On Wed, Apr 25, 2018 at 11:52:18AM +0200, Cédric Le Goater wrote: > On 04/17/2018 09:17 AM, David Gibson wrote: > > In cpu_ppc_set_papr() the UPRT and GTSE bits of the LPCR are initialized > > based on on ppc64_radix_guest(). Which seems reasonable, except that > > ppc64_radix_guest() is based on spapr->patb_entry which is only set up > > in spapr_machine_reset, called much later than cpu_ppc_set_papr(). > > > > So the initialization here is pointless. The base cpu initialization > > already sets a value that's good enough until the guest uses an hcall to > > configure it's preferred MMU mode. > > > > Signed-off-by: David Gibson <da...@gibson.dropbear.id.au> > > --- > > target/ppc/translate_init.c | 16 ---------------- > > 1 file changed, 16 deletions(-) > > > > diff --git a/target/ppc/translate_init.c b/target/ppc/translate_init.c > > index bb79d23b50..14f346f441 100644 > > --- a/target/ppc/translate_init.c > > +++ b/target/ppc/translate_init.c > > @@ -8897,22 +8897,6 @@ void cpu_ppc_set_papr(PowerPCCPU *cpu, > > PPCVirtualHypervisor *vhyp) > > lpcr->default_value &= ~LPCR_RMLS; > > lpcr->default_value |= 1ull << LPCR_RMLS_SHIFT; > > > > - if (env->mmu_model == POWERPC_MMU_3_00) { > > - /* By default we choose legacy mode and switch to new hash or radix > > - * when a register process table hcall is made. So disable process > > - * tables and guest translation shootdown by default > > - * > > - * Hot-plugged CPUs inherit from the guest radix setting under > > - * KVM but not under TCG. Update the default LPCR to keep new > > - * CPUs in sync when radix is enabled. > > - */ > > > This is breaking CPU hotplug under TCG. Should we reintroduce the same > settings in spapr_cpu_reset() now ?
Sod. Yeah, this code is important for the hotplug case. But, no, I don't think it should go into reset, I think it should go into the rtas start-cpu path; it only makes sense for secondary CPUs. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson
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