Commit 0550b120 authored by Greg Kurz's avatar Greg Kurz Committed by David Gibson
Browse files

spapr: don't advertise radix GTSE if max-compat-cpu < power9 



On a POWER9 host, if a guest runs in pre POWER9 compat mode, it necessarily
uses the hash MMU mode. In this case, we shouldn't advertise radix GTSE in
the ibm,arch-vec-5-platform-support DT property as the current code does.
The first reason is that it doesn't make sense, and the second one is that
causes the CAS-negotiated options subsection to be migrated. This breaks
backward migration to QEMU 2.7 and older versions on POWER8 hosts:

qemu-system-ppc64: error while loading state for instance 0x0 of device
 'spapr'
qemu-system-ppc64: load of migration failed: No such file or directory

This patch hence initialize CPUs a bit earlier so that we can check the
requested compat mode, and don't set OV5_MMU_RADIX_GTSE for power8 and
older.

Signed-off-by: default avatarGreg Kurz <groug@kaod.org>
Signed-off-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
parent aef19c04

hw/ppc/spapr.c

+10 −5
Original line number Diff line number Diff line
@@ -2512,6 +2512,7 @@ static void spapr_machine_init(MachineState *machine) 
    long load_limit, fw_size;

    char *filename;

    Error *resize_hpt_err = NULL;

    PowerPCCPU *first_ppc_cpu;



    msi_nonbroken = true;
@@ -2592,11 +2593,6 @@ static void spapr_machine_init(MachineState *machine) 
    }



    spapr_ovec_set(spapr->ov5, OV5_FORM1_AFFINITY);

    if (!kvm_enabled() || kvmppc_has_cap_mmu_radix()) {

        /* KVM and TCG always allow GTSE with radix... */

        spapr_ovec_set(spapr->ov5, OV5_MMU_RADIX_GTSE);

    }

    /* ... but not with hash (currently). */



    /* advertise support for dedicated HP event source to guests */

    if (spapr->use_hotplug_event_source) {
@@ -2614,6 +2610,15 @@ static void spapr_machine_init(MachineState *machine) 
    /* init CPUs */

    spapr_init_cpus(spapr);



    first_ppc_cpu = POWERPC_CPU(first_cpu);

    if ((!kvm_enabled() || kvmppc_has_cap_mmu_radix()) &&

        ppc_check_compat(first_ppc_cpu, CPU_POWERPC_LOGICAL_3_00, 0,

                         spapr->max_compat_pvr)) {

        /* KVM and TCG always allow GTSE with radix... */

        spapr_ovec_set(spapr->ov5, OV5_MMU_RADIX_GTSE);

    }

    /* ... but not with hash (currently). */



    if (kvm_enabled()) {

        /* Enable H_LOGICAL_CI_* so SLOF can talk to in-kernel devices */

        kvmppc_enable_logical_ci_hcalls();