resolve: always read /etc/resolv.conf on reload systemd-resolved

When systemd-resolved is used in resolv.conf foreign mode, reloading the
systemd-resolved daemon does not read resolv.conf when not touched since
the last time resolved read the file. Since the DNS servers list is
flushed during a reload, resolved forgets about the servers
in /etc/resolv.conf

When reloading the daemon it is expected that all configuration is
reloaded regardless of the disk timestamps.

src/boot/boot.c

@@ -2443,12 +2443,6 @@ static EFI_STATUS initrd_prepare(
         size_t size = 0, padded_size = 0;
 
         STRV_FOREACH(i, entry->initrd) {
-                _cleanup_free_ char16_t *o = options;
-                if (o)
-                        options = xasprintf("%ls initrd=%ls", o, *i);
-                else
-                        options = xasprintf("initrd=%ls", *i);
-
                 _cleanup_file_close_ EFI_FILE *handle = NULL;
                 err = root->Open(root, &handle, *i, EFI_FILE_MODE_READ, 0);
                 if (err != EFI_SUCCESS)
@@ -2459,6 +2453,15 @@ static EFI_STATUS initrd_prepare(
                 if (err != EFI_SUCCESS)
                         return err;
 
+                if (info->FileSize == 0) /* Automatically skip over empty files */
+                        continue;
+
+                _cleanup_free_ char16_t *o = options;
+                if (o)
+                        options = xasprintf("%ls initrd=%ls", o, *i);
+                else
+                        options = xasprintf("initrd=%ls", *i);
+
                 size_t inc = info->FileSize;
 
                 if (!INC_SAFE(&padded_size, ALIGN4(inc)))
@@ -2466,6 +2469,14 @@ static EFI_STATUS initrd_prepare(
                 assert_se(INC_SAFE(&size, *(i + 1) ? ALIGN4(inc) : inc));
         }
 
+        /* Skip if no valid initrd files */
+        if (padded_size == 0) {
+                *ret_options = NULL;
+                *ret_initrd_pages = (Pages) {};
+                *ret_initrd_size = 0;
+                return EFI_SUCCESS;
+        }
+
         _cleanup_pages_ Pages pages = xmalloc_initrd_pages(padded_size);
         uint8_t *p = PHYSICAL_ADDRESS_TO_POINTER(pages.addr);
 

src/resolve/resolved-manager.c

@@ -641,6 +641,7 @@ static void manager_set_defaults(Manager *m) {
         m->cache_from_localhost = false;
         m->stale_retention_usec = 0;
         m->refuse_record_types = set_free(m->refuse_record_types);
+        m->resolv_conf_stat = (struct stat) {};
 }
 
 static int manager_dispatch_reload_signal(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {