Questions tagged [grub]
GENERAL GRUB SUPPORT IS OFF-TOPIC. Support questions may be asked on https://superuser.com. GRUB, the GNU GRand Unified Bootloader, is a boot loader used on x86 systems, typically used to boot Linux. Questions about using or configuring GRUB are rarely on-topic for Stack Overflow outside of unusual circumstances.
grub
174
questions
-2
votes
0
answers
16
views
Linux fedora option won't appear on grub boot menu after new fedora (additional) instalation [closed]
Recently I had my fedora (39) running ok, every time I booted the pc grub boot menu jumped in asking which distro I wanted to run. Everything ok.
Then I created a new disk partition and installed a ...
- 25
1
vote
0
answers
51
views
Using global variables after booting from GRUB before setting up the GDT
I'm writing a toy-kernel and the first step would be to set-up the GDT. Obviously I will be using variables on the stack to initialize the GDT; for which, a GDT must already be set up, which is indeed ...
- 5,134
0
votes
0
answers
21
views
"Encountered an issue where Windows 7 could not properly move the stage2 part to the specified location while writing the dual-boot bootloader
I am writing a bootloader for a dual-system (Win7, Ubuntu). After selecting Win7 in the selection interface, the system jumps to the breakpoint I set at 0x7c00. However, when I use 'layout asm' to ...
- 1
1
vote
0
answers
48
views
QEMU: address of grub module has zeros if not referenced directly in the code
The title sounds strange, but it's a real quantum physics style random bug I can't comprehend and get past.
I'm loading a non-empty tar archive as grub module, and grub gives me address of 0x14F000.
...
- 47
3
votes
0
answers
129
views
How can I pass VBE information to the kernel from the GRUB bootloader?
I need to somehow pass information to VBE, how do I do this?
Bootloader code:
#define ASM_FILE 1
#include <grub/multiboot.h>
#ifdef HAVE_ASM_USCORE
#define EXT_C(sym) ...
- 41
0
votes
0
answers
44
views
Grub script how to remove menuentries
I made a grub script to detect bootable disks and show them on grub menu. It is working but I want to put a rescan button and to make that first I need to remove old menuentries. How can I do?
My ...
- 316
1
vote
0
answers
56
views
I don't get correct information from GRUB multiboot2 | OS Development
I'm currently trying out grub by writing my own OS. The whole thing with the help of the docs and open source code. Since I'm having a bit of a hard time with the resources I find, I can't really make ...
- 59
1
vote
1
answer
334
views
GRUB not Switching to Graphics Mode in Custom OS Development
I am developing a custom operating system and using the GRUB bootloader to load my kernel. In my development process, I've encountered an issue where I am unable to switch the display mode from text ...
- 13
3
votes
1
answer
105
views
What is the grub/machine include directory in GRUB source code?
I have always wondered how does GRUB 2 work. While reading it's source code, I saw that there are some #include directives which include seemingly nonexistent "grub/machine/...", for example ...
- 47
2
votes
1
answer
272
views
Where in memory will os boot code be loaded when using grub chainloader?
Problem Description
Hi. I want to use grub chainloader to load my minios (an os I developed myself, not linux or windows).
Before using grub chainloader, minios boot process was BIOS->MBR->os ...
- 33
0
votes
2
answers
474
views
Modify a specific line in Ansible
How to update a line in /etc/default/grub using Ansible from ->
GRUB_CMDLINE_LINUX="audit=1 crashkernel=auto rhgb quiet"
to
GRUB_CMDLINE_LINUX="audit=1 crashkernel=auto rhgb quiet ...
- 11
0
votes
1
answer
189
views
CR0 contains PE/PG flags right upon the Linux Kernel startup
I'm using GNU GRUB version 2.04 bootloader and Linux Kernel 5.19-rc2
I'm debugging the Linux Kernel initialization and expected that right upon the Kernel startup the CPU should be in real mode. ...
- 9,347
-1
votes
2
answers
933
views
what is magic number to find whether OS on disk present and is it same for all archetectures & devices.Or is it bootloader 2 decide what it should be
I was trying to study bootloader and OS and bios do. So
I found this link
https://dev.to/frosnerd/writing-my-own-boot-loader-3mld
which lead to a lengthy tutorial from a university professor. from the ...
- 4,254
0
votes
1
answer
2k
views
mmap error : cannot allocate memory. how to allocate enough default sized huge pages as admin?
I was compiling and running this program but received 'mmap error : cannot allocate memory'.
The comment at the top reads
/*
* Example of using hugepage memory in a user application using the mmap
* ...
- 5,653
0
votes
1
answer
237
views
Why does grub-file say that NASM raw binary is not multiboot2 compliant?
I am trying to make a minimal kernel. My goal is to make this not-yet-existing kernel to be multiboot2 compliant. So I started out by creating a minimal multiboot2-header in NASM-Assembly.
I am using ...
