H. Peter Anvin wrote: > > This code is almost entirely identical to the setgpr_wrapper in the > patch (except for the fact that setgpr_wrapper sets and captures *ALL* > the GPRs), and it seems rather pointless to use another wrapper. It > takes a pointer to an entrypoint (default to "cpuid; ret" in the CPUID > case), so it should do what you need.
void (*cpuid)(unsigned int *eax, unsigned int *ebx, ...) Not quite. The paravirt_ops CPUID function is a C function which takes pointers to each GPR as arguments, and returns the values through those pointers. This doesn't allow for an entrypoint compatible with setgpr_wrapper, which expects the same output in both the cpuid; ret case and the paravirt-ops case. One could argue that the paravirt-ops CPUID should in fact emulate the native instruction semantics, which would make it a non-C function. However, until that bridge is crossed, we would need another wrapper after setgpr to convert the paravirt-ops CPUID back into the same format as native so that setgpr_wrapper can properly store the output fields into the common i386/x86_64 structure. What definitely should be done is hide this secondary wrapper in the paravirt-ops code so that your setgpr wrapper doesn't have to deal with weird issues like this because of paravirt-ops changes. Zach _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linux-foundation.org/mailman/listinfo/virtualization
