Memory versioning implementation (do not merge) #143
+662
−25
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
Contributor
Author
|
Notes from the commit message: This is an initial implementation and is an incomplete and slow notably:
|
It is incomplete and may be slow / buggy notably: 1) version checks are performed during capability permissions checks, using the iotlb to cache a pointer to version memory, which is allocated alongside tag memory in cheri_tagmem.c. It uses one byte per version instead of a nibble like the ARM MTE so a bit space inefficient. 2) Loads and stores via DDC will throw an exception if DDC is versioned. 3) No system register. Note that this is the result of rebasing against upstream and simultaneously squashing the previous branch. There had been quite a lot of upstream changes with conflicts and some not very interesting history so it turned out to be easier that way.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
This PR is for discussion of qemu memory versioning implementation -- I do not necessarily expect it to be merged and certainly not in the current state.
The extensions are specified in a PRs to the architecture document and on
mem_versionsbranch of the sail model.