This is my flavor of OVMF: build -p OvmfPkg/OvmfPkgX64.dsc -a X64 -t XCODE5 It looks like I took an exception? Is it expected that an unhandled exception just hang in a dead loop? I would have expected some serial output about the failure? Looks like a divide by zero exception. The exception context has PC and FP so I can manually walk the stack. Yikes I see PlatformBootManagerWaitCallback() will fault if PcdPlatformBootTimeOut is zero? /Volumes/Case/UDK2018(master)>git grep PcdPlatformBootTimeOut -- *.dsc ArmVirtPkg/ArmVirtQemu.dsc:194: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|3 ArmVirtPkg/ArmVirtQemuKernel.dsc:191: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|3 ArmVirtPkg/ArmVirtXen.dsc:122: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|3 EmulatorPkg/EmulatorPkg.dsc:236: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|L"Timeout"|gEfiGlobalVariableGuid|0x0|10 OvmfPkg/OvmfPkgIa32.dsc:541: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|0 OvmfPkg/OvmfPkgIa32X64.dsc:553: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|0 OvmfPkg/OvmfPkgX64.dsc:552: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|0 OvmfPkg/OvmfXen.dsc:470: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|0 UefiPayloadPkg/UefiPayloadPkgIa32.dsc:344: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|3 UefiPayloadPkg/UefiPayloadPkgIa32X64.dsc:345: gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|3 OK PcdPlatformBootTimeOut is zero on Ovmf, so how did this ever work? Ahhh gotom.... /Volumes/Case/UDK2018(master)>git blame -L344,344 /Volumes/Case/UDK2018/MdeModulePkg/Universal/BdsDxe/BdsEntry.c 2de1f611be0 (Pete Batard 2019-09-25 23:50:05 +0800 344) PlatformBootManagerWaitCallback (0); This call causes a divide by zero if PcdPlatformBootTimeOut == 0. This fixes my crash: diff --git a/OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c b/OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c index 70df6b841a..d6ae43e900 100644 --- a/OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c +++ b/OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c @@ -1634,6 +1634,11 @@ PlatformBootManagerWaitCallback ( UINT16 Timeout; Timeout = PcdGet16 (PcdPlatformBootTimeOut); + if (Timeout == 0) { + Timeout = 100; + } else { + Timeout = (Timeout - TimeoutRemain) * 100 / Timeout; + } Black.Raw = 0x00000000; White.Raw = 0x00FFFFFF; @@ -1643,7 +1648,7 @@ PlatformBootManagerWaitCallback ( Black.Pixel, L"Start boot option", White.Pixel, - (Timeout - TimeoutRemain) * 100 / Timeout, + Timeout, 0 ); } lldb debugger output: (lldb) bt * thread #1, stop reason = signal SIGTRAP * frame #0: 0x0000000007b58a70 CpuDxe.dll:CpuDeadLoop() + 13 at /Volumes/Case/UDK2018/MdePkg/Library/BaseLib/CpuDeadLoop.c:31 frame #1: 0x0000000007b61222 CpuDxe.dll:CommonExceptionHandlerWorker() + 674 at /Volumes/Case/UDK2018/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiDxeSmmCpuException.c:115 frame #2: 0x0000000007b61624 CpuDxe.dll:CommonExceptionHandler() + 36 at /Volumes/Case/UDK2018/UefiCpuPkg/Library/CpuExceptionHandlerLib/DxeException.c:40 frame #3: 0x0000000007b5ff26 CpuDxe.dll:HasErrorCode() + 230 (lldb) fr sel 1 frame #1: 0x0000000007b61222 CpuDxe.dll:CommonExceptionHandlerWorker() + 674 at /Volumes/Case/UDK2018/UefiCpuPkg/Library/CpuExceptionHandlerLib/PeiDxeSmmCpuException.c:115 91 (ExternalInterruptHandler[ExceptionType]) (ExceptionType, SystemContext); 92 } else if (ExceptionType < CPU_EXCEPTION_NUM) { 93 // 94 // Get Spinlock to display CPU information 95 // 96 while (!AcquireSpinLockOrFail (&ExceptionHandlerData->DisplayMessageSpinLock)) { 97 CpuPause (); 98 } 99 // 100 // Initialize the serial port before dumping. 101 // 102 SerialPortInitialize (); 103 // 104 // Display ExceptionType, CPU information and Image information 105 // 106 DumpImageAndCpuContent (ExceptionType, SystemContext); 107 // 108 // Release Spinlock of output message 109 // 110 ReleaseSpinLock (&ExceptionHandlerData->DisplayMessageSpinLock); 111 // 112 // Enter a dead loop if needn't to execute old IDT handler further 113 // 114 if (ReservedVectors[ExceptionType].Attribute != EFI_VECTOR_HANDOFF_HOOK_BEFORE) { -> 115 CpuDeadLoop (); 116 } 117 } 118 } 119 (lldb) p ExceptionType (EFI_EXCEPTION_TYPE) $0 = 0 (lldb) p SystemContext.SystemContextX64->Rip (UINT64) $1 = 0x0000000007a9cc38 (lldb) p SystemContext.SystemContextX64->Rbp (UINT64) $2 = 0x0000000007e8fc20 (lldb) efi_backtrace --pc 0x0000000007a9cc38 --frame 0x0000000007e8fc20 --symbols frame 0: 0x07a9cc38 BdsDxe:PlatformBootManagerWaitCallback + 35 at /Volumes/Case/UDK2018/OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c:1646:37 frame 1: 0x07a9e744 BdsDxe:BdsWait + 269 at /Volumes/Case/UDK2018/MdeModulePkg/Universal/BdsDxe/BdsEntry.c:344:3 frame 2: 0x07a9dff9 BdsDxe:BdsEntry + 2620 at /Volumes/Case/UDK2018/MdeModulePkg/Universal/BdsDxe/BdsEntry.c:1002:5 frame 3: 0x07eb367d DxeCore:DxeMain + 2680 at /Volumes/Case/UDK2018/MdeModulePkg/Core/Dxe/DxeMain/DxeMain.c:544:3 frame 4: 0x07e943cb DxeCore:_ModuleEntryPoint + 20 at /Volumes/Case/UDK2018/MdePkg/Library/DxeCoreEntryPoint/DxeCoreEntryPoint.c:48:3 frame 5: 0x07edc947 DxeIpl.dll`AsmEnableCache frame 6: 0x07ee1e4e DxeIpl:HandOffToDxeCore + 509 at /Volumes/Case/UDK2018/MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c:113:3 frame 7: 0x07ee0604 DxeIpl:DxeLoadCore + 1354 at /Volumes/Case/UDK2018/MdeModulePkg/Core/DxeIplPeim/DxeLoad.c:449:3 frame 8: 0x07eeff2f PeiCore.dll`PeiCore.cold.3 + 847 frame 9: 0x07ee9d04 PeiCore:PeiCore + 163 at /Volumes/Case/UDK2018/MdeModulePkg/Core/Pei/PeiMain/PeiMain.c:502:3 frame 10: 0x0082c387 0x0082c387 frame 11: 0x00825dd7 0x00825dd7 frame 12: 0x0082ad27 0x0082ad27 frame 13: 0x0082b3a8 0x0082b3a8 frame 14: 0x0082bf23 0x0082bf23 frame 15: 0x00825e24 0x00825e24 frame 16: 0x00823af2 0x00823af2 frame 17: 0xfffd1db8 SecMain:SecStartupPhase2 + 67 at /Volumes/Case/UDK2018/OvmfPkg/Sec/SecMain.c:858:3 frame 18: 0xfffd1d67 SecMain:SecCoreStartupWithStack + 420 at /Volumes/Case/UDK2018/OvmfPkg/Sec/SecMain.c:821:3 frame 19: 0xfffd1e14 SecMain:ProcessLibraryConstructorList + 0 at /Volumes/Case/UDK2018/Build/OvmfX64/DEBUG_XCODE5/X64/OvmfPkg/Sec/SecMain/DEBUG/AutoGen.c:201 (lldb) l /Volumes/Case/UDK2018/OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c:1646 1646 (Timeout - TimeoutRemain) * 100 / Timeout, 1647 0 1648 ); 1649 } 1650 1651 /** 1652 The function is called when no boot option could be launched, 1653 including platform recovery options and options pointing to applications 1654 built into firmware volumes. 1655 (lldb) l /Volumes/Case/UDK2018/MdeModulePkg/Universal/BdsDxe/BdsEntry.c:344 344 PlatformBootManagerWaitCallback (0); 345 DEBUG ((EFI_D_INFO, "[Bds]Exit the waiting!\n")); 346 } 347 348 /** 349 Attempt to boot each boot option in the BootOptions array. 350 351 @param BootOptions Input boot option array. 352 @param BootOptionCount Input boot option count. 353 @param BootManagerMenu Input boot manager menu. 354 Thanks, Andrew Fish