On Tue, Nov 01, 2022, Vitaly Kuznetsov wrote: > vmmcall()/vmcall() are used to exit from L2 to L1 and no concrete hypercall > ABI is currenty followed. With the introduction of Hyper-V L2 TLB flush > it becomes (theoretically) possible that L0 will take responsibility for > handling the call and no L1 exit will happen. Prevent this by stuffing RAX > (KVM ABI) and RCX (Hyper-V ABI) with 'safe' values. > > While on it, convert vmmcall() to 'static inline', make it setup stack > frame and move to include/x86_64/svm_util.h. > > Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> > --- Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>