On Sat, Feb 26, 2022 at 12:56:51PM +0100, Heinrich Schuchardt wrote: > The GUID of partitions is sufficient for identification and will stay > constant in the lifetime of a boot option. The preceding path of the > device-path may change due to changes in the enumeration of devices. > Therefore it is preferable to use the short-form of device-paths in load > options. Adjust the 'efidebug boot add' command accordingly.
Since a "long" device path is still valid, I think that a user should be allowed to use a long device path especially if he or she wants to limit an interface for loading any image. Please add an option to efidebug to select a short or long path. Furthermore, I would like to ask you to add a test, as you always require me to do so, for loading from a short path. Otherwise, the feature will never be exercised in CI loop. -Takahiro Akashi > Signed-off-by: Heinrich Schuchardt <[email protected]> > --- > cmd/efidebug.c | 15 +++++++++++---- > include/efi_loader.h | 3 ++- > lib/efi_loader/efi_device_path.c | 21 +++++++++++++-------- > 3 files changed, 26 insertions(+), 13 deletions(-) > > diff --git a/cmd/efidebug.c b/cmd/efidebug.c > index 401d13cc4c..f62a4345fd 100644 > --- a/cmd/efidebug.c > +++ b/cmd/efidebug.c > @@ -747,7 +747,7 @@ struct efi_device_path *create_initrd_dp(const char *dev, > const char *part, > const char *file) > > { > - struct efi_device_path *tmp_dp = NULL, *tmp_fp = NULL; > + struct efi_device_path *tmp_dp = NULL, *tmp_fp = NULL, *short_fp; > struct efi_device_path *initrd_dp = NULL; > efi_status_t ret; > const struct efi_initrd_dp id_dp = { > @@ -771,9 +771,12 @@ struct efi_device_path *create_initrd_dp(const char > *dev, const char *part, > printf("Cannot create device path for \"%s %s\"\n", part, file); > goto out; > } > + short_fp = efi_dp_shorten(tmp_fp); > + if (!short_fp) > + short_fp = tmp_fp; > > initrd_dp = efi_dp_append((const struct efi_device_path *)&id_dp, > - tmp_fp); > + short_fp); > > out: > efi_free_pool(tmp_dp); > @@ -807,6 +810,7 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int > flag, > size_t label_len, label_len16; > u16 *label; > struct efi_device_path *device_path = NULL, *file_path = NULL; > + struct efi_device_path *fp_free = NULL; > struct efi_device_path *final_fp = NULL; > struct efi_device_path *initrd_dp = NULL; > struct efi_load_option lo; > @@ -849,13 +853,16 @@ static int do_efi_boot_add(struct cmd_tbl *cmdtp, int > flag, > > /* file path */ > ret = efi_dp_from_name(argv[3], argv[4], argv[5], > - &device_path, &file_path); > + &device_path, &fp_free); > if (ret != EFI_SUCCESS) { > printf("Cannot create device path for \"%s > %s\"\n", > argv[3], argv[4]); > r = CMD_RET_FAILURE; > goto out; > } > + file_path = efi_dp_shorten(fp_free); > + if (!file_path) > + file_path = fp_free; > fp_size += efi_dp_size(file_path) + > sizeof(struct efi_device_path); > argc -= 5; > @@ -927,7 +934,7 @@ out: > efi_free_pool(final_fp); > efi_free_pool(initrd_dp); > efi_free_pool(device_path); > - efi_free_pool(file_path); > + efi_free_pool(fp_free); > free(lo.label); > > return r; > diff --git a/include/efi_loader.h b/include/efi_loader.h > index e390d323a9..c7d6b7c7f3 100644 > --- a/include/efi_loader.h > +++ b/include/efi_loader.h > @@ -725,7 +725,8 @@ extern void *efi_bounce_buffer; > #define EFI_LOADER_BOUNCE_BUFFER_SIZE (64 * 1024 * 1024) > #endif > > - > +/* shorten device path */ > +struct efi_device_path *efi_dp_shorten(struct efi_device_path *dp); > struct efi_device_path *efi_dp_next(const struct efi_device_path *dp); > int efi_dp_match(const struct efi_device_path *a, > const struct efi_device_path *b); > diff --git a/lib/efi_loader/efi_device_path.c > b/lib/efi_loader/efi_device_path.c > index dc787b4d3d..ddd5f132ec 100644 > --- a/lib/efi_loader/efi_device_path.c > +++ b/lib/efi_loader/efi_device_path.c > @@ -122,20 +122,25 @@ int efi_dp_match(const struct efi_device_path *a, > } > } > > -/* > +/** > + * efi_dp_shorten() - shorten device-path > + * > * We can have device paths that start with a USB WWID or a USB Class node, > * and a few other cases which don't encode the full device path with bus > * hierarchy: > * > - * - MESSAGING:USB_WWID > - * - MESSAGING:USB_CLASS > - * - MEDIA:FILE_PATH > - * - MEDIA:HARD_DRIVE > - * - MESSAGING:URI > + * * MESSAGING:USB_WWID > + * * MESSAGING:USB_CLASS > + * * MEDIA:FILE_PATH > + * * MEDIA:HARD_DRIVE > + * * MESSAGING:URI > * > * See UEFI spec (section 3.1.2, about short-form device-paths) > + * > + * @dp: original devie-path > + * @Return: shortened device-path or NULL > */ > -static struct efi_device_path *shorten_path(struct efi_device_path *dp) > +struct efi_device_path *efi_dp_shorten(struct efi_device_path *dp) > { > while (dp) { > /* > @@ -189,7 +194,7 @@ static struct efi_object *find_obj(struct efi_device_path > *dp, bool short_path, > } > } > > - obj_dp = shorten_path(efi_dp_next(obj_dp)); > + obj_dp = efi_dp_shorten(efi_dp_next(obj_dp)); > } while (short_path && obj_dp); > } > > -- > 2.34.1 >
