On 20/09/20 18:16, Sean Christopherson wrote: >> Maxim, your previous version was adding some error handling to >> kvm_x86_ops.set_efer. I don't remember what was the issue; did you have >> any problems propagating all the errors up to KVM_SET_SREGS (easy), >> kvm_set_msr (harder) etc.? > I objected to letting .set_efer() return a fault. So did I, and that's why we get KVM_REQ_OUT_OF_MEMORY. But it was more of an "it's ugly and it ought not to fail" thing than something I could pinpoint. It looks like we agree, but still we have to choose the lesser evil? Paolo > A relatively minor issue is > the code in vmx_set_efer() that handles lack of EFER because technically KVM > can emulate EFER.SCE+SYSCALL without supporting EFER in hardware. Returning > success/'0' would avoid that particular issue. My primary concern is that I'd > prefer not to add another case where KVM can potentially ignore a fault > indicated by a helper, a la vmx_set_cr4().
