On Thu, 6 May 2021 14:49:58 +1000, Michael Ellerman wrote:
> The STF (store-to-load forwarding) barrier mitigation can be
> enabled/disabled at runtime via a debugfs file (stf_barrier), which
> causes the kernel to patch itself to enable/disable the relevant
> mitigations.
>
> However depending on which mitigation we're using, it may not be safe to
> do that patching while other CPUs are active. For example the following
> crash:
>
> [...]
Applied to powerpc/fixes.
[1/2] powerpc/64s: Fix crashes when toggling stf barrier
https://git.kernel.org/powerpc/c/8ec7791bae1327b1c279c5cd6e929c3b12daaf0a
[2/2] powerpc/64s: Fix crashes when toggling entry flush barrier
https://git.kernel.org/powerpc/c/aec86b052df6541cc97c5fca44e5934cbea4963b
cheers
