Fix real mode transition #294
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
wipawel
previously approved these changes
Aug 29, 2023
minipli-oss
reviewed
Aug 29, 2023
minipli-oss
reviewed
Aug 29, 2023
Going into real mode would crash when clearing EFER_LME, i.e., when transitioning from long to protected mode. This happened because paging was still enabled. Before disabling paging, we must also set the %ds. Signed-off-by: Johannes Wikner <[email protected]>
Signed-off-by: Johannes Wikner <[email protected]>
In protected mode, like in head.S, we want to be able to save all
registers. {SAVE,RESTORE}_ALL_REGS32 should therefore always be working
on 32-bit registers and not be build-dependent.
Signed-off-by: Johannes Wikner <[email protected]>
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Going into real mode would crash on the wrmsr that clears the EFER_LME flag. This happened because paging was still enabled. And before disabling paging, we must also set the %ds.