On Tue, 4 May 2021 at 09:16, Nicholas Piggin <npig...@gmail.com> wrote: > > Excerpts from Joel Stanley's message of May 4, 2021 10:51 am: > > On Mon, 3 May 2021 at 13:04, Nicholas Piggin <npig...@gmail.com> wrote: > >> > >> These aren't necessarily POWER9 only, and it's not to say some new > >> vulnerability may not get discovered on other processors for which > >> we would like the flexibility of having the workaround enabled by > >> firmware. > >> > >> Remove the restriction that they only apply to POWER9. > > > > I was wondering how these worked which led me to reviewing your patch. > > From what I could see, these are enabled by default (SEC_FTR_DEFAULT > > in arch/powerpc/include/asm/security_features.h), so unless all > > non-POWER9 machines have set the "please don't" bit in their firmware > > this patch will enable the feature for those machines. Is that what > > you wanted? > > Yes. POWER7/8 should be affected (it's similar mechanism that requires > the meltdown RFI flush, which those processors need). > > POWER10 we haven't released a bare metal firmware with the right bits > yet. Not urgent at the moment but wouldn't hurt to specify them and > add the Linux code for them.
Thanks for the explanation. This could go in the commit message if you re-spin. Reviewed-by: Joel Stanley <j...@jms.id.au>
