[PATCH v3 0/2] arm64: Support systems without FP/ASIMD

Suzuki K Poulose suzuki.poulose at arm.com
Tue Nov 8 05:56:19 PST 2016


This series adds supports to the kernel and KVM hyp to handle
systems without FP/ASIMD properly. At the moment the kernel
doesn't check if the FP unit is available before accessing
the registers (e.g during context switch). Also for KVM,
we trap the FP/ASIMD accesses and handle it by injecting an
undefined instruction into the VM on systems without FP.

Tested on a FVP_Base-AEM-v8A model by disabling VFP on at
least one CPU ( -C clusterX.cpuY.vfp-present=0 ).

Changes since V2:
 - Dropped cleanup patch for arm64/crypto/aes-ce-ccm-glue.c
 - Removed static_key check from cpus_have_cap. All users with
   constant caps should use the new API to make use of static_keys.
 - Removed a dedicated static_key used in irqchip-gic-v3.c for
   Cavium errata with the new API.

Applies on v4.9-rc4 + [1] (which is pushed for rc5)

[1] http://marc.info/?l=linux-arm-kernel&m=147819889813214&w=2


Suzuki K Poulose (2):
  arm64: Add hypervisor safe helper for checking constant capabilities
  arm64: Support systems without FP/ASIMD

 arch/arm64/include/asm/cpucaps.h    |  3 ++-
 arch/arm64/include/asm/cpufeature.h | 24 +++++++++++++++++-------
 arch/arm64/include/asm/neon.h       |  3 ++-
 arch/arm64/kernel/cpufeature.c      | 17 ++++++++++++++++-
 arch/arm64/kernel/fpsimd.c          | 14 ++++++++++++++
 arch/arm64/kernel/process.c         |  2 +-
 arch/arm64/kvm/handle_exit.c        | 11 +++++++++++
 arch/arm64/kvm/hyp/hyp-entry.S      |  9 ++++++++-
 arch/arm64/kvm/hyp/switch.c         |  5 ++++-
 drivers/irqchip/irq-gic-v3.c        | 13 +------------
 10 files changed, 76 insertions(+), 25 deletions(-)

-- 
2.7.4




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