Hello there,
in my last question I mentioned the x64 exception from QEMU.
I tried to solve it by myself, but it still does not work. But, at least, I think I found the cause: the entry of the kernel (ELF) binary is zero.
Below is the output of llvm-readelf:
ELF Header:
Magic: 7f 45 4c 46 02 01 01 00 00 00 00 00 00 00 00 00
Class: ELF64
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: EXEC (Executable file)
Machine: Advanced Micro Devices X86-64
Version: 0x1
Entry point address: 0x0
Start of program headers: 64 (bytes into file)
Start of section headers: 24344 (bytes into file)
Flags: 0x0
Size of this header: 64 (bytes)
Size of program headers: 56 (bytes)
Number of program headers: 4
Size of section headers: 64 (bytes)
Number of section headers: 18
Section header string table index: 16
There are 18 section headers, starting at offset 0x5f18:
Section Headers:
[Nr] Name Type Address Off Size ES Flg Lk Inf Al
[ 0] NULL 0000000000000000 000000 000000 00 0 0 0
[ 1] .text PROGBITS 0000000000100000 001000 0006a6 00 AX 0 0 4096
[ 2] .rodata PROGBITS 0000000000101000 002000 0000d8 00 AM 0 0 4096
[ 3] .data PROGBITS 0000000000102000 003000 00006e 00 WA 0 0 4096
[ 4] .bss NOBITS 0000000000103000 00306e 0040c0 00 WA 0 0 4096
[ 5] .debug_loc PROGBITS 0000000000000000 00306e 000143 00 0 0 1
[ 6] .debug_abbrev PROGBITS 0000000000000000 0031b1 00016b 00 0 0 1
[ 7] .debug_info PROGBITS 0000000000000000 00331c 000bd0 00 0 0 1
[ 8] .debug_ranges PROGBITS 0000000000000000 003eec 000070 00 0 0 1
[ 9] .debug_str PROGBITS 0000000000000000 003f5c 000d10 01 MS 0 0 1
[10] .debug_pubnames PROGBITS 0000000000000000 004c6c 00036c 00 0 0 1
[11] .debug_pubtypes PROGBITS 0000000000000000 004fd8 000359 00 0 0 1
[12] .debug_frame PROGBITS 0000000000000000 005338 0001a8 00 0 0 8
[13] .debug_line PROGBITS 0000000000000000 0054e0 000380 00 0 0 1
[14] .comment PROGBITS 0000000000000000 005860 000013 01 MS 0 0 1
[15] .symtab SYMTAB 0000000000000000 005878 000390 18 17 30 8
[16] .shstrtab STRTAB 0000000000000000 005c08 0000b4 00 0 0 1
[17] .strtab STRTAB 0000000000000000 005cbc 00025a 00 0 0 1
Key to Flags:
W (write), A (alloc), X (execute), M (merge), S (strings), I (info),
L (link order), O (extra OS processing required), G (group), T (TLS),
C (compressed), x (unknown), o (OS specific), E (exclude),
R (retain), l (large), p (processor specific)
Elf file type is EXEC (Executable file)
Entry point 0x0
There are 4 program headers, starting at offset 64
Program Headers:
Type Offset VirtAddr PhysAddr FileSiz MemSiz Flg Align
LOAD 0x001000 0x0000000000100000 0x0000000000100000 0x0006a6 0x0006a6 R E 0x1000
LOAD 0x002000 0x0000000000101000 0x0000000000101000 0x0000d8 0x0000d8 R 0x1000
LOAD 0x003000 0x0000000000102000 0x0000000000102000 0x00006e 0x0050c0 RW 0x1000
GNU_STACK 0x000000 0x0000000000000000 0x0000000000000000 0x000000 0x1000000 RW 0x0
Section to Segment mapping:
Segment Sections...
00 .text
01 .rodata
02 .data .bss
03 .bss
None .debug_loc .debug_abbrev .debug_info .debug_ranges .debug_str .debug_pubnames .debug_pubtypes .debug_frame .debug_line .comment .symtab .shstrtab .strtab
My build.zig and kernel.ld can be found on codeberg.
Now, what could be the cause of this problem? Or could it be a ZIG internal and should I report it on GitHub?
Looking forwards,
Samuel Fiedler
me…