On Wed, Oct 09, 2019 at 10:58:35PM +0200, Paolo Bonzini wrote:
On 09/10/19 19:05, Sasha Levin wrote:
From: Jim Mattson jmattson@google.com
[ Upstream commit 43561123ab3759eb6ff47693aec1a307af0aef83 ]
For these CPUID leaves, the EDX output is not dependent on the ECX input (i.e. the SIGNIFCANT_INDEX flag doesn't apply to EDX). Furthermore, the low byte of the ECX output is always identical to the low byte of the ECX input. KVM does not produce the correct ECX and EDX outputs for any undefined subleaves beyond the first.
Special-case these CPUID leaves in kvm_cpuid, so that the ECX and EDX outputs are properly generated for all undefined subleaves.
Fixes: 0771671749b59a ("KVM: Enhance guest cpuid management") Fixes: a87f2d3a6eadab ("KVM: x86: Add Intel CPUID.1F cpuid emulation support") Signed-off-by: Jim Mattson jmattson@google.com Reviewed-by: Marc Orr marcorr@google.com Reviewed-by: Peter Shier pshier@google.com Reviewed-by: Jacob Xu jacobhxu@google.com Cc: Sean Christopherson sean.j.christopherson@intel.com Cc: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org
arch/x86/kvm/cpuid.c | 83 +++++++++++++++++++++++++------------------- 1 file changed, 47 insertions(+), 36 deletions(-)
This is absolutely not stable material. Is it possible for KVM to opt out of this AUTOSEL nonsense?
Sure, I've opted out KVM and removed all KVM patches from this series:
c1fac4516a61d kvm: vmx: Limit guest PMCs to those supported on the host 75b118586ec81 kvm: x86, powerpc: do not allow clearing largepages debugfs entry 06cd1710feaed KVM: VMX: Set VMENTER_L1D_FLUSH_NOT_REQUIRED if !X86_BUG_L1TF c89fc5c082aa6 KVM: x86: Expose XSAVEERPTR to the guest 1eec6b4068e2e kvm: x86: Use AMD CPUID semantics for AMD vCPUs 5c56e6ba0afc8 kvm: x86: Improve emulation of CPUID leaves 0BH and 1FH 94a3c6f010bd2 kvm: x86: Fix a spurious -E2BIG in __do_cpuid_func 79a7ad6330bc5 KVM: arm/arm64: vgic: Use the appropriate TRACE_INCLUDE_PATH
-- Thanks, Sasha