Hi Ard,
> Given that GRUB now supports the native EFI entrypoint properly,
> the handover protocol is essentially deprecated.
In my case, the systemd-boot jumped into the EFI stub code via
handover protocol, this may not be an orthodox way to boot the kernel
but it performs well on the others, I have tested on at least
6 firmware.
I understand that the handover protocol is going to be deprecated.
However, as of now, I can't guarantee which EFI loader will be
used to load my bzImage. Although it’s not very common, booting
from the handover protocol with uncleaned BSS memory is possible.
>> memset(_bss+0x10000, 0, _ebss - _bss - 0x10000)
> So now you are applying the memset only to part of BSS, right? How
> does this help?
This part doesn't work without increasing the BOOT_STACK_SIZE.
And following content is my PE metadata, many thanks!
File: bzImage
Format: COFF-x86-64
Arch: x86_64
AddressSize: 64bit
ImageFileHeader {
Machine: IMAGE_FILE_MACHINE_AMD64 (0x8664)
SectionCount: 3
TimeDateStamp: 1970-01-01 00:00:00 (0x0)
PointerToSymbolTable: 0x0
SymbolCount: 0
StringTableSize: 0
OptionalHeaderSize: 160
Characteristics [ (0x206)
IMAGE_FILE_DEBUG_STRIPPED (0x200)
IMAGE_FILE_EXECUTABLE_IMAGE (0x2)
IMAGE_FILE_LINE_NUMS_STRIPPED (0x4)
]
}
ImageOptionalHeader {
Magic: 0x20B
MajorLinkerVersion: 2
MinorLinkerVersion: 20
SizeOfCode: 9416704
SizeOfInitializedData: 241664
SizeOfUninitializedData: 0
AddressOfEntryPoint: 0x8F8990
BaseOfCode: 0x4000
ImageBase: 0x0
SectionAlignment: 4096
FileAlignment: 512
MajorOperatingSystemVersion: 0
MinorOperatingSystemVersion: 0
MajorImageVersion: 3
MinorImageVersion: 0
MajorSubsystemVersion: 0
MinorSubsystemVersion: 0
SizeOfImage: 9674752
SizeOfHeaders: 4096
Subsystem: IMAGE_SUBSYSTEM_EFI_APPLICATION (0xA)
Characteristics [ (0x100)
IMAGE_DLL_CHARACTERISTICS_NX_COMPAT (0x100)
]
SizeOfStackReserve: 0
SizeOfStackCommit: 0
SizeOfHeapReserve: 0
SizeOfHeapCommit: 0
NumberOfRvaAndSize: 6
DataDirectory {
ExportTableRVA: 0x0
ExportTableSize: 0x0
ImportTableRVA: 0x0
ImportTableSize: 0x0
ResourceTableRVA: 0x0
ResourceTableSize: 0x0
ExceptionTableRVA: 0x0
ExceptionTableSize: 0x0
CertificateTableRVA: 0x0
CertificateTableSize: 0x0
BaseRelocationTableRVA: 0x0
BaseRelocationTableSize: 0x0
}
}
DOSHeader {
Magic: MZ
UsedBytesInTheLastPage: 0
FileSizeInPages: 0
NumberOfRelocationItems: 0
HeaderSizeInParagraphs: 0
MinimumExtraParagraphs: 0
MaximumExtraParagraphs: 0
InitialRelativeSS: 0
InitialSP: 0
Checksum: 0
InitialIP: 0
InitialRelativeCS: 0
AddressOfRelocationTable: 0
OverlayNumber: 0
OEMid: 0
OEMinfo: 0
AddressOfNewExeHeader: 64
}
Sections [
Section {
Number: 1
Name: .setup (2E 73 65 74 75 70 00 00)
VirtualSize: 0x3000
VirtualAddress: 0x1000
RawDataSize: 12288
PointerToRawData: 0x1000
PointerToRelocations: 0x0
PointerToLineNumbers: 0x0
RelocationCount: 0
LineNumberCount: 0
Characteristics [ (0x42000040)
IMAGE_SCN_CNT_INITIALIZED_DATA (0x40)
IMAGE_SCN_MEM_DISCARDABLE (0x2000000)
IMAGE_SCN_MEM_READ (0x40000000)
]
}
Section {
Number: 2
Name: .text (2E 74 65 78 74 00 00 00)
VirtualSize: 0x8FB000
VirtualAddress: 0x4000
RawDataSize: 9416704
PointerToRawData: 0x4000
PointerToRelocations: 0x0
PointerToLineNumbers: 0x0
RelocationCount: 0
LineNumberCount: 0
Characteristics [ (0x60000020)
IMAGE_SCN_CNT_CODE (0x20)
IMAGE_SCN_MEM_EXECUTE (0x20000000)
IMAGE_SCN_MEM_READ (0x40000000)
]
}
Section {
Number: 3
Name: .data (2E 64 61 74 61 00 00 00)
VirtualSize: 0x3B000
VirtualAddress: 0x8FF000
RawDataSize: 1024
PointerToRawData: 0x8FF000
PointerToRelocations: 0x0
PointerToLineNumbers: 0x0
RelocationCount: 0
LineNumberCount: 0
Characteristics [ (0xC0000040)
IMAGE_SCN_CNT_INITIALIZED_DATA (0x40)
IMAGE_SCN_MEM_READ (0x40000000)
IMAGE_SCN_MEM_WRITE (0x80000000)
]
}
]
Relocations [
]
UnwindInformation [
]
Symbols [
]
