From 1b6c3a94eca7f12f6a3b65a3e8619d2e2e7c1eb6 Mon Sep 17 00:00:00 2001 From: Leif Lindholm Date: Thu, 4 Feb 2021 12:36:59 +0000 Subject: [PATCH] ArmPkg/Library: prevent endless reboot loop with emulated NV varstore If no valid boot options were found, PlatformBootManagerLib refreshes a set of sane default options and then reboots. However, if there is in fact no persistent varstore, the same thing happens again on next boot, and we end up in an endlessly rebooting loop. So when PcdEmuVariableNvModeEnable is TRUE, skip the reboot step and enter the setup menu instead. Cc: Ard Biesheuvel Cc: Laszlo Ersek Signed-off-by: Leif Lindholm Acked-by: Laszlo Ersek Reviewed-by: Ard Biesheuvel --- ArmPkg/Library/PlatformBootManagerLib/PlatformBm.c | 12 ++++++++---- .../PlatformBootManagerLib.inf | 1 + 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/ArmPkg/Library/PlatformBootManagerLib/PlatformBm.c b/ArmPkg/Library/PlatformBootManagerLib/PlatformBm.c index 9905cad229..5ceb23d822 100644 --- a/ArmPkg/Library/PlatformBootManagerLib/PlatformBm.c +++ b/ArmPkg/Library/PlatformBootManagerLib/PlatformBm.c @@ -848,11 +848,15 @@ PlatformBootManagerUnableToBoot ( // If the number of configured boot options has changed, reboot // the system so the new boot options will be taken into account // while executing the ordinary BDS bootflow sequence. + // *Unless* persistent varstore is being emulated, since we would + // then end up in an endless reboot loop. // - if (NewBootOptionCount != OldBootOptionCount) { - DEBUG ((DEBUG_WARN, "%a: rebooting after refreshing all boot options\n", - __FUNCTION__)); - gRT->ResetSystem (EfiResetCold, EFI_SUCCESS, 0, NULL); + if (!PcdGetBool (PcdEmuVariableNvModeEnable)) { + if (NewBootOptionCount != OldBootOptionCount) { + DEBUG ((DEBUG_WARN, "%a: rebooting after refreshing all boot options\n", + __FUNCTION__)); + gRT->ResetSystem (EfiResetCold, EFI_SUCCESS, 0, NULL); + } } Status = EfiBootManagerGetBootManagerMenu (&BootManagerMenu); diff --git a/ArmPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf b/ArmPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf index 2f726d117d..353d7a967b 100644 --- a/ArmPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf +++ b/ArmPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf @@ -55,6 +55,7 @@ gEfiMdePkgTokenSpaceGuid.PcdUgaConsumeSupport [FixedPcd] + gEfiMdeModulePkgTokenSpaceGuid.PcdEmuVariableNvModeEnable gEfiMdeModulePkgTokenSpaceGuid.PcdFirmwareVersionString gEfiMdePkgTokenSpaceGuid.PcdUartDefaultBaudRate gEfiMdePkgTokenSpaceGuid.PcdUartDefaultDataBits -- 2.39.2