Re: [PATCH v5 11/14] arm64: efi: restore x18 if it was corrupted

Miguel Ojeda
2019-11-06T04:46:19Z

On Wed, Nov 6, 2019 at 12:56 AM Sami Tolvanen <samitolvanen@google.com> wrote:
>
> If we detect a corrupted x18 and SCS is enabled, restore the register
> before jumping back to instrumented code. This is safe, because the
> wrapper is called with preemption disabled and a separate shadow stack
> is used for interrupt handling.

In case you do v6: I think putting the explanation about why this is
safe in the existing comment would be best given it is justifying a
subtlety of the code rather than the change itself. Ard?

Cheers,
Miguel