From a046da21a4c58365be6c029147799db974280048 Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Mon, 22 Nov 2021 12:50:38 +0000 Subject: [PATCH] [efi] Raise TPL during driver unload entry point The efi_unload() function is currently missing the calls to raise and restore the TPL. This has the side effect of causing iPXE to return from the driver unload entry point at TPL_CALLBACK, which will cause unexpected behaviour (typically a system lockup) shortly afterwards. Fix by adding the missing calls to raise and restore the TPL. Debugged-by: Petr Borsodi Signed-off-by: Michael Brown --- src/interface/efi/efi_init.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/src/interface/efi/efi_init.c b/src/interface/efi/efi_init.c index b7cac16e5..1c6e9d440 100644 --- a/src/interface/efi/efi_init.c +++ b/src/interface/efi/efi_init.c @@ -316,9 +316,13 @@ EFI_STATUS efi_init ( EFI_HANDLE image_handle, static EFI_STATUS EFIAPI efi_unload ( EFI_HANDLE image_handle __unused ) { EFI_BOOT_SERVICES *bs = efi_systab->BootServices; EFI_SYSTEM_TABLE *systab = efi_systab; + struct efi_saved_tpl tpl; DBGC ( systab, "EFI image unloading\n" ); + /* Raise TPL */ + efi_raise_tpl ( &tpl ); + /* Shut down */ shutdown_exit(); @@ -336,6 +340,9 @@ static EFI_STATUS EFIAPI efi_unload ( EFI_HANDLE image_handle __unused ) { DBGC ( systab, "EFI image unloaded\n" ); + /* Restore TPL */ + efi_restore_tpl ( &tpl ); + return 0; }