I thought I had sent out my comment when this patch was submitted first time,
but it seems that it has never reached out to ML.
On Sun, Apr 10, 2022 at 04:05:55PM -0500, kev...@freebsd.org wrote:
> From: Kyle Evans <kev...@freebsd.org>
>
> Up until commit 5f59518a7b1ae ("efi_loader: setting boot device"), we
> could boot an arbitrary blob with bootefi. Indeed, efi_run_image() even
> has a special case for missing device paths indicating a payload that
> was directly loaded via JTAG, for example.
>
> Restore the ability to inject a UEFI payload into memory and `bootefi`
> it. If the address passed isn't the last PE-COFF loaded, then we'll
> wipe out the pre-existing DP/Image information and let efi_run_image()
> synthesize a memory device path.
>
> An image size is required if we're booting an arbitrary payload, and
> the FDT argument has been changed to accept `-`. The size could be
> deduced from the image header, but it's required anyways as an explicit
> acknowledgment that one's trying to boot an arbitrary payload rather
> than accidentally using the wrong address in the single-addr form.
The syntax seems to be odd and I don't think it is user-friendly
"<image address> [fdt address [image size]]\n"
as an image-related parameter,<image size>, doesn't follow <address>
immediately but comes *after* <fdt address>.
Instead, I would suggest
bootefi <image addr>[:<image size>] [<fdt addr>]
(or [<image size>@]<image addr>)
I believe that "<addr>:<size>" notation is quite intuitive and non-misleading.
Moreover, a similar syntax can be seen, for example, in booti command.
-Takahiro Akashi
> If the image address matches the last loaded PE_COFF, it is an error
> to pass the incorrect size (but the size may be omitted).
>
> Signed-off-by: Kyle Evans <kev...@freebsd.org>
> ---
>
> Changes since v1:
> - Specifying an address that isn't the last-known without a size produces the
> same error as in the past ("No UEFI binary known at ...")
> - Specifying a size with the last known address that doesn't match the last
> recorded size will get: Size does not match known UEFI binary at %s
>
> cmd/bootefi.c | 42 ++++++++++++++++++++++++++++++++++--------
> 1 file changed, 34 insertions(+), 8 deletions(-)
>
> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
> index 53d9f0e0dc..0d3aecb2a1 100644
> --- a/cmd/bootefi.c
> +++ b/cmd/bootefi.c
> @@ -425,7 +425,7 @@ static int do_efibootmgr(void)
> * @image_opt: string of image start address
> * Return: status code
> */
> -static int do_bootefi_image(const char *image_opt)
> +static int do_bootefi_image(const char *image_opt, const char *size_opt)
> {
> void *image_buf;
> unsigned long addr, size;
> @@ -444,13 +444,35 @@ static int do_bootefi_image(const char *image_opt)
> if (!addr)
> return CMD_RET_USAGE;
>
> + size = 0;
> + if (size_opt) {
> + size = strtoul(size_opt, NULL, 16);
> + /* Check that a numeric value was passed */
> + if (!size)
> + return CMD_RET_USAGE;
> + }
> +
> image_buf = map_sysmem(addr, 0);
>
> if (image_buf != image_addr) {
> - log_err("No UEFI binary known at %s\n", image_opt);
> - return CMD_RET_FAILURE;
> + /* Fake device path -- we must have a size. */
> +
> + if (size == 0) {
> + printf("No UEFI binary known at %s\n",
> image_opt);
> + return CMD_RET_FAILURE;
> + }
> +
> + if (image_addr)
> + efi_clear_bootdev();
> + } else {
> + if (size != 0 && size != image_size) {
> + printf("Size does not match known UEFI binary
> at %s\n",
> + image_opt);
> + return CMD_RET_FAILURE;
> + }
> +
> + size = image_size;
> }
> - size = image_size;
> }
> ret = efi_run_image(image_buf, size);
>
> @@ -654,7 +676,7 @@ static int do_bootefi(struct cmd_tbl *cmdtp, int flag,
> int argc,
> return CMD_RET_FAILURE;
> }
>
> - if (argc > 2) {
> + if (argc > 2 && strcmp(argv[2], "-") != 0) {
> uintptr_t fdt_addr;
>
> fdt_addr = hextoul(argv[2], NULL);
> @@ -677,15 +699,19 @@ static int do_bootefi(struct cmd_tbl *cmdtp, int flag,
> int argc,
> return do_efi_selftest();
> #endif
>
> - return do_bootefi_image(argv[1]);
> + return do_bootefi_image(argv[1], argc > 3 ? argv[3] : NULL);
> }
>
> #ifdef CONFIG_SYS_LONGHELP
> static char bootefi_help_text[] =
> - "<image address> [fdt address]\n"
> + "<image address> [fdt address [image size]]\n"
> " - boot EFI payload stored at address <image address>.\n"
> " If specified, the device tree located at <fdt address> gets\n"
> " exposed as EFI configuration table.\n"
> + " The image size is required if this is not a preloaded image, but\n"
> + " it must be omitted if the image was preloaded.\n"
> + " The <fdt address> parameter accepts '-' to indicate FDT already\n"
> + " installed or pre-specified in fdt_addr or fdtcontroladdr.\n"
> #ifdef CONFIG_CMD_BOOTEFI_HELLO
> "bootefi hello\n"
> " - boot a sample Hello World application stored within U-Boot\n"
> @@ -707,7 +733,7 @@ static char bootefi_help_text[] =
> #endif
>
> U_BOOT_CMD(
> - bootefi, 3, 0, do_bootefi,
> + bootefi, 4, 0, do_bootefi,
> "Boots an EFI payload from memory",
> bootefi_help_text
> );
> --
> 2.33.0
>
