Introduce host_cpu_feature_supported() helper, returning
whether a ARM feature is supported by host hardware.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
target/arm/internals.h | 8 ++++++++
target/arm/hvf/hvf.c | 20 ++++++++++++++++++++
target/arm/kvm.c | 22 ++++++++++++++++++++++
3 files changed, 50 insertions(+)
diff --git a/target/arm/internals.h b/target/arm/internals.h
index 1b3d0244fd6..1742dd88443 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -1612,6 +1612,14 @@ bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address,
void arm_log_exception(CPUState *cs);
+/**
+ * host_cpu_feature_supported:
+ * @feature: Feature to test for support
+ *
+ * Returns: whether @feature is supported by hardware accelerator or emulator
+ */
+bool host_cpu_feature_supported(enum arm_features feature);
+
#endif /* !CONFIG_USER_ONLY */
/*
diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c
index 48e86e62945..05fbd8f7fc9 100644
--- a/target/arm/hvf/hvf.c
+++ b/target/arm/hvf/hvf.c
@@ -547,6 +547,26 @@ static struct hvf_sreg_match hvf_sreg_match[] = {
{ HV_SYS_REG_SP_EL1, HVF_SYSREG(4, 1, 3, 4, 0) },
};
+bool host_cpu_feature_supported(enum arm_features feature)
+{
+ if (!hvf_enabled()) {
+ return false;
+ }
+ switch (feature) {
+ case ARM_FEATURE_V8:
+ case ARM_FEATURE_NEON:
+ case ARM_FEATURE_AARCH64:
+ case ARM_FEATURE_PMU:
+ case ARM_FEATURE_GENERIC_TIMER:
+ return true;
+ case ARM_FEATURE_EL2:
+ case ARM_FEATURE_EL3:
+ return false;
+ default:
+ g_assert_not_reached();
+ }
+}
+
int hvf_get_registers(CPUState *cpu)
{
ARMCPU *arm_cpu = ARM_CPU(cpu);
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 66723448554..93da9d67806 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -1771,6 +1771,28 @@ void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp)
}
}
+bool host_cpu_feature_supported(enum arm_features feature)
+{
+ if (!kvm_enabled()) {
+ return false;
+ }
+ switch (feat) {
+ case ARM_FEATURE_V8:
+ case ARM_FEATURE_NEON:
+ case ARM_FEATURE_AARCH64:
+ case ARM_FEATURE_GENERIC_TIMER:
+ return true;
+ case ARM_FEATURE_PMU:
+ return kvm_arm_pmu_supported();
+ case ARM_FEATURE_EL2:
+ return kvm_arm_el2_supported();
+ case ARM_FEATURE_EL3:
+ return false;
+ default:
+ g_assert_not_reached();
+ }
+}
+
bool kvm_arm_aarch32_supported(void)
{
return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL1_32BIT);
--
2.49.0
On 8/13/25 03:31, Philippe Mathieu-Daudé wrote: > Introduce host_cpu_feature_supported() helper, returning > whether a ARM feature is supported by host hardware. > > Signed-off-by: Philippe Mathieu-Daudé<philmd@linaro.org> > --- > target/arm/internals.h | 8 ++++++++ > target/arm/hvf/hvf.c | 20 ++++++++++++++++++++ > target/arm/kvm.c | 22 ++++++++++++++++++++++ > 3 files changed, 50 insertions(+) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
Use the generic host_cpu_feature_supported() helper to
check for the PMU feature support. This will allow to
expand to non-KVM accelerators such HVF.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
target/arm/kvm_arm.h | 13 -------------
target/arm/cpu.c | 6 ++++--
target/arm/kvm-stub.c | 5 -----
target/arm/kvm.c | 9 ++-------
4 files changed, 6 insertions(+), 27 deletions(-)
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index 6a9b6374a6d..364578c50d6 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -177,14 +177,6 @@ void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp);
*/
bool kvm_arm_aarch32_supported(void);
-/**
- * kvm_arm_pmu_supported:
- *
- * Returns: true if KVM can enable the PMU
- * and false otherwise.
- */
-bool kvm_arm_pmu_supported(void);
-
/**
* kvm_arm_sve_supported:
*
@@ -212,11 +204,6 @@ static inline bool kvm_arm_aarch32_supported(void)
return false;
}
-static inline bool kvm_arm_pmu_supported(void)
-{
- return false;
-}
-
static inline bool kvm_arm_sve_supported(void)
{
return false;
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 1dc2a8330d8..ace8e73b532 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -24,6 +24,7 @@
#include "qemu/log.h"
#include "exec/page-vary.h"
#include "target/arm/idau.h"
+#include "qemu/accel.h"
#include "qemu/module.h"
#include "qapi/error.h"
#include "cpu.h"
@@ -1564,8 +1565,9 @@ static void arm_set_pmu(Object *obj, bool value, Error **errp)
ARMCPU *cpu = ARM_CPU(obj);
if (value) {
- if (kvm_enabled() && !kvm_arm_pmu_supported()) {
- error_setg(errp, "'pmu' feature not supported by KVM on this host");
+ if (host_cpu_feature_supported(ARM_FEATURE_PMU)) {
+ error_setg(errp, "'pmu' feature not supported by %s on this host",
+ current_accel_name());
return;
}
set_feature(&cpu->env, ARM_FEATURE_PMU);
diff --git a/target/arm/kvm-stub.c b/target/arm/kvm-stub.c
index c93462c5b9b..3beb336416d 100644
--- a/target/arm/kvm-stub.c
+++ b/target/arm/kvm-stub.c
@@ -32,11 +32,6 @@ bool kvm_arm_aarch32_supported(void)
return false;
}
-bool kvm_arm_pmu_supported(void)
-{
- return false;
-}
-
bool kvm_arm_sve_supported(void)
{
return false;
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 93da9d67806..0aa2680a8e6 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -288,7 +288,7 @@ static bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
1 << KVM_ARM_VCPU_PTRAUTH_GENERIC);
}
- if (kvm_arm_pmu_supported()) {
+ if (host_cpu_feature_supported(ARM_FEATURE_PMU)) {
init.features[0] |= 1 << KVM_ARM_VCPU_PMU_V3;
pmu_supported = true;
features |= 1ULL << ARM_FEATURE_PMU;
@@ -506,11 +506,6 @@ void kvm_arm_add_vcpu_properties(ARMCPU *cpu)
"Set off to disable KVM steal time.");
}
-bool kvm_arm_pmu_supported(void)
-{
- return kvm_check_extension(kvm_state, KVM_CAP_ARM_PMU_V3);
-}
-
int kvm_arm_get_max_vm_ipa_size(MachineState *ms, bool *fixed_ipa)
{
KVMState *s = KVM_STATE(ms->accelerator);
@@ -1783,7 +1778,7 @@ bool host_cpu_feature_supported(enum arm_features feature)
case ARM_FEATURE_GENERIC_TIMER:
return true;
case ARM_FEATURE_PMU:
- return kvm_arm_pmu_supported();
+ return kvm_check_extension(kvm_state, KVM_CAP_ARM_PMU_V3);
case ARM_FEATURE_EL2:
return kvm_arm_el2_supported();
case ARM_FEATURE_EL3:
--
2.49.0
On 8/13/25 03:31, Philippe Mathieu-Daudé wrote: > Use the generic host_cpu_feature_supported() helper to > check for the PMU feature support. This will allow to > expand to non-KVM accelerators such HVF. > > Signed-off-by: Philippe Mathieu-Daudé<philmd@linaro.org> > --- > target/arm/kvm_arm.h | 13 ------------- > target/arm/cpu.c | 6 ++++-- > target/arm/kvm-stub.c | 5 ----- > target/arm/kvm.c | 9 ++------- > 4 files changed, 6 insertions(+), 27 deletions(-) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
Use the generic host_cpu_feature_supported() helper to
check for the EL2 feature support. This will allow to
expand to non-KVM accelerators such HVF.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
target/arm/kvm_arm.h | 11 -----------
hw/arm/virt.c | 8 +-------
target/arm/kvm-stub.c | 5 -----
target/arm/kvm.c | 6 +++---
4 files changed, 4 insertions(+), 26 deletions(-)
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index 364578c50d6..7e5755d76b2 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -191,12 +191,6 @@ bool kvm_arm_sve_supported(void);
*/
bool kvm_arm_mte_supported(void);
-/**
- * kvm_arm_el2_supported:
- *
- * Returns true if KVM can enable EL2 and false otherwise.
- */
-bool kvm_arm_el2_supported(void);
#else
static inline bool kvm_arm_aarch32_supported(void)
@@ -213,11 +207,6 @@ static inline bool kvm_arm_mte_supported(void)
{
return false;
}
-
-static inline bool kvm_arm_el2_supported(void)
-{
- return false;
-}
#endif
/**
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index ef6be3660f5..62350f642ef 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -2267,13 +2267,7 @@ static void machvirt_init(MachineState *machine)
exit(1);
}
- if (vms->virt && kvm_enabled() && !kvm_arm_el2_supported()) {
- error_report("mach-virt: host kernel KVM does not support providing "
- "Virtualization extensions to the guest CPU");
- exit(1);
- }
-
- if (vms->virt && !kvm_enabled() && !tcg_enabled() && !qtest_enabled()) {
+ if (vms->virt && !host_cpu_feature_supported(ARM_FEATURE_EL2)) {
error_report("mach-virt: %s does not support providing "
"Virtualization extensions to the guest CPU",
current_accel_name());
diff --git a/target/arm/kvm-stub.c b/target/arm/kvm-stub.c
index 3beb336416d..35afcc7d6f9 100644
--- a/target/arm/kvm-stub.c
+++ b/target/arm/kvm-stub.c
@@ -42,11 +42,6 @@ bool kvm_arm_mte_supported(void)
return false;
}
-bool kvm_arm_el2_supported(void)
-{
- return false;
-}
-
/*
* These functions should never actually be called without KVM support.
*/
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 0aa2680a8e6..53aebd77bf1 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -274,7 +274,7 @@ static bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
/*
* Ask for EL2 if supported.
*/
- el2_supported = kvm_arm_el2_supported();
+ el2_supported = host_cpu_feature_supported(ARM_FEATURE_EL2);
if (el2_supported) {
init.features[0] |= 1 << KVM_ARM_VCPU_HAS_EL2;
}
@@ -1780,7 +1780,7 @@ bool host_cpu_feature_supported(enum arm_features feature)
case ARM_FEATURE_PMU:
return kvm_check_extension(kvm_state, KVM_CAP_ARM_PMU_V3);
case ARM_FEATURE_EL2:
- return kvm_arm_el2_supported();
+ return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL2);
case ARM_FEATURE_EL3:
return false;
default:
@@ -1918,7 +1918,7 @@ int kvm_arch_init_vcpu(CPUState *cs)
cpu->kvm_init_features[0] |= (1 << KVM_ARM_VCPU_PTRAUTH_ADDRESS |
1 << KVM_ARM_VCPU_PTRAUTH_GENERIC);
}
- if (cpu->has_el2 && kvm_arm_el2_supported()) {
+ if (cpu->has_el2 && host_cpu_feature_supported(ARM_FEATURE_EL2)) {
cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_HAS_EL2;
}
--
2.49.0
On 8/13/25 03:31, Philippe Mathieu-Daudé wrote: > Use the generic host_cpu_feature_supported() helper to > check for the EL2 feature support. This will allow to > expand to non-KVM accelerators such HVF. > > Signed-off-by: Philippe Mathieu-Daudé<philmd@linaro.org> > --- > target/arm/kvm_arm.h | 11 ----------- > hw/arm/virt.c | 8 +------- > target/arm/kvm-stub.c | 5 ----- > target/arm/kvm.c | 6 +++--- > 4 files changed, 4 insertions(+), 26 deletions(-) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
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