[efi] Ensure that all drivers are shut down before the OS boots

Reported-by: Itay Gazit <itayg@mellanox.co.il>
Suggested-by: Michael R Turner <mikeyt@us.ibm.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/image/efi_image.c

@@ -26,20 +26,6 @@ FILE_LICENCE ( GPL2_OR_LATER );
 
 FEATURE ( FEATURE_IMAGE, "EFI", DHCP_EB_FEATURE_EFI, 1 );
 
-/** Event used to signal shutdown */
-static EFI_EVENT efi_shutdown_event;
-
-/**
- * Shut down in preparation for booting an OS.
- *
- * This hook gets called at ExitBootServices time in order to make sure that
- * the network cards are properly shut down before the OS takes over.
- */
-static EFIAPI void efi_shutdown_hook ( EFI_EVENT event __unused,
-				       void *context __unused ) {
-	shutdown_boot();
-}
-
 /**
  * Execute EFI image
  *
@@ -64,30 +50,14 @@ static int efi_image_exec ( struct image *image ) {
 		return -ENOEXEC;
 	}
 
-	/* Be sure to shut down the NIC at ExitBootServices time, or else
-	 * DMA from the card can corrupt the OS.
-	 */
-	efirc = bs->CreateEvent ( EVT_SIGNAL_EXIT_BOOT_SERVICES,
-				  TPL_CALLBACK, efi_shutdown_hook,
-				  NULL, &efi_shutdown_event );
-	if ( efirc ) {
-		rc = EFIRC_TO_RC ( efirc );
-		goto done;
-	}
-
 	/* Start the image */
 	if ( ( efirc = bs->StartImage ( handle, &exit_data_size,
 					&exit_data ) ) != 0 ) {
 		DBGC ( image, "EFIIMAGE %p returned with status %s\n",
 		       image, efi_strerror ( efirc ) );
 	}
-
 	rc = EFIRC_TO_RC ( efirc );
 
-	/* Remove the shutdown hook */
-	bs->CloseEvent ( efi_shutdown_event );
-
-done:
 	/* Unload the image.  We can't leave it loaded, because we
 	 * have no "unload" operation.
 	 */

src/interface/efi/efi_init.c

@@ -22,6 +22,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #include <ipxe/efi/efi.h>
 #include <ipxe/efi/Protocol/LoadedImage.h>
 #include <ipxe/uuid.h>
+#include <ipxe/init.h>
 
 /** Image handle passed to entry point */
 EFI_HANDLE efi_image_handle;
@@ -36,6 +37,21 @@ EFI_SYSTEM_TABLE *efi_systab;
 static EFI_GUID efi_loaded_image_protocol_guid
 	= EFI_LOADED_IMAGE_PROTOCOL_GUID;
 
+/** Event used to signal shutdown */
+static EFI_EVENT efi_shutdown_event;
+
+/**
+ * Shut down in preparation for booting an OS.
+ *
+ * This hook gets called at ExitBootServices time in order to make
+ * sure that everything is properly shut down before the OS takes
+ * over.
+ */
+static EFIAPI void efi_shutdown_hook ( EFI_EVENT event __unused,
+				       void *context __unused ) {
+	shutdown_boot();
+}
+
 /**
  * Look up EFI configuration table
  *
@@ -129,5 +145,18 @@ EFI_STATUS efi_init ( EFI_HANDLE image_handle,
 		}
 	}
 
+	/* EFI is perfectly capable of gracefully shutting down any
+	 * loaded devices if it decides to fall back to a legacy boot.
+	 * For no particularly comprehensible reason, it doesn't
+	 * bother doing so when ExitBootServices() is called.
+	 */
+	if ( ( efirc = bs->CreateEvent ( EVT_SIGNAL_EXIT_BOOT_SERVICES,
+					 TPL_CALLBACK, efi_shutdown_hook,
+					 NULL, &efi_shutdown_event ) ) != 0 ) {
+		DBGC ( systab, "EFI could not create ExitBootServices event: "
+		       "%s\n", efi_strerror ( efirc ) );
+		return efirc;
+	}
+
 	return 0;
 }

src/interface/efi/efi_pci.c

@@ -489,7 +489,7 @@ static struct efi_driver efipci_driver =
  * Install EFI PCI driver
  *
  */
-static void efipci_driver_init ( void ) {
+static void efipci_driver_startup ( void ) {
 	struct efi_driver *efidrv = &efipci_driver;
 	EFI_STATUS efirc;
 
@@ -503,7 +503,27 @@ static void efipci_driver_init ( void ) {
 	DBGC ( efidrv, "EFIPCI driver installed\n" );
 }
 
+/**
+ * Shut down EFI PCI driver
+ *
+ * @v booting		System is shutting down for OS boot
+ */
+static void efipci_driver_shutdown ( int booting __unused ) {
+	struct efi_driver *efidrv = &efipci_driver;
+	struct efi_pci_device *efipci;
+	struct efi_pci_device *tmp;
+
+	/* Shut down any remaining devices */
+	list_for_each_entry_safe ( efipci, tmp, &efi_pci_devices, list ) {
+		DBGC ( efipci, "EFIPCI " PCI_FMT " still active at shutdown; "
+		       "forcing close\n", PCI_ARGS ( &efipci->pci ) );
+		pci_remove ( &efipci->pci );
+		efipci_destroy ( efidrv, efipci );
+	}
+}
+
 /** EFI PCI startup function */
 struct startup_fn startup_pci __startup_fn ( STARTUP_NORMAL ) = {
-	.startup = efipci_driver_init,
+	.startup = efipci_driver_startup,
+	.shutdown = efipci_driver_shutdown,
 };