# Re: \[PATCH v28 00/32\] Control-flow Enforcement: Shadow Stack

- From: Yu, Yu-cheng \<hidden\>
- Date: 2021-07-23 17:28:54 
- List: linux-doc
- Page: https://ratatoskr.run/linux-doc/2021/07/1456179
- Thread: https://ratatoskr.run/linux-doc/2021/07/1455208/t.md

```text
On 7/22/2021 2:08 PM, Dave Hansen wrote:
> On 7/22/21 1:51 PM, Yu-cheng Yu wrote:
>> Linux distributions with CET are available now, and Intel processors with CET
>> are already on the market.  It would be nice if CET support can be accepted
>> into the kernel.
>>
>> Changes in v28:
>> - Rebase to Linus tree v5.14-rc2.
>> - Patch #1: Update Document to indicate no-user-shstk also disables IBT.
>> - Patch #23: Update shstk_setup() with wrmsrl_safe().  Update return value.
>> - Patch #25: Split out copy_thread() changes.  Add support for old clone().
>>    Add comments.
>> - Add comments for get_xsave_addr() (Patch #25, #26).
>
> Could you characterize where this whole thing is?
>
> Are we at the point where the feedback is slowing down?  What kind of
> feedback are you getting?  How stable is the ABI versus the last revision?
>

The ABI has not changed since last version, except the addition of shadow stack support for legacy clone().  This does not de-stabilize the ABI.

Looking back at recent feedback:

- Boris had given lots of comments on code flow, syntax, etc.  Those are all addressed.

- Andy L. commented on the signal handling part, especially the introduction of a ucontext extension.  That is eliminated and now there is the UC_WAIT_ENDBR flag.

- Kirill commented a few issues on mm patches.  Those are addressed.

- Peter Z. requested splitting shadow stack and ibt.  That is done.

As for running/testing of the series, overall it is stable.

Yu-cheng
```