Excerpts from Nicholas Piggin's message of March 6, 2021 1:06 am: > This sets up the same calling convention from interrupt entry to > KVM interrupt handler for system calls as exists for other interrupt > types. > > This is a better API, it uses a save area rather than SPR, and it has > more registers free to use. Using a single common API helps maintain > it, and it becomes easier to use in C in a later patch. On second look I'm happy enough with this. It does add some hcall setup code back into exception-64s.S and removes most of the "fixup" code that was previously moved into book3s_64_entry.S in patch 12. But if you take patch 12 and 13 and other earlier patches together they are moving most KVM interrupt knowledge into KVM which is a good change. Once that is done, this final one then gets hcall into better shape for the C code. If anything this patch could go together with patch 12 but I guess I ended up writing it for the C code whereas the previous ones were cleanups so the ordering didn't come out that way. It won't be trivial to move now so I don't think I'd bother. Thanks, Nick
