[PATCH 0/2] KVM: arm64: Uphold 64bit-only behavior on asymmetric systems

Oliver Upton oliver.upton at linux.dev
Thu Aug 11 10:02:19 PDT 2022


Small series to fix a couple issues around when 64bit-only behavior is
applied. As KVM is more restrictive than the kernel in terms of 32bit
support (no asymmetry), we really needed our own predicate when the
meaning of system_supports_32bit_el0() changed in commit 2122a833316f
("arm64: Allow mismatched 32-bit EL0 support").

Lightly tested as I do not have any asymmetric systems on hand at the
moment. Attention on patch 2 would be appreciated as it affects ABI.

Oliver Upton (2):
  KVM: arm64: Treat PMCR_EL1.LC as RES1 on asymmetric systems
  KVM: arm64: Reject 32bit user PSTATE on asymmetric systems

 arch/arm64/include/asm/kvm_host.h | 4 ++++
 arch/arm64/kvm/arm.c              | 3 +--
 arch/arm64/kvm/guest.c            | 2 +-
 arch/arm64/kvm/sys_regs.c         | 4 ++--
 4 files changed, 8 insertions(+), 5 deletions(-)


base-commit: 21f9c8a13bb2a0c24d9c6b86bc0896542a28c197
-- 
2.37.1.559.g78731f0fdb-goog




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