[PATCH 0/2] KVM: arm64: Make AArch64 support sticky

[Marc Zyngier <maz@kernel.org>]

It's been recently reported[1] that our sorry excuse for a test suite
is writing a bunch of zeroes to ID_AA64PFR0_EL1.EL{0,1,2,3},
effectively removing the advertised support for AArch64 to the guest.

This leads to an interesting interaction with the NV code which reacts
in a slightly overzealous way and inject an UNDEF at the earliest
opportunity.

This small series fixes KVM by bluntly refusing to disable AArch64,
and the test to stop being so lame. I'm also fixing the NV code
separately, since it isn't upstream.

[1] https://lore.kernel.org/r/4e63a13f-c5dc-4f97-879a-26b5548da07f@os.amperecomputing.com

Marc Zyngier (2):
  KVM: arm64: Prevent userspace from disabling AArch64 support at any
    virtualisable EL
  KVM: arm64: selftest: Don't try to disable AArch64 support

 arch/arm64/kvm/sys_regs.c                       | 6 ++++++
 tools/testing/selftests/kvm/arm64/set_id_regs.c | 8 ++++----
 2 files changed, 10 insertions(+), 4 deletions(-)

-- 
2.39.2