signed arena load #8922
Closed
signed arena load #8922
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
kernel-patches-daemon-bpf
bot
force-pushed
the
bpf-next_base
branch
8 times, most recently
from
e692eda to
aaf75a5
Compare
kernel-patches-daemon-bpf
bot
force-pushed
the
bpf-next_base
branch
2 times, most recently
from
c9568f6 to
5ad6ff6
Compare
Currently, signed load instructions into arena memory are unsupported. The compiler is free to generate these, and on GCC-14 we see a corresponding error when it happens. The hurdle in supporting them is deciding which unused opcode to use to mark them for the JIT's own consumption. After much thinking, it appears 0xc0 / BPF_NOSPEC can be combined with load instructions to identify signed arena loads. Use this to recognize and JIT them appropriately, and remove the verifier side limitation on the program if the JIT supports them. Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]>
kernel-patches-daemon-bpf
bot
force-pushed
the
bpf-next_base
branch
9 times, most recently
from
49174bd to
f3a4188
Compare
|
Automatically cleaning up stale PR; feel free to reopen if needed |
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Outdated suggestions cannot be applied.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.
No description provided.