Re: [PATCH v2 2/2] efi/fdt: Simplify get_fdt flow

From: Ard Biesheuvel
Date: Mon Nov 05 2018 - 07:41:31 EST


On 29 October 2018 at 11:15, Julien Thierry <julien.thierry@xxxxxxx> wrote:
> Reorganize get_fdt lookup loop, clearly showing that:
> - Nothing is done for table entries that do not have fdt_guid
> - Once an entry with fdt_guid is found, break out of the loop
>
> No functional changes.
>
> Signed-off-by: Julien Thierry <julien.thierry@xxxxxxx>
> Suggested-by: Joe Perches <joe@xxxxxxxxxxx>
> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
> ---
> drivers/firmware/efi/libstub/fdt.c | 25 +++++++++++++------------
> 1 file changed, 13 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
> index 8b6696e..5b7e2b3 100644
> --- a/drivers/firmware/efi/libstub/fdt.c
> +++ b/drivers/firmware/efi/libstub/fdt.c
> @@ -366,23 +366,24 @@ void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
> {
> efi_guid_t fdt_guid = DEVICE_TREE_GUID;
> efi_config_table_t *tables;
> - void *fdt;
> int i;
>
> - tables = (efi_config_table_t *) sys_table->tables;
> - fdt = NULL;
> + tables = (efi_config_table_t *)sys_table->tables;
>
> for (i = 0; i < sys_table->nr_tables; i++) {
> - if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
> - fdt = (void *) tables[i].table;
> - if (fdt_check_header(fdt) != 0) {
> - pr_efi_err(sys_table, "Invalid header detected on UEFI supplied FDT, ignoring ...\n");
> - return NULL;
> - }
> - *fdt_size = fdt_totalsize(fdt);
> - break;
> + void *fdt;
> +
> + if (efi_guidcmp(tables[i].guid, fdt_guid) != 0)
> + continue;
> +
> + fdt = (void *) tables[i].table;
> + if (fdt_check_header(fdt) != 0) {
> + pr_efi_err(sys_table, "Invalid header detected on UEFI supplied FDT, ignoring ...\n");
> + return NULL;
> }
> + *fdt_size = fdt_totalsize(fdt);
> + return fdt;
> }
>
> - return fdt;
> + return NULL;
> }
> --
> 1.9.1
>

Queued in efi/next

Thanks.