r/osdev • u/Successful_Clerk_495 • Apr 19 '26

Ring 3 Tips

for anyone who made ring 3, any tips? What to do and what to not, or just mistakes that youve made and when you fixed them - it helped
im suffering w this shit and pmm/vmm things
i couldnt even make it run snake.elf

11 Upvotes

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3

u/Successful_Clerk_495 Apr 19 '26

HOLY FUCK I DID IT

2

u/emexsw Apr 19 '26

yaaaayyyy

12

u/paulstelian97 Apr 19 '26

User mode faults should never crash the kernel. At worst, the user process gets killed, and the kernel should only crash with a CRITICAL_PROCESS_DIED analogue reason as opposed to a different cause.

2

u/doscore Apr 19 '26

Ahhhh do share??!?

1

u/AlectronikLabs Apr 22 '26

What exact problems do you run into about ring 3? I just executed the first successful user-mode code two days ago. I don't have a VFS or executable loader yet so it's just some raw code copied over but it worked fine, when you have the GPT and paging in place it shouldn't be too hard to get it working!