On Wed, 17 Apr 2019 22:47:34 +1000 David Gibson <da...@gibson.dropbear.id.au> wrote:
> On Wed, Apr 17, 2019 at 02:01:29PM +0200, Greg Kurz wrote: > > On Wed, 17 Apr 2019 21:20:00 +1000 > > Nicholas Piggin <npig...@gmail.com> wrote: > > > [...] > > > >> @@ -1860,6 +1928,9 @@ static void hypercall_register_types(void) > > > >> /* hcall-splpar */ > > > >> spapr_register_hypercall(H_REGISTER_VPA, h_register_vpa); > > > >> spapr_register_hypercall(H_CEDE, h_cede); > > > >> + spapr_register_hypercall(H_CONFER, h_confer); > > > >> + spapr_register_hypercall(H_PROD, h_prod); > > > >> + > > > >> spapr_register_hypercall(H_SIGNAL_SYS_RESET, h_signal_sys_reset); > > > >> > > > > > > > > You're no longer enabling the KVM CONFER and PROD hypercalls. Are > > > > they enabled by default, or is that an intentional change? > > > > > > > AFAICT they seem to be enabled by default in HV KVM. > > > > > Oh, it was not intentional, I must not understand how this works. Why > > > is this no longer enabling the those hcalls? > > > > > > > Since linux commit 699a0ea0823d ("KVM: PPC: Book3S: Controls for in-kernel > > sPAPR hypercall handling"), in-kernel hypercalls are disabled by default > > and must be explicitely enabled by userspace. QEMU does that for some > > hypercalls already (search kvmppc_enable_set_mode_hcall() in QEMU for an > > example). > > > > Since H_CONFER and H_PROD are listed in default_hcall_list[] in book3s_hv.c, > > no need for QEMU to enable them in KVM. > > Ah, ok. Oops, that means the guest environment has been visibly > different for KVM and TCG all this time, which isn't great. > > > Not sure about David's "no longer" wording though. > > > "no longer" meaning the previous patch version had some > kvmppc_enable_hcall(), but this version doesn't. > Neither do the two previous versions of this patch actually, hence my questioning... No big deal :)
pgp2m9KKZJ8Tv.pgp
Description: OpenPGP digital signature