[PATCH v6 0/7] KVM: arm64: Normalize cache configuration

Akihiko Odaki akihiko.odaki at daynix.com
Sat Jan 7 01:46:22 PST 2023


Before this change, the cache configuration of the physical CPU was
exposed to vcpus. This is problematic because the cache configuration a
vcpu sees varies when it migrates between vcpus with different cache
configurations.

Fabricate cache configuration from the sanitized value, which holds the
CTR_EL0 value the userspace sees regardless of which physical CPU it
resides on.

V5 -> V6:
- Add a comment to get_min_cache_line_size()

V4 -> V5:
- Noted why cache level existence check is unnecessary when fabricating
  CCSIDR_EL1 value.
- Removed FWB check. It is necessary as CLIDR_EL1.{LoUU, LoIUS} on the
  host are {0, 0} if FWB is enabled, and such a CLIDR_EL1 value sets
  the IDC bit of the sanitized CTR_EL0 value, which is already checked.
- Removed UNDEF injection when reading CCSIDR_EL1 with an invalid
  CSSELR_EL1 value.
- Added a check for CLIDR_EL1.{LoUU,LoC,LoUIS} values set from the
  userspace.

V3 -> V4:
- Implemented UNKNOWN system register definition for CCSIDR_EL1
- Added a comment about the relation between CCSIDR_EL1 and FEAT_CCIDX
- Squashed "Normalize cache configuration" and "Allow user to set
  CCSIDR_EL1"
  The intermediate state between them did not make much sense.
- Introduced FIELD_GET to extract CCSIDR_EL1_LineSize.

V2 -> V3:
- Corrected message for patch "Normalize cache configuration"
- Split patch "Normalize cache configuration"
- Added handling for CSSELR_EL1.TnD
- Added code to ignore RES0 in CSSELR_EL1
- Replaced arm64_ftr_reg_ctrel0.sys_val with
  read_sanitised_ftr_reg(SYS_CTR_EL0)
- Fixed vcpu->arch.ccsidr initialziation
- Added CCSIDR_EL1 sanitization
- Added FWB check
- Added a comment for CACHE_TYPE_SEPARATE
- Added MTE tag cache creation code for CLIDR_EL1 fabrication
- Removed CLIDR_EL1 reset code for reset caused by guest
- Added a comment for CCSIDR2

V2: https://lore.kernel.org/lkml/20221211051700.275761-2-akihiko.odaki@daynix.com/
V1: https://lore.kernel.org/lkml/525ff263-90b3-5b12-da31-171b09f9ad1b@daynix.com/

Akihiko Odaki (6):
  arm64/sysreg: Convert CCSIDR_EL1 to automatic generation
  arm64/sysreg: Add CCSIDR2_EL1
  arm64/cache: Move CLIDR macro definitions
  KVM: arm64: Always set HCR_TID2
  KVM: arm64: Mask FEAT_CCIDX
  KVM: arm64: Normalize cache configuration

Marc Zyngier (1):
  arm64: Allow the definition of UNKNOWN system register fields

 arch/arm64/include/asm/cache.h             |   9 +
 arch/arm64/include/asm/kvm_arm.h           |   3 +-
 arch/arm64/include/asm/kvm_emulate.h       |   4 -
 arch/arm64/include/asm/kvm_host.h          |   6 +-
 arch/arm64/include/asm/sysreg.h            |   1 -
 arch/arm64/kernel/cacheinfo.c              |   5 -
 arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h |   2 -
 arch/arm64/kvm/reset.c                     |   1 +
 arch/arm64/kvm/sys_regs.c                  | 263 +++++++++++++--------
 arch/arm64/tools/gen-sysreg.awk            |  20 +-
 arch/arm64/tools/sysreg                    |  17 ++
 11 files changed, 219 insertions(+), 112 deletions(-)

-- 
2.38.1




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