selftest/efi_selftest_memory.c
> index e71732dc6d..4d32a28006 100644
> --- a/lib/efi_selftest/efi_selftest_memory.c
> +++ b/lib/efi_selftest/efi_selftest_memory.c
> @@ -176,9 +176,9 @@ static int execute(void)
>   	/* Check memory reservation for the device tree */
>   	if (fdt_addr &&
>   	    find_in_memory_map(map_size, memory_map, desc_size, fdt_addr,
> -			       EFI_BOOT_SERVICES_DATA) != EFI_ST_SUCCESS) {
> +			       EFI_ACPI_RECLAIM_MEMORY) != EFI_ST_SUCCESS) {
>   		efi_st_error
> -			("Device tree not marked as boot services data\n");
> +			("Device tree not marked as ACPI reclaim memory\n");
>   		return EFI_ST_FAILURE;
>   	}
>   	return EFI_ST_SUCCESS;
> --
> 2.26.2
>