• Wanpeng Li's avatar
    KVM: X86: Fix loss of exception which has not yet been injected · 664f8e26
    Wanpeng Li authored
    vmx_complete_interrupts() assumes that the exception is always injected,
    so it can be dropped by kvm_clear_exception_queue().  However,
    an exception cannot be injected immediately if it is: 1) originally
    destined to a nested guest; 2) trapped to cause a vmexit; 3) happening
    right after VMLAUNCH/VMRESUME, i.e. when nested_run_pending is true.
    
    This patch applies to exceptions the same algorithm that is used for
    NMIs, replacing exception.reinject with "exception.injected" (equivalent
    to nmi_injected).
    
    exception.pending now represents an exception that is queued and whose
    side effects (e.g., update RFLAGS.RF or DR7) have not been applied yet.
    If exception.pending is true, the exception might result in a nested
    vmexit instead, too (in which case the side effects must not be applied).
    
    exception.injected instead represents an exception that is going to be
    injected into the guest at the next vmentry.
    Reported-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
    Cc: Paolo Bonzini <pbonzini@redhat.com>
    Cc: Radim Krčmář <rkrcmar@redhat.com>
    Signed-off-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
    Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
    664f8e26
x86.c 225 KB