line 32 is empty and I don't see anything egregiously wrong
#UEFI Heap allocation seems not to work anymore
royal cave
tall sun
ooops, forgot to push... 😅 . Now it's there.
royal cave
Ah, I see. uefi.pool_allocator is only allowed when boot services are enabled because it's implemented with boot_services.AllocatePool()
when you call exitBootServices you're leaving the environment where most of std.os.uefi is allowed
after you call exitBootServices you're intended to take the memory map and create your own allocator
tall sun
Ah, now I understand! Thank you very much!
open barn
yeah usually you take from UEFI what you want (files, GOP, RSDP, memory map, etc) and you get out. I prefer to use AllocatePages instead so it's aligned to 0x1000 and you can manage it really easy in your kernel afterwards
tall sun
Oh thank you, I'll try that.
tall sun
Now when I try to allocate a page (line 32 of https://codeberg.org/hi7/lunaos-zig/src/branch/main/src/main.zig):
var mem: [*]align(4096) u8 = undefined;
var status = boot_services.allocatePages(uefi.tables.AllocateType.AllocateAnyPages, uefi.tables.MemoryType.LoaderData, 1, &mem);
Status is not showing me what went wrong. QEMU shows me this, from which I can not infer the cause:
KVM internal error. Suberror: 1
extra data[0]: 0x0000000000000001
extra data[1]: 0x9090909090900001
extra data[2]: 0x9090909090909090
extra data[3]: 0x0000000000000400
extra data[4]: 0x0000000100000014
extra data[5]: 0x00000000000b0000
extra data[6]: 0x0000000000000000
extra data[7]: 0x0000000000000000
emulation failure
RAX=000000004743759e RBX=000000000629b1c8 RCX=0000000000000000 RDX=0000000000000002
RSI=0000000006958018 RDI=0000000006958018 RBP=0000000007f106f0 RSP=0000000007f10668
R8 =0000000000000001 R9 =0000000007f107c8 R10=0000000000000000 R11=0000000007f107d0
R12=0000000000000000 R13=0000000006e79be0 R14=0000000006e787bc R15=0000000006957f98
RIP=00000000000affff RFL=00000003 [------C] CPL=0 II=0 A20=1 SMM=0 HLT=0
ES =0030 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA]
CS =0038 0000000000000000 ffffffff 00a09b00 DPL=0 CS64 [-RA]
SS =0030 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA]
DS =0030 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA]
FS =0030 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA]
GS =0030 0000000000000000 ffffffff 00c09300 DPL=0 DS [-WA]
LDT=0000 0000000000000000 0000ffff 00008200 DPL=0 LDT
TR =0000 0000000000000000 0000ffff 00008b00 DPL=0 TSS64-busy
GDT= 00000000079de000 00000047
IDT= 0000000007471018 00000fff
CR0=80010033 CR2=0000000000000000 CR3=0000000007c01000 CR4=00000668
DR3=0000000000000000
DR6=00000000ffff0ff0 DR7=0000000000000400
EFER=0000000000000d00
Code=00 01 00 21 00 01 00 22 00 01 00 22 00 01 00 22 00 01 00 22 <00> ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
can you try without KVM?
or not faulting at all?
I suggest you start using serial 0xE9 to debug, it's more useful
tall sun
Ok, without KVM and serial to stdio I got:
BdsDxe: failed to load Boot0001 "UEFI QEMU DVD-ROM QM00003 " from PciRoot(0x0)/Pci(0x1,0x1)/Ata(Secondary,Master,0x0): Not Found
BdsDxe: loading Boot0002 "UEFI QEMU HARDDISK QM00001 " from PciRoot(0x0)/Pci(0x1,0x1)/Ata(Primary,Master,0x0)
BdsDxe: starting Boot0002 "UEFI QEMU HARDDISK QM00001 " from PciRoot(0x0)/Pci(0x1,0x1)/Ata(Primary,Master,0x0)
!!!! X64 Exception Type - 06(#UD - Invalid Opcode) CPU Apic ID - 00000000 !!!!
RIP - 00000000000B0001, CS - 0000000000000038, RFLAGS - 0000000000000803
RAX - 000000004743759E, RCX - 0000000000000000, RDX - 0000000000000002
RBX - 00000000062962C8, RSP - 0000000007F10668, RBP - 0000000007F106F0
RSI - 000000000695A018, RDI - 000000000695A018
R8 - 0000000000000001, R9 - 0000000007F107C8, R10 - 0000000000000000
R11 - 0000000007F107D0, R12 - 0000000000000000, R13 - 0000000006E79BE0
R14 - 0000000006E787BC, R15 - 0000000006957F98
DS - 0000000000000030, ES - 0000000000000030, FS - 0000000000000030
GS - 0000000000000030, SS - 0000000000000030
CR0 - 0000000080010033, CR2 - 0000000000000000, CR3 - 0000000007C01000
CR4 - 0000000000000668, CR8 - 0000000000000000
DR0 - 0000000000000000, DR1 - 0000000000000000, DR2 - 0000000000000000
DR3 - 0000000000000000, DR6 - 00000000FFFF0FF0, DR7 - 0000000000000400
GDTR - 00000000079DE000 0000000000000047, LDTR - 0000000000000000
IDTR - 0000000007471018 0000000000000FFF, TR - 0000000000000000
FXSAVE_STATE - 0000000007F102C0
!!!! Can't find image information. !!!!
Invalid Opcode is a little surprising...
open barn
are you using -dint?
-d int sorry
qemu-system-x86_64: -drive format=raw,file=fat:rw:esp: Could not read directory esp
I am trying to run the project but this error pops @tall sun
is there any way to get the whole running workflow automatized?
tall sun
Oh esp/efi/boot folders are not in the repository. If your create them with mkdir and make a symbolic link (see README) it
should work.
I run it with zig build run
I've pushed the QEMU parameter updates.
When I run it with -d int I got a lot of output... but the last is still Invalid Opcode
open barn
yeah
you have to check for the first check_exception
I'd suggest using 0xE9 for debugging
it's way more comfortable than drawing to the screen
you can't use gdb yet because the UEFI executable is PE, unless you like debugging asm
instead of -serial stdio, you have to use -debugcon stdio
then write a writer
const bytes_left = asm volatile (
\\rep outsb
: [ret] "={rcx}" (-> usize),
: [dest] "{dx}" (port),
[src] "{rsi}" (bytes.ptr),
[len] "{rcx}" (bytes.len),
: "rsi", "rcx"
);
return bytes.len - bytes_left;
}
pub const E9Writer = std.io.Writer(void, E9WriterError, writeToE9);
pub const writer = E9Writer{ .context = {} };
fn writeToE9(_: void, bytes: []const u8) E9WriterError!usize {
return arch.io.writeBytes(0xe9, bytes);
}
and you can use writer.print like if it were std.io.getStdout().writer().print
way easier 🙂
arch.io.writeBytes is the writeBytes function I pasted earlier
-debugcon stdio is a magic thing which will tell qemu to write to stdio every byte you send to the 0xe9 port
tall sun
Cool I try that! Thank you so much!