From 0e6584e38650cef9a6b4579553679c0f12d897bc Mon Sep 17 00:00:00 2001 From: Ruiyu Ni Date: Thu, 28 Sep 2017 13:46:20 +0800 Subject: [PATCH] MdeModulePkg/BdsDxe: Don't delete "BootNext" until booting it Current implementation deletes the "BootNext" before calling any PlatformBootManagerLib APIs, but if system resets in PlatformBootManagerLib APIs, "BootNext" is not consumed but lost. The patch defers the deletion of "BootNext" to before booting it. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ruiyu Ni Cc: Eric Dong Reviewed-by: Star Zeng Reviewed-by: Sunny Wang --- MdeModulePkg/Universal/BdsDxe/BdsEntry.c | 35 ++++++++++++++---------- 1 file changed, 20 insertions(+), 15 deletions(-) diff --git a/MdeModulePkg/Universal/BdsDxe/BdsEntry.c b/MdeModulePkg/Universal/BdsDxe/BdsEntry.c index ac5f9088dd..a6fe617b56 100644 --- a/MdeModulePkg/Universal/BdsDxe/BdsEntry.c +++ b/MdeModulePkg/Universal/BdsDxe/BdsEntry.c @@ -808,7 +808,8 @@ BdsEntry ( ASSERT_EFI_ERROR (Status); // - // Cache and remove the "BootNext" NV variable. + // Cache the "BootNext" NV variable before calling any PlatformBootManagerLib APIs + // This could avoid the "BootNext" set by PlatformBootManagerLib be consumed in this boot. // GetEfiGlobalVariable2 (EFI_BOOT_NEXT_VARIABLE_NAME, (VOID **) &BootNext, &DataSize); if (DataSize != sizeof (UINT16)) { @@ -817,17 +818,6 @@ BdsEntry ( } BootNext = NULL; } - Status = gRT->SetVariable ( - EFI_BOOT_NEXT_VARIABLE_NAME, - &gEfiGlobalVariableGuid, - 0, - 0, - NULL - ); - // - // Deleting NV variable shouldn't fail unless it doesn't exist. - // - ASSERT (Status == EFI_SUCCESS || Status == EFI_NOT_FOUND); // // Initialize the platform language variables @@ -1052,10 +1042,25 @@ BdsEntry ( EfiBootManagerHotkeyBoot (); - // - // Boot to "BootNext" - // if (BootNext != NULL) { + // + // Delete "BootNext" NV variable before transferring control to it to prevent loops. + // + Status = gRT->SetVariable ( + EFI_BOOT_NEXT_VARIABLE_NAME, + &gEfiGlobalVariableGuid, + 0, + 0, + NULL + ); + // + // Deleting NV variable shouldn't fail unless it doesn't exist. + // + ASSERT (Status == EFI_SUCCESS || Status == EFI_NOT_FOUND); + + // + // Boot to "BootNext" + // UnicodeSPrint (BootNextVariableName, sizeof (BootNextVariableName), L"Boot%04x", *BootNext); Status = EfiBootManagerVariableToLoadOption (BootNextVariableName, &LoadOption); if (!EFI_ERROR (Status)) { -- 2.39.2