Sean Christopherson 0e0ab73c9a KVM: VMX: Zero out *all* general purpose registers after VM-Exit ... ...except RSP, which is restored by hardware as part of VM-Exit. Paolo theorized that restoring registers from the stack after a VM-Exit in lieu of zeroing them could lead to speculative execution with the guest's values, e.g. if the stack accesses miss the L1 cache[1]. Zeroing XORs are dirt cheap, so just be ultra-paranoid. Note that the scratch register (currently RCX) used to save/restore the guest state is also zeroed as its host-defined value is loaded via the stack, just with a MOV instead of a POP. [1] https://patchwork.kernel.org/patch/10771539/#22441255 Fixes: 0cb5b30698 ("kvm: vmx: Scrub hardware GPRs at VM-exit") Cc: <stable@vger.kernel.org> Cc: Jim Mattson <jmattson@google.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>		2019-02-12 13:12:14 +01:00
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capabilities.h
evmcs.c	x86/kvm/hyper-v: nested_enable_evmcs() sets vmcs_version incorrectly	2019-01-25 19:11:37 +01:00
evmcs.h
nested.c	KVM: nVMX: Check a single byte for VMCS "launched" in nested early checks	2019-02-12 13:12:13 +01:00
nested.h
ops.h
pmu_intel.c
vmcs12.c
vmcs12.h
vmcs_shadow_fields.h
vmcs.h
vmenter.S
vmx.c	KVM: VMX: Zero out *all* general purpose registers after VM-Exit	2019-02-12 13:12:14 +01:00
vmx.h