[PATCH 1/1] efi_loader: find distro device-path for media devices

[Heinrich Schuchardt]

The auto-generated load options for media device do not contain a partition
node. We cannot expect the simple file protocol here.

Get the partition device-path via the loaded image protocol.

Fixes: e91b68fd6b83 ("efi_loader: load distro dtb in bootmgr")
Reported-by: E Shattow <luc...@gmail.com>
Signed-off-by: Heinrich Schuchardt <heinrich.schucha...@canonical.com>
---
 include/efi_loader.h         |  2 +-
 lib/efi_loader/efi_bootmgr.c |  2 +-
 lib/efi_loader/efi_fdt.c     | 33 +++++++++++++++++++--------------
 3 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/include/efi_loader.h b/include/efi_loader.h
index 6c993e1a694..2a06fbe4704 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -1205,6 +1205,6 @@ efi_status_t efi_load_option_dp_join(struct 
efi_device_path **dp,
 
 int efi_get_distro_fdt_name(char *fname, int size, int seq);
 
-void efi_load_distro_fdt(void **fdt, efi_uintn_t *fdt_size);
+void efi_load_distro_fdt(efi_handle_t handle, void **fdt, efi_uintn_t 
*fdt_size);
 
 #endif /* _EFI_LOADER_H */
diff --git a/lib/efi_loader/efi_bootmgr.c b/lib/efi_loader/efi_bootmgr.c
index 304ed43595c..589d3996b68 100644
--- a/lib/efi_loader/efi_bootmgr.c
+++ b/lib/efi_loader/efi_bootmgr.c
@@ -1277,7 +1277,7 @@ efi_status_t efi_bootmgr_run(void *fdt)
                if (fdt_lo)
                        fdt = fdt_lo;
                if (!fdt) {
-                       efi_load_distro_fdt(&fdt_distro, &fdt_size);
+                       efi_load_distro_fdt(handle, &fdt_distro, &fdt_size);
                        fdt = fdt_distro;
                }
        }
diff --git a/lib/efi_loader/efi_fdt.c b/lib/efi_loader/efi_fdt.c
index 86ba00c2bdd..4ccf2055be3 100644
--- a/lib/efi_loader/efi_fdt.c
+++ b/lib/efi_loader/efi_fdt.c
@@ -75,28 +75,34 @@ int efi_get_distro_fdt_name(char *fname, int size, int seq)
 /**
  * efi_load_distro_fdt() - load distro device-tree
  *
+ * @handle:    handle of loaded image
  * @fdt:       on return device-tree, must be freed via efi_free_pages()
  * @fdt_size:  buffer size
  */
-void efi_load_distro_fdt(void **fdt, efi_uintn_t *fdt_size)
+void efi_load_distro_fdt(efi_handle_t handle, void **fdt, efi_uintn_t 
*fdt_size)
 {
-       struct efi_device_path *rem, *dp;
+       struct efi_device_path *dp;
        efi_status_t  ret;
+       struct efi_handler *handler;
+       struct efi_loaded_image *loaded_image;
        efi_handle_t device;
 
        *fdt = NULL;
 
-       dp = efi_get_dp_from_boot(NULL);
-       if (!dp)
+       /* Get boot device from loaded image protocol */
+       ret = efi_search_protocol(handle, &efi_guid_loaded_image, &handler);
+       if (ret != EFI_SUCCESS)
                return;
-       device = efi_dp_find_obj(dp, NULL, &rem);
-       ret = efi_search_protocol(device, &efi_simple_file_system_protocol_guid,
-                                 NULL);
+       loaded_image = handler->protocol_interface;
+       device = loaded_image->device_handle;
+
+       /* Get device path of boot device */
+       ret = efi_search_protocol(device, &efi_guid_device_path, &handler);
        if (ret != EFI_SUCCESS)
-               goto err;
-       memcpy(rem, &END, sizeof(END));
+               return;
+       dp = handler->protocol_interface;
 
-       /* try the various available names */
+       /* Try the various available names */
        for (int seq = 0; ; ++seq) {
                struct efi_device_path *file;
                char buf[255];
@@ -108,10 +114,9 @@ void efi_load_distro_fdt(void **fdt, efi_uintn_t *fdt_size)
                        break;
                ret = efi_load_image_from_path(true, file, fdt, fdt_size);
                efi_free_pool(file);
-               if (ret == EFI_SUCCESS)
+               if (ret == EFI_SUCCESS) {
+                       log_debug("Fdt %pD loaded\n", file);
                        break;
+               }
        }
-
-err:
-       efi_free_pool(dp);
 }
-- 
2.45.2