Messages in this thread | | | From | Ard Biesheuvel <> | Date | Thu, 7 Nov 2019 11:51:38 +0100 | Subject | Re: [PATCH v5 11/14] arm64: efi: restore x18 if it was corrupted |
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On Wed, 6 Nov 2019 at 05:46, Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> wrote: > > 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? >
Agreed, but only if you have to respin for other reasons.
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