| Message ID | 20190503055316.6441-14-sjitindarsingh@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | target/ppc: Implement KVM support under TCG | expand |
On Fri, May 03, 2019 at 03:53:16PM +1000, Suraj Jitindar Singh wrote: > It is now possible to use nested kvm-hv under tcg, thus allow for it to > be enabled. > > Note that nested kvm-hv requires that rc updates to ptes be done by > software, otherwise the page tables get out of sync. So disable hardware > rc updates when nested kvm-hv is enabled. > > Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> > --- > hw/ppc/spapr_caps.c | 22 ++++++++++++++++++---- > target/ppc/cpu.h | 1 + > target/ppc/mmu-radix64.c | 4 ++-- > 3 files changed, 21 insertions(+), 6 deletions(-) > > diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c > index 3278c09b0f..7fe07d83dd 100644 > --- a/hw/ppc/spapr_caps.c > +++ b/hw/ppc/spapr_caps.c > @@ -389,10 +389,7 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr, > return; > } > > - if (tcg_enabled()) { > - error_setg(errp, > - "No Nested KVM-HV support in tcg, try cap-nested-hv=off"); > - } else if (kvm_enabled()) { > + if (kvm_enabled()) { > if (!kvmppc_has_cap_nested_kvm_hv()) { > error_setg(errp, > "KVM implementation does not support Nested KVM-HV, try cap-nested-hv=off"); > @@ -400,6 +397,22 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr, > error_setg(errp, > "Error enabling cap-nested-hv with KVM, try cap-nested-hv=off"); > } > + } /* else { nothing required for tcg } */ > +} > + > +static void cap_nested_kvm_hv_cpu_apply(SpaprMachineState *spapr, > + PowerPCCPU *cpu, > + uint8_t val, Error **errp) > +{ > + CPUPPCState *env = &cpu->env; > + > + if (tcg_enabled() && val) { > + if (env->spr[SPR_PVR] != 0x004E1202) { Hrm. Something other than an explicit PVR check would be nice (or we'll have to keep hacking this when DD2.3 arrives). > + error_setg(errp, "Nested KVM-HV only supported on POWER9 DD2.2, " > + "try cap-nested-hv=off or -cpu power9_v2.2"); > + return; > + } > + env->disable_hw_rc_updates = true; > } > } > > @@ -544,6 +557,7 @@ SpaprCapabilityInfo capability_table[SPAPR_CAP_NUM] = { > .set = spapr_cap_set_bool, > .type = "bool", > .apply = cap_nested_kvm_hv_apply, > + .cpu_apply = cap_nested_kvm_hv_cpu_apply, > }, > [SPAPR_CAP_LARGE_DECREMENTER] = { > .name = "large-decr", > diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h > index 426015c9cd..6502e0de82 100644 > --- a/target/ppc/cpu.h > +++ b/target/ppc/cpu.h > @@ -1237,6 +1237,7 @@ struct CPUPPCState { > target_ulong hv_ptr, regs_ptr; > struct hv_guest_state l2_hv, l1_saved_hv; > struct pt_regs l2_regs, l1_saved_regs; > + bool disable_hw_rc_updates; > }; > > #define SET_FIT_PERIOD(a_, b_, c_, d_) \ > diff --git a/target/ppc/mmu-radix64.c b/target/ppc/mmu-radix64.c > index 2a8147fc38..cc06967dbe 100644 > --- a/target/ppc/mmu-radix64.c > +++ b/target/ppc/mmu-radix64.c > @@ -31,9 +31,9 @@ > static inline bool ppc_radix64_hw_rc_updates(CPUPPCState *env) > { > #ifdef CONFIG_ATOMIC64 > - return true; > + return !env->disable_hw_rc_updates; > #else > - return !qemu_tcg_mttcg_enabled(); > + return !qemu_tcg_mttcg_enabled() && !env->disable_hw_rc_updates; > #endif > } >
diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c index 3278c09b0f..7fe07d83dd 100644 --- a/hw/ppc/spapr_caps.c +++ b/hw/ppc/spapr_caps.c @@ -389,10 +389,7 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr, return; } - if (tcg_enabled()) { - error_setg(errp, - "No Nested KVM-HV support in tcg, try cap-nested-hv=off"); - } else if (kvm_enabled()) { + if (kvm_enabled()) { if (!kvmppc_has_cap_nested_kvm_hv()) { error_setg(errp, "KVM implementation does not support Nested KVM-HV, try cap-nested-hv=off"); @@ -400,6 +397,22 @@ static void cap_nested_kvm_hv_apply(SpaprMachineState *spapr, error_setg(errp, "Error enabling cap-nested-hv with KVM, try cap-nested-hv=off"); } + } /* else { nothing required for tcg } */ +} + +static void cap_nested_kvm_hv_cpu_apply(SpaprMachineState *spapr, + PowerPCCPU *cpu, + uint8_t val, Error **errp) +{ + CPUPPCState *env = &cpu->env; + + if (tcg_enabled() && val) { + if (env->spr[SPR_PVR] != 0x004E1202) { + error_setg(errp, "Nested KVM-HV only supported on POWER9 DD2.2, " + "try cap-nested-hv=off or -cpu power9_v2.2"); + return; + } + env->disable_hw_rc_updates = true; } } @@ -544,6 +557,7 @@ SpaprCapabilityInfo capability_table[SPAPR_CAP_NUM] = { .set = spapr_cap_set_bool, .type = "bool", .apply = cap_nested_kvm_hv_apply, + .cpu_apply = cap_nested_kvm_hv_cpu_apply, }, [SPAPR_CAP_LARGE_DECREMENTER] = { .name = "large-decr", diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h index 426015c9cd..6502e0de82 100644 --- a/target/ppc/cpu.h +++ b/target/ppc/cpu.h @@ -1237,6 +1237,7 @@ struct CPUPPCState { target_ulong hv_ptr, regs_ptr; struct hv_guest_state l2_hv, l1_saved_hv; struct pt_regs l2_regs, l1_saved_regs; + bool disable_hw_rc_updates; }; #define SET_FIT_PERIOD(a_, b_, c_, d_) \ diff --git a/target/ppc/mmu-radix64.c b/target/ppc/mmu-radix64.c index 2a8147fc38..cc06967dbe 100644 --- a/target/ppc/mmu-radix64.c +++ b/target/ppc/mmu-radix64.c @@ -31,9 +31,9 @@ static inline bool ppc_radix64_hw_rc_updates(CPUPPCState *env) { #ifdef CONFIG_ATOMIC64 - return true; + return !env->disable_hw_rc_updates; #else - return !qemu_tcg_mttcg_enabled(); + return !qemu_tcg_mttcg_enabled() && !env->disable_hw_rc_updates; #endif }
It is now possible to use nested kvm-hv under tcg, thus allow for it to be enabled. Note that nested kvm-hv requires that rc updates to ptes be done by software, otherwise the page tables get out of sync. So disable hardware rc updates when nested kvm-hv is enabled. Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> --- hw/ppc/spapr_caps.c | 22 ++++++++++++++++++---- target/ppc/cpu.h | 1 + target/ppc/mmu-radix64.c | 4 ++-- 3 files changed, 21 insertions(+), 6 deletions(-)