Re: [PATCH 0/7] arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9

From: Rob Herring
Date: Thu Jan 02 2025 - 11:04:11 EST


On Fri, Dec 20, 2024 at 12:52:33PM +0530, Anshuman Khandual wrote:
> This series adds fine grained trap control in EL2 required for FEAT_PMUv3p9
> registers like PMICNTR_EL0, PMICFILTR_EL0, and PMUACR_EL1 which are already
> being used in the kernel. This is required to prevent their EL1 access trap
> into EL2.
>
> PMZR_EL0 register trap control i.e HDFGWTR2_EL2.nPMZR_EL0 remains unchanged
> for now as it does not get accessed in the kernel, and there is no plan for
> its access from user space.
>
> I have taken the liberty to pick up all the review tags for patches related
> to tools sysreg update from the KVM FGT2 V2 patch series posted earlier.
>
> https://lore.kernel.org/all/20241210055311.780688-1-anshuman.khandual@xxxxxxx/
>
> Rob had earler mentioned about FEAT_FGT2 based trap control requirement for
> FEAT_PMUv3p9 registers that are currently being used in kernel. The context
> can be found here.
>
> https://lore.kernel.org/all/20241216234251.GA629562-robh@xxxxxxxxxx/
>
> This series is based on v6.13-rc3
>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will@xxxxxxxxxx>
> Cc: Marc Zyngier <maz@xxxxxxxxxx>
> Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: Mark Brown <robh@xxxxxxxxxx>
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Cc: Oliver Upton <oliver.upton@xxxxxxxxx>
> Cc: Jonathan Corbet <corbet@xxxxxxx>
> Cc: Eric Auger <eric.auger@xxxxxxxxxx>
> Cc: kvmarm@xxxxxxxxxxxxxxx
> Cc: linux-doc@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
>
> Anshuman Khandual (7):
> arm64/sysreg: Update register fields for ID_AA64MMFR0_EL1
> arm64/sysreg: Add register fields for HDFGRTR2_EL2
> arm64/sysreg: Add register fields for HDFGWTR2_EL2
> arm64/sysreg: Add register fields for HFGITR2_EL2
> arm64/sysreg: Add register fields for HFGRTR2_EL2
> arm64/sysreg: Add register fields for HFGWTR2_EL2
> arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9

In case it is not clear, this series should be applied to 6.13 as the 2
PMUv3p9 features already landed in 6.13 (per counter EL0 control) and
6.12 (ICNTR).

Rob