[PATCH 08/40] efi: Correct address handling with ACPI tables

[Heinrich Schuchardt]

On 12/1/21 17:02, Simon Glass wrote:
> The current EFI implementation confuses pointers and addresses. Normally
> we can get away with this but in the case of sandbox it causes failures.
>
> Despite the fact that efi_allocate_pages() returns a u64, it is actually
> a pointer, not an address. Add special handling to avoid a crash when
> running 'bootefi hello'.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
>   lib/efi_loader/efi_acpi.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/lib/efi_loader/efi_acpi.c b/lib/efi_loader/efi_acpi.c
> index 016bbf6db33..9d101aa843e 100644
> --- a/lib/efi_loader/efi_acpi.c
> +++ b/lib/efi_loader/efi_acpi.c
> @@ -8,6 +8,7 @@
>   #include <common.h>
>   #include <efi_loader.h>
>   #include <log.h>
> +#include <mapmem.h>
>   #include <acpi/acpi_table.h>
>
>   static const efi_guid_t acpi_guid = EFI_ACPI_TABLE_GUID;
> @@ -22,6 +23,7 @@ efi_status_t efi_acpi_register(void)
>   	/* Map within the low 32 bits, to allow for 32bit ACPI tables */
>   	u64 acpi = U32_MAX;
>   	efi_status_t ret;
> +	ulong addr;
>
>   	/* Reserve 64kiB page for ACPI */
>   	ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
> @@ -34,7 +36,8 @@ efi_status_t efi_acpi_register(void)
>   	 * a 4k-aligned address, so it is safe to assume that
>   	 * write_acpi_tables() will write the table at that address.
>   	 */
> -	write_acpi_tables((ulong)acpi);
> +	addr = map_to_sysmem((void *)(ulong)acpi);

Please, don't pollute general code with sandbox specific stuff where
this can be avoided.

write_acpi_tables() anyway converts to a pointer. We should not convert
twice. Correct the parameter of write_acpi_tables() instead to expect a
pointer.

Best regards

Heinrich

> +	write_acpi_tables(addr);
>
>   	/* And expose them to our EFI payload */
>   	return efi_install_configuration_table(&acpi_guid,
>