Re: [PATCH 2/2] x86/xen/efi: Init only efi struct members used by Xen

From: Ard Biesheuvel
Date: Wed Jun 21 2017 - 03:54:10 EST


On 20 June 2017 at 22:14, Daniel Kiper <daniel.kiper@xxxxxxxxxx> wrote:
> Current approach, wholesale efi struct initialization from efi_xen, is not
> good. Usually if new member is defined then it is properly initialized in
> drivers/firmware/efi/efi.c but not in arch/x86/xen/efi.c. As I saw it happened
> a few times until now. So, let's initialize only efi struct members used by
> Xen to avoid such issues in the future.
>
> Signed-off-by: Daniel Kiper <daniel.kiper@xxxxxxxxxx>

Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

> ---
> arch/x86/xen/efi.c | 45 ++++++++++++---------------------------------
> 1 file changed, 12 insertions(+), 33 deletions(-)
>
> diff --git a/arch/x86/xen/efi.c b/arch/x86/xen/efi.c
> index 30bb2e8..01b9faf 100644
> --- a/arch/x86/xen/efi.c
> +++ b/arch/x86/xen/efi.c
> @@ -54,38 +54,6 @@
> .tables = EFI_INVALID_TABLE_ADDR /* Initialized later. */
> };
>
> -static const struct efi efi_xen __initconst = {
> - .systab = NULL, /* Initialized later. */
> - .runtime_version = 0, /* Initialized later. */
> - .mps = EFI_INVALID_TABLE_ADDR,
> - .acpi = EFI_INVALID_TABLE_ADDR,
> - .acpi20 = EFI_INVALID_TABLE_ADDR,
> - .smbios = EFI_INVALID_TABLE_ADDR,
> - .smbios3 = EFI_INVALID_TABLE_ADDR,
> - .sal_systab = EFI_INVALID_TABLE_ADDR,
> - .boot_info = EFI_INVALID_TABLE_ADDR,
> - .hcdp = EFI_INVALID_TABLE_ADDR,
> - .uga = EFI_INVALID_TABLE_ADDR,
> - .uv_systab = EFI_INVALID_TABLE_ADDR,
> - .fw_vendor = EFI_INVALID_TABLE_ADDR,
> - .runtime = EFI_INVALID_TABLE_ADDR,
> - .config_table = EFI_INVALID_TABLE_ADDR,
> - .get_time = xen_efi_get_time,
> - .set_time = xen_efi_set_time,
> - .get_wakeup_time = xen_efi_get_wakeup_time,
> - .set_wakeup_time = xen_efi_set_wakeup_time,
> - .get_variable = xen_efi_get_variable,
> - .get_next_variable = xen_efi_get_next_variable,
> - .set_variable = xen_efi_set_variable,
> - .query_variable_info = xen_efi_query_variable_info,
> - .update_capsule = xen_efi_update_capsule,
> - .query_capsule_caps = xen_efi_query_capsule_caps,
> - .get_next_high_mono_count = xen_efi_get_next_high_mono_count,
> - .reset_system = xen_efi_reset_system,
> - .set_virtual_address_map = NULL, /* Not used under Xen. */
> - .flags = 0 /* Initialized later. */
> -};
> -
> static efi_system_table_t __init *xen_efi_probe(void)
> {
> struct xen_platform_op op = {
> @@ -102,7 +70,18 @@ static efi_system_table_t __init *xen_efi_probe(void)
>
> /* Here we know that Xen runs on EFI platform. */
>
> - efi = efi_xen;
> + efi.get_time = xen_efi_get_time;
> + efi.set_time = xen_efi_set_time;
> + efi.get_wakeup_time = xen_efi_get_wakeup_time;
> + efi.set_wakeup_time = xen_efi_set_wakeup_time;
> + efi.get_variable = xen_efi_get_variable;
> + efi.get_next_variable = xen_efi_get_next_variable;
> + efi.set_variable = xen_efi_set_variable;
> + efi.query_variable_info = xen_efi_query_variable_info;
> + efi.update_capsule = xen_efi_update_capsule;
> + efi.query_capsule_caps = xen_efi_query_capsule_caps;
> + efi.get_next_high_mono_count = xen_efi_get_next_high_mono_count;
> + efi.reset_system = xen_efi_reset_system;
>
> efi_systab_xen.tables = info->cfg.addr;
> efi_systab_xen.nr_tables = info->cfg.nent;
> --
> 1.7.10.4
>