General protection fault after reloading CS

[LolzDEV]

I'm following the GDT guide but according to gdb

Code: Select all

jmp 0x08:reload_cs

is causing a "General Protection Fault" (0xd), according to the wiki this exception is thrown when a code segment is used improperly but as far as I understand if the GDT is not set segmentation is not enabled. What's going on? I cannot really understand
PS: I'm using GRUB2 as bootloader with Multiboot2 specification and I'm in protected mode

[Octocontrabass]

as far as I understand if the GDT is not set segmentation is not enabled.

Segmentation is always enabled.

What's going on?

The CPU is unable to use the segment descriptor corresponding to segment selector 8 as a code segment.

• Maybe the selector is wrong, and your code segment needs a different selector.
• Maybe you've made a mistake defining the descriptor and it's not a valid code segment.
• Maybe you've made a mistake loading the GDTR and the CPU isn't reading your GDT.

It's hard to say for sure without more information. For example, post a link to your git repository, or provide a register dump using QEMU's "-d int" option.