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X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Ard Biesheuvel , MSM , linux-arm-kernel , "Suzuki K. Poulose" , Catalin Marinas , Linux ARM Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2019-10-11 16:39, Marc Gonzalez wrote: > 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 > I think, it was fixed by commit: 5717fe5ab38f ("arm64: cpufeature: Don't treat granule sizes as strict") Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel