linux/arch/x86/kvm/vmx
Sean Christopherson 6ce347af14 KVM: nVMX: Preserve exception priority irrespective of exiting behavior
Short circuit vmx_check_nested_events() if an exception is pending and
needs to be injected into L2, priority between coincident events is not
dependent on exiting behavior.  This fixes a bug where a single-step #DB
that is not intercepted by L1 is incorrectly dropped due to servicing a
VMX Preemption Timer VM-Exit.

Injected exceptions also need to be blocked if nested VM-Enter is
pending or an exception was already injected, otherwise injecting the
exception could overwrite an existing event injection from L1.
Technically, this scenario should be impossible, i.e. KVM shouldn't
inject its own exception during nested VM-Enter.  This will be addressed
in a future patch.

Note, event priority between SMI, NMI and INTR is incorrect for L2, e.g.
SMI should take priority over VM-Exit on NMI/INTR, and NMI that is
injected into L2 should take priority over VM-Exit INTR.  This will also
be addressed in a future patch.

Fixes: b6b8a1451f ("KVM: nVMX: Rework interception of IRQs and NMIs")
Reported-by: Jim Mattson <jmattson@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Peter Shier <pshier@google.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200423022550.15113-2-sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-13 12:14:25 -04:00
..
capabilities.h KVM: x86: Handle PKU CPUID adjustment in VMX code 2020-03-16 17:58:19 +01:00
evmcs.c KVM: eVMCS: check if nesting is enabled 2020-04-23 09:04:56 -04:00
evmcs.h KVM: nVMX: properly handle errors in nested_vmx_handle_enlightened_vmptrld() 2020-03-16 18:19:30 +01:00
nested.c KVM: nVMX: Preserve exception priority irrespective of exiting behavior 2020-05-13 12:14:25 -04:00
nested.h KVM: x86: move nested-related kvm_x86_ops to a separate struct 2020-04-23 09:04:57 -04:00
ops.h KVM: VMX: Drop redundant capability checks in low level INVVPID helpers 2020-04-20 17:26:08 -04:00
pmu_intel.c KVM: VMX: Directly query Intel PT mode when refreshing PMUs 2020-03-16 17:58:38 +01:00
vmcs.h KVM: VMX: Leave preemption timer running when it's disabled 2019-06-18 17:10:46 +02:00
vmcs12.c KVM: nVMX: Remove non-functional "support" for CR3 target values 2020-04-21 09:13:09 -04:00
vmcs12.h KVM: nVMX: Remove non-functional "support" for CR3 target values 2020-04-21 09:13:09 -04:00
vmcs_shadow_fields.h KVM: Fix some out-dated function names in comment 2020-01-21 13:57:27 +01:00
vmenter.S KVM: VMX: Explicitly clear RFLAGS.CF and RFLAGS.ZF in VM-Exit RSB path 2020-05-06 06:51:35 -04:00
vmx.c Merge branch 'kvm-amd-fixes' into HEAD 2020-05-13 12:14:05 -04:00
vmx.h KVM: VMX: Cache vmcs.EXIT_INTR_INFO using arch avail_reg flags 2020-04-21 09:13:07 -04:00