From: Greg Kurz Date: Thu, 16 Jul 2020 17:11:21 +0000 (+0200) Subject: spapr: Forbid nested KVM-HV in pre-power9 compat mode X-Git-Tag: v5.2.0-rc0~165^2~31 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=19d55e2031f2473a65ffc11aff5b1059e7c4173b;p=thirdparty%2Fqemu.git spapr: Forbid nested KVM-HV in pre-power9 compat mode Nested KVM HV only works if the kernel is using the radix MMU mode, ie. the CPU is POWER9 and it is not running in some pre-power9 compat mode. Otherwise, the KVM HV module fails to load in the guest with -ENODEV. It might be painful for a user to discover this late that nested cannot work with their setup. Erroring out at machine init instead seems to be the best we can do. Signed-off-by: Greg Kurz Reviewed-by: Laurent Vivier Message-Id: <159491948127.188975.9621435875869177751.stgit@bahia.lan> Signed-off-by: David Gibson --- diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c index 275f5bd0342..10a80a8159f 100644 --- a/hw/ppc/spapr_caps.c +++ b/hw/ppc/spapr_caps.c @@ -382,6 +382,8 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr, uint8_t val, Error **errp) { ERRP_GUARD(); + PowerPCCPU *cpu = POWERPC_CPU(first_cpu); + if (!val) { /* capability disabled by default */ return; @@ -391,6 +393,14 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr, error_setg(errp, "No Nested KVM-HV support in TCG"); error_append_hint(errp, "Try appending -machine cap-nested-hv=off\n"); } else if (kvm_enabled()) { + if (!ppc_check_compat(cpu, CPU_POWERPC_LOGICAL_3_00, 0, + spapr->max_compat_pvr)) { + error_setg(errp, "Nested KVM-HV only supported on POWER9"); + error_append_hint(errp, + "Try appending -machine max-cpu-compat=power9\n"); + return; + } + if (!kvmppc_has_cap_nested_kvm_hv()) { error_setg(errp, "KVM implementation does not support Nested KVM-HV");