KVM/arm64: VM configuration enforcement

This is the fourth version of this configurationm enforcement series after additional reviewing from Suzuki and Oliver. Many thanks to both.

I think I have taken most of the feedback into account, but please shout if I have ignored something.

* From v3: [3]

- Fixed copy-paste issue while testing for the PAC flags

- Added Suzuki's RB on patch #2

* From v2: [2]

- Fix totally broken handling of negative features by delegating the work that requires a functionnal brain to other people

- Fix handling of HCR_ENSCXT as RES0 instead of RES1 (and its consequences...)

- Add handling of VTTBR_EL2.CNP being RES0

- Add a snapshot of all RES0/RES1 fields so that we can catch them being changed behind our backs

- Various cleanups

* From v1: [1]

- Fix embarrassing crash with FEAT_MOPS

- Better error handling in the FGT code

- Added/Fixed comments

- Simplified the __vcpu_sys_reg() macro

- Fixed FEAT_PIR handling

- Folded in Oliver's PMU rework

[1] https://lore.kernel.org/all/[email protected]
[2] https://lore.kernel.org/all/[email protected]
[3] https://lore.kernel.org/all/[email protected]

Marc Zyngier (26):
arm64: sysreg: Add missing ID_AA64ISAR[13]_EL1 fields and variants
KVM: arm64: Add feature checking helpers
KVM: arm64: nv: Add sanitising to VNCR-backed sysregs
KVM: arm64: nv: Add sanitising to EL2 configuration registers
KVM: arm64: nv: Add sanitising to VNCR-backed FGT sysregs
KVM: arm64: nv: Add sanitising to VNCR-backed HCRX_EL2
KVM: arm64: nv: Drop sanitised_sys_reg() helper
KVM: arm64: Unify HDFG[WR]TR_GROUP FGT identifiers
KVM: arm64: nv: Correctly handle negative polarity FGTs
KVM: arm64: nv: Turn encoding ranges into discrete XArray stores
KVM: arm64: Drop the requirement for XARRAY_MULTI
KVM: arm64: nv: Move system instructions to their own sys_reg_desc
array
KVM: arm64: Always populate the trap configuration xarray
KVM: arm64: Register AArch64 system register entries with the sysreg
xarray
KVM: arm64: Use the xarray as the primary sysreg/sysinsn walker
KVM: arm64: Rename __check_nv_sr_forward() to triage_sysreg_trap()
KVM: arm64: Add Fine-Grained UNDEF tracking information
KVM: arm64: Propagate and handle Fine-Grained UNDEF bits
KVM: arm64: Move existing feature disabling over to FGU infrastructure
KVM: arm64: Streamline save/restore of HFG[RW]TR_EL2
KVM: arm64: Make TLBI OS/Range UNDEF if not advertised to the guest
KVM: arm64: Make PIR{,E0}_EL1 UNDEF if S1PIE is not advertised to the
guest
KVM: arm64: Make AMU sysreg UNDEF if FEAT_AMU is not advertised to the
guest
KVM: arm64: Make FEAT_MOPS UNDEF if not advertised to the guest
KVM: arm64: Snapshot all non-zero RES0/RES1 sysreg fields for later
checking
KVM: arm64: Add debugfs file for guest's ID registers

 arch/arm64/include/asm/kvm_arm.h           |   4 +-
 arch/arm64/include/asm/kvm_host.h          |  98 +++++++-
 arch/arm64/include/asm/kvm_nested.h        |   1 -
 arch/arm64/kvm/Kconfig                     |   1 -
 arch/arm64/kvm/arm.c                       |   7 +
 arch/arm64/kvm/check-res-bits.h            | 121 ++++++++++
 arch/arm64/kvm/emulate-nested.c            | 231 +++++++++++++-----
 arch/arm64/kvm/hyp/include/hyp/switch.h    | 130 +++++-----
 arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h |  24 +-
 arch/arm64/kvm/nested.c                    | 267 ++++++++++++++++++++-
 arch/arm64/kvm/pmu-emul.c                  |  11 +-
 arch/arm64/kvm/sys_regs.c                  | 238 +++++++++++++++---
 arch/arm64/kvm/sys_regs.h                  |   2 +
 arch/arm64/tools/sysreg                    |   8 +-
 include/kvm/arm_pmu.h                      |  11 -
 15 files changed, 973 insertions(+), 181 deletions(-)
 create mode 100644 arch/arm64/kvm/check-res-bits.h

2.39.2