On 11/10/2019 12:50, Mark Rutland wrote: > Before we make any changes, we need to check whether we do actually > handle this variation in a safe way, and we need to consider what this > means w.r.t. late CPU hotplug. > > Even if we can handle variation at boot time, once we've determined the > set of system-wide features we cannot allow those to regress, and I > believe we'll need new code to enforce that. I don't think it's > sufficient to mark these as NONSTRICT, though we might do that with > other changes. > > We shouldn't look at the part number at all here. We care about > variation across CPUs regardless of whether this is big.LITTLE or some > variation in tie-offs, etc. See also the "Unexpected variation in SYS_ID_AA64MMFR0_EL1" thread from a year ago: (that was on msm8998) https://www.spinics.net/lists/arm-kernel/msg691242.html Regards.
