On Tue, Jul 07, 2026, Jim Mattson wrote: > On Tue, Jul 7, 2026 at 7:41 AM Sean Christopherson <[email protected]> wrote: > > > > insn = ctxt->fetch.data; > > if (ctxt->eip == kvm_rip_read(vcpu)) > > insn_len = ctxt->fetch.end - ctxt->fetch.ptr; > > > > for (len = X86_MAX_INSTRUCTION_LENGTH - insn_len; len >= 0; len--) { > > if (!kvm_fetch_guest_virt(vcpu, kvm_rip_read(vcpu) + > > insn_len, > > &insn[insn_len], len, NULL)) > > break; > > } > > This split doesn't bother you?
What split? Do you mean reading some bytes from the emulator, and some at the time of #VMEXIT? If so: no. IMO, the most important thing in practice is to capture the actual bytes used to decode the instruction that led to the #NPF. Exactly how and when the "CPU" reads the bytes is a micro-architectural detail, so I don't have any qualms from an architectural-correctness perspective.
